Juniper. Mechanical-Biological-Treatment : A Guide for Decision Makers Processes, Policies and Markets TECHNOLOGY & BUSINESS REVIEW

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1 TECHNOLOGY & BUSINESS REVIEW Mechanical-Biological-Treatment : A Guide for Decision Makers Processes, Policies and Markets Annexe D Process Reviews S-Z: SBI SRS Sutco Valorga VKW Wastec Wehrle Werk Juniper

2 Mechanical-Biological-Treatment : A Guide for Decision Makers Processes, Policies & Markets Annexe D Process Reviews Published by: Juniper Consultancy Services Ltd, March 2005, Version 1.0 Principal Authors: Egan Archer, BEng, MSc, PhD, AMIChemE; Adam Baddeley, MSc; Alex Klein, BSc, MSc; Joe Schwager, BA, MICM, AMIMC, MCIWM; Kevin Whiting, BEng, PhD, CEng, FIChemE Acknowledgement This project was funded by UK landfill tax credits provided by Sita Environmental Trust (SET) with additional funding from ASSURRE (The Association for the Sustainable Use and Recovery of Resources in Europe) to each of whom we wish to express our appreciation. We also want to thank Dr Gev Eduljee of Sita, Dr Peter White of ASSURRE, Stuart Reynolds of Norfolk Environmental Waste Services and Andy Saunders of SET, who formed a Technical Advisory Committee. Their insight and many helpful comments were invaluable. We wish to place on record our gratitude to the many process developers, site operators and others who provided information for the preparation of this report. In particular we are grateful to the many individuals who facilitated our visits to reference plants to conduct site appraisals. Many process, product, system and company names cited throughout the text are registered marks. In the interests of legibility, each occurrence is not followed by, or. Nevertheless, we wish to acknowledge the rights of the owners of such marks, and the copyright for figures and pictures used in this report. Copyright Statement Juniper Consultancy Services Ltd All rights reserved. This report may not be copied or given, lent or resold, in part or in whole, to any third party without written permission. Specific additional provisions apply to use of the electronic version of this report. We will also always try and meet reasonable requests from those who wish to quote selectively from the data and analysis contained herein in support of their own technical publications. We ask that you agree the basis of such usage with us in advance and that you always reference the source of the material. Juniper is a registered trademark of Juniper Consultancy Services Ltd. Important Note The inclusion of a supplier or proprietary process in this report does not constitute a recommendation as to its performance or suitability. Equally, non-inclusion does not imply that that process is not suitable for certain applications. We welcome information to assist with the preparation of any future editions of this report. The opinions contained herein are offered to the reader as one viewpoint in the continuing debate about how MBT can contribute to a modern integrated waste management system. They are based upon the information that was available to us at the time of publication and may subsequently change. A wide ranging study of this type may contain inaccuracies and non-current information - for which we apologise in advance. We are always pleased to receive updated information or corrections about any of the processes reviewed for possible inclusion in future editions of the report. This Review has been carried out on a completely independent basis. No payment has been or will be accepted from any process company for inclusion of any information or commentary contained herein. As an analyst active in this field, Juniper also provides confidential consulting services to many companies involved in this sector. We have procedures in place to avoid conflicts of interest, to protect confidential data and to provide 3rd parties with dispassionate, independent advice. Disclaimer This report has been prepared by Juniper with all reasonable skill, care and diligence within the Terms of the contract with the client, incorporating our Terms and Conditions of Business. We disclaim any responsibility of whatsoever nature to third parties to whom this report, or any part thereof, is made known. Any such party interprets or relies on the report at their own risk.

3 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-276 SBI-FRIESLAND SBI-FRIESLAND Summary of the process SBI-Friesland operates an MBT process that utilises anaerobic digestion as the core biological processing step to treat MSW. The process produces biogas, RDF and dry recyclables as the main outputs. The technology is based on an original process design by Grontmij (see separate review), which has subsequently been extensively modified. Type of process being marketed MSW Pre-sorting Wet pretreatment Anaerobic Digestion Fe RDF Recyclables Biogas to electricity & heat Commercial status on MSW feedstock No plant yet built Pilot Plant Demonstrator plant Commercial plant Advantages Disadvantages Key advantages & disadvantages one commercial reference treating MSW operating at relatively large scale technology optimised via operational experience process is a net energy producer via biogas utilisation no current visibility as an MBT supplier and not well known outside of The Netherlands commercial plants not yet supplied to others as with many other Continental processes, the digestate output would not currently meet UK ABPR requirements SBI is more of an operating company than a process engineering firm Contact details Afvalsturing Friesland, Hidalgoweg 5, Postbus 1622, 8901 BX Leeuwarden, The Netherlands. Tel: Fax: Key contact H. Smink h.smink@afnv.nl

4 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-277 SBI-FRIESLAND Overview D SBI Friesland (Scheidings- en Bewerkings Installatie) is the name of the 220,000 Tpa MBT plant being operated at Heerenveen in the province of Friesland. The plant is owned by Afvalsturing Friesland (referred to as SBI in this review) and was built in 2002 in conjunction with the engineering consulting firm Grontmij who has a 25% stake in the facility. Originally, the process integrated the Waasa digestion system from Citec with the same pre-sorting and wet pre-treatment systems used at the Groningen MBT plant (see Grontmij process review). The Friesland plant was built by Synmet (pre-sorting section) and GTI (a large Dutch technical and building services company), who we understand is the licensee of the Waasa digestion technology in The Netherlands. D The plant operators advised us that subsequently they have made extensive modifications to the facility, including removing the Citec technology and re-designing the Vagron process. We understand that SBI is now promoting the re-designed concept as their system for third party MBT projects. D Afvalsturing Friesland is part of OMRIN a regional waste management company that operates in the north of The Netherlands and manages the municipal waste arisings of its 31 shareholding municipalities including the province of Friesland. The company has over 500 employees and reported an annual turnover of c. 100M. Figure D204: SBI Friesland plant in Heerenveen Digesters Wet pre-treatment building Pre-sorting building Power plant Transporting <50mm Waste reception Source: SBI

5 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-278 SBI-FRIESLAND D Juniper visited the SBI plant in November During our site visit we had extensive discussions with a representative of Afvalsturing Friesland, who explained via a presentation and a tour of the plant, the problems they had experienced with the original process and the extensive design changes they had made. D The plant was fully operational when we visited. We observed the housekeeping to be below average; but noted that the plant had recently undergone process changes and was still undergoing some structural modifications (mainly to the wet pre-treatment and digestion processes). This meant that temporary lines, conveyors and storage areas were being used to bypass redundant equipment to facilitate the 3-shift continuous operation of the plant. It was explained that all of the plant modifications were made whilst the plant continued to receive waste at full capacity. D Though we detected some odorous emissions from the process this could partly be attributed to the temporary arrangements (which included some outside storage) in place for processing the wet organic fraction before it is sent for digestion. Status of the Plant at Heerenveen D The SBI process has so far only operated at Heerenveen. There are no other projects currently being proposed with this process. Figure D205: Work on digesters at Heerenveen Source: SBI

6 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-279 SBI-FRIESLAND D The Heerenveen plant began operation in May The plant was started in phases, with the pre-sorting process coming on-stream first. This was followed in August of the same year by the wet pre-treatment and the digestion processes. The process was then optimised over the course of 12 months, which identified a number of problems and bottlenecks. D In late 2003, two of the three digesters were taken out of service because of extensive problems with floating layers (light materials that included corks, plastic tubes and polystyrene that floated to the top of the digester). The floating layer can solidify to some degree and affect the stirring of the digester s contents and thus affect its operational performance. Figure D206: Changes to the wet pre-treatment process at Heerenveen Before Modifications Fraction < 55mm pre-sorting plant Inert Separator Coarse inerts Drum Sieve Coarse organics Shredder To digestion plant Process water Hydrocyclone Disc Strainer Thickener Flotation Tank Sand Fine organics Wood/Coal Separator Poly-electrolyte Coarse particles Sand After Modifications Fraction < 55mm Inert Separator Rake fraction to RDF Coarse Inerts Drum Sieve Coarse organics Shredder To digestion plant Process water Hydrocyclone Fine organics Sludge Centrifuge Sand KEY Further Upgrading Residue Stream Source: Juniper interpretation of SBI s information

7 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-280 SBI-FRIESLAND D The internal pre-digestion compartment in the original Citec design was removed and the fixed roof changed to a flanged access for relatively quick removal, if necessary. Changes were made to purge the digesters from both top and bottom (originally this was only carried out at the bottom of the digester) to reduce the build-up of floating nondigestible layers of materials and sediment respectively. D Significant changes have also been made to the wet pre-treatment part of the process (see Figure D206). SBI informed us that the changes were necessary as a result of the poor separation of light materials that contributed to the floating layer build-up in the digesters and the unreliability of the wet pre-treatment process. This re-designed process was fully operational when we visited the plant. The Process operated at Heerenveen D The front-end mechanical pre-sorting part of the process is the same as that being operated at Groningen (refer to the Grontmij process review) except that only ferrous metals are recovered in the pre-sorting plant. The operator told us that they had removed the eddy current separators because of their poor availability but planned to replace them. In the meantime some ferrous metals and non-ferrous metals, such as aluminium, will be present in the RDF stream and could be a potential issue for RDF offtake clients. D The RDF is transported off-site in press-containers or walking floor trailers, while the paper/plastic fraction (see Figure D207) is wrapped as plastic bales before being stored/transported off-site. D The materials <55mm from the pre-sorting plant are sent to an inert separator; this separates the dense and less dense materials in an upflow stream of water. In this stage coarse inerts are also removed from the process. In addition, and as part of the process modification, light floating materials are removed by a rake and added to the RDF stream. D The finer materials caught up in the water stream are sent to a washing drum screen, which separates the sand and fine organics from the coarse organics. The coarse organics are shredded and sent directly to the digestion plant. D The sand and fine organics are passed through a hydrocyclone, which separates them. The sand is sent to storage for re-use or landfill, while the fine organics are sent via a sludge centrifuge, which removes water, to the digestion plant. The liquid stream from the centrifuge ( centrate ) is then added to the process water going to the drum sieve (see Figure D207). D In the digestion plant, the organics are mixed with hot water and raised to an operating temperature of about 57 0 C before entering the digester.

8 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-281 SBI-FRIESLAND Figure D207: MBT process as operated at the Heerenveen plant MSW Air Separator Magnetic Separator Trommel 1 >200 mm Plastics & paper Fe metals RDF <200 mm >55 mm Air Separator Trommel 2 <55mm Magnetic Separator Fe metals Inert Separator Rake fraction Light plastics to RDF Coarse inerts Drum Sieve Coarse materials (>4mm) Shredder Process water Hydrocyclone Fine organics Sludge Centrifuge To digestion plant Sand Hot water from the CHP plant Mixer Wet organic fraction Anaerobic Digester Cleaned biogas Process water to drum sieve Digestate Gas Engine To wastewater treatment Belt press Heat & Power Digestate to immobilisation plant Exhaust gases KEY Recyclables Further Upgrading Emissions Residue Stream Energy Source: Juniper interpretation of SBI s information

9 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-282 SBI-FRIESLAND D The digesters each have a volume of 3000m 3 and of this, 200m 3 is purged daily and the same amount of fresh material is transferred from the mixing reactors to the digester. At Heerenveen the purge system has been modified to remove 70% at the top of the digester and 30% at the bottom. D The digestate is dewatered using a belt press before it is sent to the immobilisation plant. The immobilisation process is described in the section on Process Outputs. Water from the belt press is recycled as process water to the drum sieve and the remainder sent to wastewater treatment. Process Performance D The mass balance for the process operated at Heerenveen is shown in Figure D208. Based on this balance, the waste diversion potential has been calculated and summarised in Figure D209 (along with the relevant assumptions that have been made in the calculations). Figure D208: Mass balance for the process operated at Heerenveen Waste Feed (100 wt%) Metals ( 3%) Coarse Inerts (6 %) Sand (5 %) Rake fraction to RDF (3 %) Pre-treatment Water + Steam (c. 9%) Oversized Fractions (56%) Fine Fraction (41%) Wet Pre-treatment to AD plant (36%) Refining of Trommel Oversize fractions Process water Anaerobic Digestion Plant RDF (40%) Paper + Plastics (16 %) Excess Water (14%) Biogas (6 %) Digestate (16%) Source: Juniper s analysis of SBI data

10 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-283 SBI-FRIESLAND Figure D209: Diversion potential (by mass) based on the process operated at Heerenveen Diversion Potential Minimum, % Maximum, % Basis of Estimation Percentage of the input waste diverted from landfill Min: Inert streams and digestate landfilled. RDF and light plastics & paper also landfilled. Max: All inerts (incl. sand) landfilled. Note: This is total mass diversion not BMW diversion under UK diversion targets. No data is available on the biodegradability of the process streams. Source: Juniper analysis D The diversion data in Figure D209 indicates that a significant amount of materials is currently being diverted from landfill by processing waste in the Heerenveen plant. As with the process being operated at Groningen, a relatively high diversion rate (90%) is obtained if the RDF is used as fuel and if the digestate can be used as landfill final cover. The higher diversion rate calculated at Heerenveen is due to the rake fraction that is recovered and combined with the RDF stream that is currently sent for incineration. D No data on the biodegradability of the output streams was made available for this review (c.f. Groningen) and hence we could not determine the BMW performance of the process being operated at Heerenveen. Energy Balance D No energy balance data was provided for this review. Availability and Reliability D The performance of the process at Heerenveen is shown in Figure D210. Based on the capacity of the plant, the design throughput of the pre-sorting section is 55,000 Tonnes per quarter (220,000 Tpa). The design throughput of the wet pre-treatment part of the process, based on Figure D208, is 22,550 Tonnes per quarter (90,200 Tpa). D The data summarised in Figure D210 shows that the plant only reached its design capacity in the 2 nd quarter of 2004, after the extensive process modifications. D The design modifications at Heerenveen have only been fully operational in the last 3-6 months and therefore the process has not yet operated for a sufficient period of time to be classified as fully proven on a commercial basis.

11 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-284 SBI-FRIESLAND Figure D210: Actual plant throughput at Heerenveen Tonnes per quarter (1st Quarter) 2003 (2nd Quarter) 2003 (3rd Quarter) 2003 (4th Quarter) 2004 (1st Quarter) 2004 (2nd Quarter) 2004 (3rd Quarter) Source: SBI Process Outputs D Figure D211 lists the quantities of outputs that can be obtained from the process at Heerenveen. D Biogas: The biogas yield is reported to be about 110 Nm 3 /Tonne of input to the digester (i.e. c. 40 Nm 3 /Tonne input to the plant). No data was made available to allow an assessment of whether the modifications to the plant changed the biogas yield. D The methane composition is between 55 and 60% (by volume) and the gas is used to produce electricity via gas engines. D The gas engines are cooled with water and the hot water produced is used in the predigestion mixer. D At Heerenveen, the gas engines utilise both landfill gas from the site adjacent to the plant, and biogas. The biogas is cleaned using sludges (c. 60 Tonnes per week) from drinking water preparation. The sludge contains iron hydroxide, which removes hydrogen sulphide (H 2 S) by precipitation. The residues from the biogas cleaning stage are sent to the digesters. Following H 2 S abatement, the biogas is cooled to remove water and then pressurised for use in the gas engines. No information was provided about the

12 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-285 SBI-FRIESLAND composition of the cleaned biogas going to the gas engines or the composition of the exhaust emissions. D The landfill gas is separately treated in scrubbers before being mixed with the cleaned biogas. D We were informed that the gas engines on the Heerenveen site are owned by a power generation company, which pays green tariff rates for the off-take of biogas from the Heerenveen plant rather than the more usual power off-take contract. Figure D211: Outputs from the process at Heerenveen Products Tpa Application Biogas 12,110 utilised in gas engines in CHP configuration Ferrous metals 6,900 recycled Coarse inerts 12,110 may be recycled but may have to be landfilled Fine inerts (sand) 10,092 may be recycled but may have to be landfilled RDF 80,734 sent for incineration and as a secondary fuel Rake fraction 6,055 sent for incineration and as a secondary fuel Paper & light plastics 32,294 used as a co-fuel in cement kilns and CHP plants Digestate 32,294 sent to landfill after immobilisation to be used as landfill permanent cover Wastewater 28,257 treated and discharged Source: Juniper calculation from data supplied by SBI D RDF: We were informed that the RDF is currently being disposed of in an incineration plant in The Netherlands and being sold as a secondary fuel in Germany. SBI informed us that the contract for incinerating the RDF will expire on the 1 st January 2005 at which time all of the RDF output from the Heerenveen plant will be sent to Germany. D No further details were provided about the specific use of the RDF in Germany, but we gathered from our discussions with SBI that the RDF is mixed with other secondary fuels before use. No data on the composition of this stream was provided for this review. D We were told that the recovered paper and plastic fraction is also being sent to Germany as a fuel, but we were unable to obtain details of the off-take contracts that might be in place for this output. D Because of the lack of composition data for the RDF and the paper/plastic fraction from the Heerenveen plant we are unable to assess the quality of this material against market requirements.

13 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-286 SBI-FRIESLAND D Digestate: The digestate output from Heerenveen is sent to an on-site immobilisation plant, where it is mixed with water glass 1, bottom ash and sludges before being used as landfill permanent cover. D In the UK, this method of utilisation would probably count as recycling, provided that the material satisfies the UK APBR criteria. At present, the digestate output from Heerenveen would not satisfy UK ABPR because, among other factors, the processing conditions do not meet the specified criteria in the regulations. In lengthy discussions with the plant operator, it is apparent that some changes to provide extra heat to the pre-digestion mixing reactor would have to be made in order to achieve UK ABPR processing requirements. Such changes could have knock-on effects on the operational performance of the digester and may require complex controls to ensure that the active micro-organisms in the digester are not destroyed. Environmental Impact D D Gas cleaning: All waste gases from the process and the plant are captured and piped to a biofilter. The company claims that this minimises any risk of bio-aerosol, dust and odorous emissions. Wastewater: Much of the wastewater generated within the process is re-used in the wet pre-treatment stage. However, some wastewater is continuously purged because of the build-up of chlorides and nitrates, which is said to affect the performance of the digester when they are above certain limits. The purged wastewater is treated and some of it is re-used in those parts of the process that require clean water, such as the sieve screen. No data was made available of the quality of the water that is sent to sewer after treatment. Footprint & Visual Impact D The tallest process elements are the digesters, which are 25m high. The plant is located in an industrial area and as a result its visual impact was not an issue. D The land-take appeared to be significant, but the facility, located adjacent to the operators own landfill site, also included office buildings, on-site wastewater treatment and storage areas for baled RDF. We were not provided with quantitative land-take data for the Heerenveen facility. 1 water glass is the common name for sodium metasilicate (Na 2 SiO 3 ), a colourless, jelly-like substance that dissolves readily in water used for preserving eggs and fireproofing porous materials, such as cloth, paper and wood. It is also used in the manufacture of soap and silica gel.

14 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-287 SBI-FRIESLAND Figure D212: Two of the three anaerobic digesters at Heerenveen Source: Photograph taken by Juniper during site visit Costs D A breakdown of costs provided by SBI is summarised in Figure D213. Figure D213: Breakdown of investment costs for Heerenveen Products (million) Separation Unit (pre-sorting process) 9 Washing unit (wet pre-treatment process) 6.2 Digestion unit 19.8 Miscellaneous (planning, design, infrastructure) 3 Total costs 38 Source: SBI D The company has also published (see Figure D214) the cost price for managing outputs from the process.

15 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-288 SBI-FRIESLAND Figure D214: Current and projected costs (/Tonne) for managing outputs from Heerenveen Source: SBI (Taken from paper Sustainable waste management by an integrated solid waste treatment plant in Friesland, the Netherlands, presented at ISWA, Rome 2004) Outstanding Questions No compositional data for the RDF output and the plastic/paper fraction was provided for this review; We are unable to verify where these materials are being used in Germany and have not reviewed any contracts that might be in place; No energy balance data was provided; Data on biogas yield over a reasonable period of time was not provided; The quality of the wastewater discharged to sewer after treatment was not provided. RDF specifications required by customers not provided. Summary D OMRIN is owned by 31 municipalities, which are shareholders in the company. While this may help SBI pursue opportunities for their waste treatment process in the Netherlands, the company has no visibility as an MBT supplier outside of The Netherlands. Until we visited the company in November 2004, we were unaware that

16 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-289 SBI-FRIESLAND they were promoting an MBT process that they have developed from the original design supplied by Grontmij. D While the modifications to the process appear to have had a major effect on performance, the re-designed process has not yet operated for a sufficient amount of time to be regarded as commercially proven. D It is unclear whether SBI themselves will actively market the technology outside The Netherlands and whether they would promote a similar concept as that being operated at Heerenveen, with which they have relevant operational experience. While we had some concerns about who owns the Intellectual Property Rights (IPR) due to the involvement of a multiplicity of process and technology developers, we were informed by SBI that there is no external IPR in relation to the SBI installation. D SBI has an engineering consultancy division that wishes to develop opportunities to build on their experience gained in adapting the process at Heerenveen. They are interested in advising potential customers and also in developing tailored solutions for individual projects. But they are also exploring the possibility of offering turnkey projects. D We are not in a position to comment on the extent to which SBI, as a municipally-owned waste management company, has the capability to support commercialisation of their MBT configuration on behalf of third party customers; especially for projects in other countries, like the UK. Whilst they clearly have the expertise to optimise and develop the original process to better meet their own on-site requirements, SBI would need to satisfy potential users of the technology that they had sufficient resources, either internally or through appropriate partnerships, to be chosen as the preferred contractor in a competitive tender. This review was prepared in November 2004 based on information received during our site visit to the Heerenveen plant in the same month. The review was finalised in December 2004, following further clarification discussions with SBI.

17 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-290 SRS SRS Summary of the process SRS markets a range of waste treatment technologies, including an in-vessel composting technology developed by the Canadian company Wright Environmental. This composting technology has been incorporated in an MBT configuration at two plants in Scotland, where the main output is a bio-treated solid which is being used for landfill restoration and final cover for closed landfills. Type of process being marketed MSW Presorting In-Vessel Composting Bio-treated solids for usage on landfill Fe-metals Commercial status on MSW feedstock No plant yet built Pilot Plant Demonstrator plant Commercial plants Advantages Disadvantages Key advantages & disadvantages simple low cost approach operating plants in the UK relatively low mass diversion because outputs are sent to landfill process concept used in Scotland is different from that developed in North America does not maximise resource recovery Contact details Sustainable Recycling Solutions Ireland Ltd., c/o Turmec Engineering Ltd, Rathcairn, Athboy, Co Meath, Ireland Tel: Fax: Key contact Phil May-Brown phil.maybrown@ntlworld.com

18 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-291 SRS Overview D Sustainable Recycling Solutions Ireland (SRS) and its sister company Sweeney Environmental are agents for a range of waste treatment technologies including an invessel composting process developed by the Canadian company Wright Environmental. We were informed that SRS is licensed to market and build the Wright Environmental technology outside of the Americas. D Wright Environmental was founded in 1992, and is reported to have supplied more than 55 in-vessel composting plants in the United States, Canada, and the United Kingdom. The company does not promote an MBT process but their composting technology is the core biological treatment step being used at two plants in Scotland, configured as MBT, to treat unsegregated MSW. The main output from these plants is currently being used for landfill restoration. Status of Technology D The two existing reference plants have been operated by Aberdeenshire County Council since The plants are located in Inverboyndie and Mintlaw and are designed to process 26,000 Tpa and 32,000 Tpa of mixed MSW respectively. We understand from the Council that both of these plants have experienced significant downtime over the last few years. We were informed separately by SRS and the Council that the downtime was due to optimisation trials to reduce the quantity of biodegradables being rejected in the pre-treatment stage to landfill and the discussions that were being held with SEPA with regards to the utilisation of the bio-treated materials. Figure D215: Waste pre-treatment plant at Inverboyndie Source: Wright Environmental website

19 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-292 SRS Description of the MBT processes in Scotland Waste feeding D The incoming waste is visually inspected to remove oversized and unsuitable materials. The waste is then sent to a modified pulveriser, which breaks opens the waste bags and reduces the size of the particles. D The materials from this stage are then passed through an electromagnetic separator to recover ferrous metals and then split into two size fractions, >30mm and <30mm by a trommel. The >30mm fraction goes directly to landfill without any further processing. Figure D216: Schematic of the Wright Environmental technology as configured in Scotland Mixed MSW bulky wastes Pulveriser Fe-Metals Magnetic Separator Sent to landfill Trommel >30mm <30mm Waste gases to biofilter Mixing In-Vessel Composting Wastewater to sewer water structure materials air water Compost for landfill cover KEY Recyclables Further upgrading Effluent Stream Residue Stream Source: Juniper analysis of SRS information

20 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-293 SRS Composting D The screen undersized fraction (materials <30mm) is conveyed to a mixing stage where it is homogenised and placed on trays, which are mechanically moved through the forced aerated composting unit (also referred to as composting tunnels). Each composting unit has 30 trays and each tray can hold a capacity of five Tonnes of separated waste (i.e. 150 Tonnes per unit). The Wright Environmental in-vessel composting process usually takes about 14 days to complete the biological activity depending on the size cut at the trommel. During this time the waste is usually held at about 60 0 C for the first three days; after seven days it is turned by mechanical spinners, which move the partially digested material into the second zone of the two-zone composting system where the waste is composted for a further seven days at a temperature of 30 0 C. D We understand that, at the time of writing, only the first zone of the composting system is being used at the Scottish plants and as a result the waste is currently being composted for only seven days. D Halving the treatment time increases the throughput of the plant but at the same time it reduces the levels of putrescible degradation and pathogen kill. If this happens, the outputs used as landfill cover might contain significant quantities of putrescibles (potentially causing concerns about odour and other environmental impacts) and possibly high levels of pathogenic bacteria. We assume that an indication of the quality of the output stream produced at the shorter composting time has been reviewed by SEPA, but we have not been provided with any data for review. D Usually after the material has been exposed to the 14 day composting cycle, a further four weeks of maturation is required to produce a bio-stabilised compost. This is the method of operation used in Wright Environmental s North American plants. We were informed that no maturation is performed at the Inverboyndie site, and the waste is sent directly to be mixed with sand for use for landfill restoration. D At the Mintlaw site the material is matured in windrows for 14 days following the seven day composting cycle and is then mixed with sand for use as landfill cover. We were informed by SRS that the Mintlaw site has sufficient space for on-site maturation, while the site at Inverboyndie does not. D Leachate from the composting process is collected and recirculated as process water. It is claimed that this recirculation is feasible for up to about two months, after which time the wastewater is discharged to sewer. This recirculation of the water will lead to a gradual build up of contamination in the leachate. Therefore, regular purging of this stream to sewer will be required. Re-using process water will also need to comply with UK ABPR requirements to avoid cross-contamination of the bio-treated output as it is being used on land. The waste gases generated during composting are passed through a biofilter before passing to the atmosphere.

21 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-294 SRS Future plans D We were informed that the operating company of the Scottish plants is currently installing a containerised Alpheco composting system, which would be used to treat residues from both MBT plants. The Alpheco system will be designed to further compost the residues for a total of seven days and for two of these days the residues will be treated at 60 0 C, in order to satisfy some elements of the ABPR criteria for using the final residues on land. Process Performance D Typical inputs and outputs for the processes operated in Scotland are shown in Figure D217. Based on this balance, the waste diversion potential has been calculated and summarised in Figure D218 Figure D217: Typical inputs and outputs for the MBT plants operated in Scotland Waste Feed (100%) Bulky waste (1-2%) Waste gases (incl. water vapour) (Not specified) Magnetic Separator Fe-metals (1-3%) Shredder & Pulveriser In-Vessel Composting Fraction (<30mm) Trommel Oversized fraction (>30mm) to landfill (55-60%) Landfill restoration (12%) Waste- water (Not specified) Source: Juniper analysis of data from Aberdeenshire County Council

22 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-295 SRS Figure D218: Diversion potential of the MBT plants operated in Scotland Diversion Potential Percentage (wt) Percentage of the input waste diverted from landfill < 40 Note: This is not BMW diversion under UK diversion targets but total mass diversion Source: Juniper analysis D This is a relatively low mass diversion rate and we would expect that the BMW diversion rate would also be low. Environmental Impact D Gas cleaning: The composting tunnels are maintained under a slight negative pressure and the collected composting off-gases are piped to a bio-filter before emission to atmosphere. No analysis of the final emissions was made available and therefore we could not assess how well odorous contaminants and particulates were abated. D D Bio-treated solids: As we have pointed out above, the composting time used is 50% of the normal time (as implemented in North America) used for this composting technology. This will have an effect on the composition of the solids being used for landfill restoration and thus the biodegradability and heavy metal concentration of that material. The heavy metal composition of the bio-treated materials produced at Inverboyndie is summarised in Figure D219. The data is compared with PAS100 requirements and the heavy metal composition of MSW. Figure D219: Results of tests on the bio-treated materials produced at Inverboyndie Sample Source Cu Pb Hg Ni Zn Cd Cr Inverboyndie (mean), mg/kg PAS100, mg/kg dry matter < Unsorted MSW, mg/kg Source: Taken from data supplied by SRS D Although these results, provided by SRS, indicate that the bio-treated material could have lower heavy metal content than the PAS100 requirements, the levels of other pertinent physical (glass etc.), chemical (phytotoxins) and biological (pathogens) contaminants were not reported. Furthermore, the basis of the tests on the Inverboyndie samples is not known. We therefore conclude that the information is insufficient to determine whether the compost would meet PAS100 criteria.

23 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-296 SRS Process Availability and Flexibility D We have not been able to obtain detailed information about the availability of the two Scottish plants. Process Scale D SRS markets its technology as a modular system. The technology has been implemented using composting modules from 0.25 Tpd to 30 Tpd. Typical modules appear to have capacities of Tpd. The Inverboyndie plant utilises 2 25 Tpd modules and the Mintlaw plant has 3 25 Tpd modules. If implemented at this modular scale for future plants, we would not expect any significant scale-up risks. Footprint D The reported footprint of the composting plant with mechanical pre-treatment is 0.13m 2 /Tpa. It is also reported that a further 0.15 m 2 /Tpa would be required if maturation of the residues were to be carried out on-site. Costs D The capital costs of the Inverboyndie plant were reported to be about 2.5M (c. 3.75M). The treatment costs are reported to be about 35-40/Tonne (c /Tonne). Outstanding Questions D We have been unable to review data on the availability of the Scottish reference plants. D The mass balance data was incomplete. No data on the energy requirements of the process was provided for this review. D Although some data was provided on the heavy metal content of the bio-treated materials, information on other relevant contaminants was not made available for this review. D We are unclear about the way in which the wastewater from the process is treated. No data on wastewater quality was provided for this review.

24 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-297 SRS Summary D Wright Environmental supplies a composting process that has been proven over a number of years on various organic waste fractions. However, the plants in Scotland are the only facilities in which the Wright Environmental composting process has been used for treating unsegregated MSW. At these plants the composting process is operated differently from the way in which it has been implemented at other successful reference plants in North America. D The process rejects a significant quantity of the incoming waste, which is sent to landfill, and as a result the diversion is relatively low. Even so, it may be sufficient to reach relevant local BMW diversion targets, which could make this relatively simple and potentially low cost approach an attractive option for some Local Authorities. However, some of the potential disadvantages associated with this approach are: low recycling rates; poor overall recovery; and, a limited scale of implementation because of the finite outlet for products. This review was prepared in September 2004 based on information received in February and April 2004 and from discussions with SRS and Aberdeenshire Council. The review was finalised in October 2004, following further clarification discussions with SRS.

25 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-298 SUTCO SUTCO Summary of the process Sutco markets an MBT process for treating MSW based on a waste composting system, which is called Biofix. The main outputs from the process are an RDF and a bio-stabilised output, which is landfilled. Type of process being marketed Residual MSW Mechanical pretreatment Composting Refining Stage Bio-stabilised output Fe-metals RDF RDF Commercial status on MSW feedstock No plant yet built Pilot Plant Demonstrator plant Commercial plant Advantages Disadvantages Key advantages & disadvantages process demonstrated on MSW significant experience with the design of the front-end mechanical pre-treatment equipment, which should minimise processing risks process is a net energy user co-firing opportunities for the RDF may be difficult to secure in the UK Contact details Sutco RecyclingTechnik Gmbh & Co. KG, Britanniahütte 14, D Bergisch Gladbach, Germany. Tel: Fax: Key contact Udo Voß Managing Director udo.voss@sutco.de

26 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-299 SUTCO Overview D Sutco Maschinenbau Gmbh markets an MBT process based on composting. The composting process is called Biofix and it takes place in open bays, which are housed in an enclosed building. D Sutco was founded in In 2003, the company along with its Polish subsidiaries Sutco Polska (manufacturing and regional marketing facility) and Sutco Biuro Inzynierskie (engineering office), were acquired by the German waste technology supplier Ludden & Mennekes Entsorgungs-Systeme GmbH after Sutco was sold by RWE Umwelt AG earlier in the same year. D The company is well known for designing and building individual mechanical equipment and process systems for different waste sorting, separation and refining operations including MRFs, DSD 1 facilities, plants producing RDF and sorting of MSW before thermal treatment. In addition, Sutco has supplied pre- and post-treatment equipment to a number of MBT plants supplied by others. Figure D220: Sutco s Erbenschwang plant Stack for gases from biofilter Composting plant Enclosed bio-filter Source: Sutco 1 DSD = Duales System Deutschland, the German producer responsibility recycling infrastructure

27 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-300 SUTCO D We visited Sutco s Erbenschwang reference plant in October 2004, which treats all of the residual MSW and biowaste arisings from Weilheim-Schongau county in Germany. During our visit, we had detailed discussions with the Managing Director of Sutco and with the deputy managing director of EVA GmbH (Erbenschwanger Verwertungs-und Abfallentsorgungs), the operators of the plant. As a result of these discussions EVA supplied us with detailed data for the plant operation. While we had understood that this plant was operational, at the time of our visit the process was being rebuilt to significantly increase the residual waste capacity. Additions were also being made to meet the limits in the German 30 th BImSchV regulations. The enlarged plant is expected to be in operation in January D The Erbenschwang plant also processed about 16,000 Tpa biowaste in a separate line but this was also not operational when we visited the site. All the process buildings were low profile structures (see Figure D220) and are adjacent to the operator s own landfill site. Status of Technology D Sutco provided a list of five MBT references, which are shown in Figure D221. However, only the plant at Erbenschwang in Germany is a full MBT supply utilising Sutco s Biofix process. Figure D221: Sutco s MBT references treating residual MSW Location Plant Capacity, Tpa Current Status Scope of Supply Startup Düren-Horm, North Rhine- Westphalia, Germany 180,000 Mechanical pretreatment 1995 Erbenschwang, Bavaria, Germany 22,000 Biofix process 1997 (plant being expanded) Bassum, Lower Saxony, Germany 60,000 Mechanical pretreatment 1997 Singhofen, Rhineland-Palatinate, Germany Neuss, North Rhine-Westphalia, Germany 45 T/h Mechanical pretreatment 206,000 Mechanical separation plant Piemont, Italy 18,000 Biofix process Being built The colour coding system in denotes plants currently operating ( ), plants that are under construction, under commissioning or in planning ( ) and plants that have stopped or are no longer being built ( ). Source: Sutco D The Erbenschwang plant operated from 1997 to 2004 with the process shown in Figure D222. The main output was a bio-stabilised output (produced after 30 days composting)

28 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-301 SUTCO for landfilling. The operators told us that their target respiration activity for the biostabilised output was below 20 mg O 2 /g ds 1. D The process is currently being upgraded to treat more waste and to meet the new German regulations on bio-stability of residues going to landfill as discussed below. Figure D222: The process that operated from at Erbenschwang, Germany Residual MSW Picking Line Bulky Wastes Crusher > 80mm Sieve Drum Metals Rejects < 80mm Magnetic Separator Heavy fraction Air Separator Fe-metals Air & Water > 140mm RDF to baler Homogenising Trommel Screen Composting Bays Off-gases to biofilter Stabilised materials to landfill KEY Recyclables Further Upgrading Emissions Residue Stream Source: Juniper s representation of Sutco s information The Process D The new process under construction at Erbenschwang receives waste in a flat bunker. The waste is transported by wheel loader to a crusher, which reduces the size of the incoming materials to about 300 mm. The crushed waste is conveyed to a sieved drum that separates it into two fractions of particle sizes: >80 mm and <80 mm. The >80 mm fraction is passed through an electromagnetic separator which recovers ferrous metals. 1 ds = dry solids

29 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-302 SUTCO Non-ferrous metals are not separated from the waste stream at this plant because it is deemed to be uneconomic for this process capacity because of the high degree of household separation conducted in Germany. The remaining materials after metals recovery are baled and sent for use off-site as an RDF in an incineration plant. Ferrous metals are also recovered from the <80mm fraction before it passes to a homogenising mixing drum to which water is added. The homogenised materials are sent for composting. Figure D223:The new process at Erbenschwang, Germany Residual MSW Magnetic Separator Baling Press Crusher >80mm Fe-metals RDF fraction Sieve Drum <80mm Water Air & Water Off-gases to RTO Off-gases to biofilter Magnetic Separator Rotating Drum Mixer Intensive Composting Bays Maturation Bays Fe-metals Air Separator 25-50mm Star Screen <25mm >50mm Fluff Inerts to landfill Stabilised materials to landfill RDF fraction KEY Recyclables Further Upgrading Emissions Residue Stream Source: Juniper representation of EVA information D This description corresponds to Figure D223. The composting process is carried out in open-top bays which are housed in an enclosed building. They are aerated via a combination of pressure aeration, for 4-5 hours per day, and a suction system (suction aeration is the predominant method of aeration used for the remainder of the day). The waste is loaded into these bays by an automatic loading and turning machine and is composted for 30 to 40 days during which time the waste is turned about seven times within each bay by the mobile Biofix windrow turning device. During turning, fresh or process water can be added to the waste. After the intensive composting step, the materials are transferred to another set of bays, where they undergo maturation for a further days. The bio-stabilised output for the maturation bays is separated by

30 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-303 SUTCO star screen 1 into three fractions. The <25 mm fraction is sent to landfill without any further processing. The mm fraction passes to an air density separator, which separates the light organics ( fluff ) from the mostly inert materials. The fluff and >50 mm fraction is marketed as an RDF. The inerts are sent to landfill. Process Performance D Typical inputs and outputs for Sutco s Biofix process, as previously operated at Erbenschwang, are shown in Figure D224. From these numbers, the waste diversion potential has been calculated and summarised in Figure D225 along with the relevant assumptions that have been made in the calculations. Figure D224: Typical inputs and outputs for Sutco s Biofix process Residual MSW (100%) Mechanical Pre-treatment Composting Off-gases (incl. water vapour) (15.1 %) Fe-metals (2.5%) RDF fraction (>80mm) (40 %) Mechanical postseparation Fluff (0.7 %) Bio-stabilised output & inerts to landfill (32.5 %) RDF fraction (>50mm) (9.2 %) KEY Recyclables Further Upgrading Emissions Residue Stream Source: Juniper analysis of Sutco data Figure D225: Landfill diversion potential (by mass) of Sutco s Biofix process Diversion Potential Minimum, % Maximum, % Basis of Estimation Percentage of the input waste diverted from landfill Min: RDF, inerts and bio-stabilised output to landfill Max: RDF is used for energy recovery, biostabilised output and inerts sent to landfill Note: This is total mass diversion not BMW diversion under UK diversion targets. No data is available on the biodegradability of the outputs Source: Juniper analysis 1 Star screen screening system often used for separating and sizing organic material, which has high moisture content such as compost.

31 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-304 SUTCO D The bio-stabilised output that will go to landfill in Germany from the re-designed process at Erbenschwang will have to meet the German AT4 respiration limit and the strict levels of <18% TOC 1. For the purpose of calculating BMW diversion from landfill, this biostabilised output going to landfill will have a low BMW content. This means that if the RDF outputs are utilised as fuel, Sutco s new process could have a high BMW diversion performance. Figure D226: The pre-sorting process and composting bays at Erbenschwang Source: Sutco Energy Requirements D The plant is a net energy user. Energy balance data was not made available for review. Process availability D Sutco s latest process configuration has not yet operated. Most of the significant changes are being made to the mechanical pre-processing of the waste and the posttreatment of the bio-stabilised output. However, these are areas in which Sutco have considerable experience (see Figure D229 and Figure D230); also the experience gained from the operation of the old Erbenschwang plant is directly relevant to the new process. We have summarised in Figure D227 the operational performance data from 1 TOC = Total Organic Carbon

32 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-305 SUTCO the old configuration at Erbenschwang. The data indicates that the system was operated consistently at about 75% of its name-plate capacity for six years. D The operators, EVA, explained to us that the apparent shortfall in capacity was not a result of problems with the process, but that the plant was designed to accommodate increases in waste arisings. Data we have reviewed shows that the overall waste sent for processing increased by about 10% from 1998 to 2003, but much of this was recovered for recycling before the MBT plant or sent directly to landfill. Figure D227: Actual throughput of waste processed at Erbenschwang Input to MBT plant, Tpa Design capacity utilised, % Input to plant, Tpa Design capacity utilised, % Year Source: Juniper representation of EVA s data Process Flexibility D The Sutco Biofix composting process has been used at a number of plants for treating separately collected biowastes. The company provided a list of at least six references utilising this system to treat biowaste that are in operation in Germany, Norway and Italy. The plants range in capacity from about 6,500 Tpa to 50,000 Tpa.

33 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-306 SUTCO Figure D228: Selected biowaste references using the Biofix composting technology Location Plant Capacity, Tpa Startup Stavanger, Norway 28, Viersen, North Rhine-Westphalia, Germany 25, Goch, North Rhine-Westphalia, Germany 50, Ratingen, North Rhine-Westphalia, Germany 25, Lochau, Saxony-Anhalt, Germany 6, Swisttal-Morenhoven, North Rhine-Westphalia, Germany 12, Source: Sutco D Sutco also has expertise with the mechanical equipment that is necessary for MBT plants and for refining the process outputs (e.g. to use as a secondary fuel). Figure D229 and Figure D230 summarise some of their experience with mechanical systems for processing waste. Figure D229: Selected RDF reference facilities Location Plant Capacity, Tpa Startup Delitzsch, Saxony, Germany 50, plant extended to 60,000 Tpa in 2002 after fire damage Erftstadt, North Rhine-Westphalia, Germany Krefeld, North Rhine-Westphalia, Germany 45, , Winschoten, The Netherlands 15 T/h 2002 Wiefels, Lower Saxony 40,000 of wood waste and 60,000 commercial waste 2004 Neuss, North Rhine-Westphalia, Germany Meschede, North Rhine-Westphalia, Germany 100,000 March ,000 May 2005 Source: Sutco Process Scale D The Sutco MBT process has only operated at the Erbenschwang plant. The plant that operated from had a capacity of 22,000 Tpa. The re-designed process will

34 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-307 SUTCO have a capacity of 40,000 Tpa. The original plant utilised a single pre-processing line and six composting bays. The new plant will also use a single pre-processing line but with eight bays for intensive composting and a further six bays for post-maturation. Each bay has a capacity of approximately 450 m 3. The scale up to 40,000 Tpa requires larger pre-treatment equipment but, from the reference list provided by Sutco for this review of pre-treatment plant they have built and equipment they have supplied, this scale-up is well within their capabilities. Figure D230: Selected mechanical sorting plants Location Plant Capacity, Tph Application Startup Gernsheim, Bavaria, Germany 90,000 Tpa Sorting plant for construction waste, industrial waste and bulky refuse 1996 Cologne-Niehl, North Rhine- Westphalia, Germany 660,000 Tpa Mechanical pre-treatment of domestic waste before incineration 2000 Essen, North Rhine-Westphalia, Germany 7 (c. 19,000 Tpa*) Sorting plant for yellow bag waste 2001 Hamburg, Germany 13 (c. 35,000 Tpa*) Sorting plant for paper and cardboard 2001 Rainham, UK 50,000 Tpa Materials Recycling Facility 2001 Cologne-Merkenich, North Rhine-Westphalia, Germany Troisdorf, North Rhine- Westphalia, Germany 14.5 (c. 39,000 Tpa*) 8 (c. 22,000 Tpa*) Automatic paper sorting plant 2002 Sorting plant for yellow bag waste 2002 Alton, UK 24 (c. 65,000 Tpa*) Materials Recycling Facility 2004 Greenwich, UK 22 Materials Recycling Facility 2004 Schwedt, Bardenburg, Germany 1,000 Tpd (c. 300,000 Tpa*) Waste paper recycling facility 2004 * Juniper calculation based on 9 hours of operation per day 300 days per year Source: Sutco Output Materials D Figure D231 gives the quantities of outputs that could be obtained from the Sutco MBT process. This gives some indication about the amounts of various streams that will have to be managed if this process is implemented for treating similar types of waste. D D Bio-stabilised output:the process is currently designed to produce a bio-stabilised output to meet the German AT4 respiration limits. In Germany the limits on the respiration activity of materials sent to landfill have been tightened. The new AT4 limits, which require that the bio-stabilised output has a

35 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-308 SUTCO respiration activity below 5 mg O 2 /g ds, will apply to all waste processing plants from June 2005; this is the main driver for the re-design of the process at Erbenschwang. Figure D231: Products based on plant processing 40,000 Tpa German residual MSW Products Tpa Application RDF (>80mm from Input separation) 16,000 could be upgraded for use as a fuel RDF (>50mm from refining of the outputs from the maturation plant) 3,680 could be upgraded for use as a fuel Ferrous metals 1,000 recycled Fluff 280 could be used as a fuel Composting losses 6,040 treated in biofilter before exhausting to atmosphere (RTO 1 system will be used in new plant to treat air from composting process) Bio-stabilised output 13,000 sent to landfill Source: Juniper analysis of EVA data D D RDF output: During our site visit, EVA informed us that during plant operation, the air separator was rarely used (see Figure D222). The RDF that was produced when the air separator was operating was sent to an off-site incinerator. No details about the composition of the RDF stream were provided for review and we understand that no formal off-take arrangements were in place for the RDF output. Because of the infrequent operation of the air separator at the original Erbenschwang plant, much of the high CV fraction was landfilled. From June 2005, landfilling of waste materials will be subject to limit values of <18 % TOC, which means that the landfilling route for high CV materials will not be a viable option at the new plant. From our discussions with EVA, it appears that incineration is to be the preferred disposal route for the RDF. To utilise the RDF as fuel it is likely that the high CV fraction will have to be further separated to reduce certain contaminants such as chlorine containing materials. Sutco has significant relevant experience in this type of post-separation, and from information the company provided for this review, we note that they have built a number of mechanical processing plants for producing RDF from MSW in at least three different EU Member States. Environmental Impact Wastewater Emissions D The process does not produce any leachate. Fresh water is added to the homogenising drum and can be added directly to the composting bays by means of the automatic Biofix turning machine. 1 RTO = Regenerative Thermal Oxidation

36 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-309 SUTCO Process Gaseous Emissions D The off-gases from the original Erbenschwang plant passed through an enclosed biofilter before being emitted to atmosphere via a small stack. All fugitive emissions from the plant were collected via a negative air system and also passed through the biofilter. D The new process plant in Germany will incorporate a Regenerative Thermal Oxidiser (RTO) to treat the off-gases from the mechanical pre-treatment part of the plant and the composting process. The exhaust gases from the secondary maturation and the postscreening areas will be treated via the enclosed bio-filter. Footprint and Visual Impact D The land-take of the 40,000 Tpa plant at Erbenschwang is 8448 m 2. This translates to a footprint of 0.21m 2 /Tpa. Despite the need for compost maturation, the land-take is low compared with plants that require a considerable land area for windrow composting and maturation. D All of the buildings at the original plant were low profile structures that produce a low visual impact (see Figure D220). The visual impact of the plant will increase because of the presence of a thin exhaust stack for the RTO (see Annexe A5). We have already discussed the potential implications if a similar type of off-gas treatment process is required in the UK (see Annexe B5). Costs D EVA reported that the current gate fees are 130/Tonne and 110/Tonne, including and excluding landfilling respectively. The cost includes the operation of the RTO. Outstanding Questions D We have not been able to review data on the following: The composition of the RDF stream sent for incineration; The energy balance for the Erbenschwang plant. Summary D Sutco has significant experience in building mechanical separation plants and equipment for processing various waste streams, and in supplying these types of equipment to MBT plants. Such experience is significant in designing MBT plants as many of the

37 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-310 SUTCO bottlenecks and processing issues are usually attributed to poor waste preparation and post-treatment of the outputs. D While the company has comparatively less experience with integrated MBT and a relatively low visibility outside the German market in the MBT sector, their only turnkey MBT reference plant has operated for six years and demonstrated a high level of availability. The co-operation we have received in preparing this review from the operators of this plant, EVA, suggests that they have confidence in the process and are now extending the plant and committing significant financial resources to the new development. D The process now being built will take some time before it can be regarded as commercially fully proven. Though the plant at Erbenschwang does not produce a high quality RDF because of the customer requirements, we would expect Sutco s experience in manufacturing RDF plants to be of relevance where there might be more stringent requirements on the composition of the RDF output from the process. This review was prepared in November 2004 based on information received during our site visit to the Erbenschwang plant in October 2004 and from further direct communication with the plant operator. The review was finalised in January 2005, following further clarification discussions with Sutco.

38 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-311 VALORGA VALORGA Summary of the process Valorga designs dry anaerobic digestion systems that have operated in a number of MBT plants in Europe. Below is the typical MBT configuration in which the Valorga AD process has been integrated. The main products are biogas, which is used to generate electricity, a bio-stabilised output and RDF. Type of process being marketed MSW Mechanical pretreatment Anaerobic Digestion Digestate stabilisation Fe & Non- Fe RDF Biogas to gasengines Bio-stabilised output Commercial status on MSW feedstock No plant yet built Pilot Plant Demonstrator plant Commercial plants Advantages Disadvantages Key advantages & disadvantages significant number of references treating MSW in at least five different EU Member States long experience with supply of their AD process well known system that has been the subject of a number of independent assessments process is a net energy producer did not respond to our enquiries Contact details Valorga International SAS, Parc du Millénaire - BP 51, 34935, Montpellier Cedex 09, France. Tel: Fax: Key contacts Bertrand Hyllaire Sales Manager b.hyllaire@steinmuller-valorga.fr

39 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-312 VALORGA Overview D Valorga International SA is a French based company that markets a dry single stage anaerobic digestion system that has been used in a number of MBT plants to treat MSW. Valorga was acquired by Steinmüller and known as Steinmüller Valorga. The name of the company reverted back to the original name after the restructuring of Babcock Borsig Power, the former parent company, which became insolvent. D The name was changed to Valorga International when the new shareholding arrangement was agreed in December 2002, under which Tecmed 1 and Hese Umwelt (see the Hese process review) each hold 40% of the shares. D Both Tecmed and Hese independently promote the Valorga process. Ros Roca (whose MBT process we have reviewed) was also previously licensed to market the Valorga AD process in Spain and Portugal, but we were informed by Ros Roca that this agreement is no longer active. D Despite our many efforts to obtain more specific process information from Valorga for our review, we have been unable to make contact with them. We have been told by industry sources that this might be due to the fact that the company is undergoing various changes and might be short on available resources to respond to our request for information. Unfortunately therefore, this review has had to be based solely on information obtained from our visit to one of Valorga s reference facilities, facilitated by Tecmed, as well as public domain information already held on our in-house database and that obtainable from Valorga s website and other public domain sources. Status of Technology D Valorga has been involved with the anaerobic digestion of waste since 1982 when they built a small pilot scale plant in Montpellier, France. A number of pilot studies were conducted between 1982 and 1988 in France and Belgium and the company constructed their first commercial AD plant to treat mixed MSW in Amiens, France in Since then, Valorga has supplied AD plants that operate within an MBT configuration to treat mixed MSW and residual MSW. They have also supplied plants to treat various separately collected organic wastes. D Despite some negative publicity as a result of an explosion at one of their digesters at an AD plant in La Coruña, Spain, the company has established a significant reputation in the marketplace. Valorga has supplied their dry AD technology process to at least seven MBT references in five different EU Member States, one of the most recent being installed at the MBT plant at Ecoparc 2 in Barcelona, which we visited in July T ecmed is the environmental services division of the large Spanish construction group ACS (Actividades de Construcción y Servicio), which merged in 2003 with Dragados a major Spanish company active in the waste management and environmental sectors.

40 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-313 VALORGA D The Barcelona facility that was constructed by Tecmed is well engineered but had only just begun seeding the digester when we visited the plant (Figure D232). The plant is designed to process 300,000 Tpa of MSW, with about 120,000 Tpa (c. 40%) of the input going to the anaerobic digestion process. A list of Valorga s MBT reference facilities is shown in Figure D233. Figure D232: MBT plant at Ecoparc 2, Barcelona (2 of 3 Valorga s digesters in foreground) Source: Photograph taken by Juniper during site visit Figure D233: Valorga s reference facilities Location Total plant capacity, Tpa Design capacity of the digestion plant, Tpa Type of waste input to the plant Startup Amiens, France 55,000 now 85,000 Mixed MSW 1987 extended in 1996 Tillburg, The Netherlands 52,000 Source segregated MSW (vegetable-garden-fruit) 1994 Engelskirchen, Germany 35,000 Kitchen and garden waste 1998 Freiburg, Germany 36,000 Kitchen and garden waste 1999 Geneva, Switzerland 10,000 Kitchen and garden waste 2000 La Coruña, Spain 182, ,000 Mixed MSW 2001 Cadiz, Spain 210, ,000 Mixed MSW 2001 Mons, Belgium 58,700 Sorted MSW (40%), biowaste 2002 Varennes-Jarcy, France 100,000 MSW (70%) and biowaste 2002 Bassano, Italy 52,400 MSW (84%), biowaste (15.5%), sludge (0.5%) 2003 EcoParc 2, Barcelona 265, ,000 Source segregated MSW 2004 Hannover, Germany 100,000 Source segregated MSW 2005 Beijing, China 100,000 MSW 2005 Shangaï town, China 240,000 MSW 2005 Source: Juniper database

41 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-314 VALORGA The Process D The Valorga AD technology has been integrated within a number of different process designs and has operated in at least seven MBT plant configurations (see Figure D233). Typically, the design to treat mixed MSW includes a mechanical pre-treatment stage to separate the organic fraction of the waste for digestion. Figure D234: Typical Valorga process concept MSW Bag opening and trommel screen Screen undersize Screen oversize Magnetic separator Ferrous metals Magnetic separator Ferrous metals Cyclone Light plastics Size reduction Trommel Density separator To digestion plant Screen oversize Residues Glass + stones Process water Heat & Power Boilers or gas engines Biogas to storage tanks Mixer Bio-stabilised output Off gases Anaerobic Digester Digestate Trommel Composting Screw Press Process water for reuse Residues Leachate KEY Recyclables Further upgrading Effluent Stream Residue Stream Heat and Power Source: Juniper s interpretation of information from the Valorga website and from other public domain sources

42 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-315 VALORGA D The digestion of this fraction is usually carried out over a minimum of about 25 days and the biogas yield is about 110 to 150 Nm 3 /tonne of input waste to the digester, depending on the type of waste. The dry solids content of the feed to the digester is in the range 25-40% D The biogas produced at Valorga s reference facilities has been utilised in various ways: to make high pressure steam via an on-site boiler; to generate electricity directly in gas engines; injection into the gas network after purification. D The air from the composting plant and fugitive emissions from the mechanical pretreatment process are collected and passed through a biofilter before venting to atmosphere. We were not able to identify how the biogas from the Valorga digestion process is cleaned before being used or how any liquid emissions are managed. D The dewatered digestate is normally treated using an aerobic composting stage to further bio-stabilise this output. In addition to generating biogas, the company s website indicates that the AD process can be implemented in various configurations which aim to produce high quality compost, a soil improver or a bio-stabilised residue for landfilling. Such different configurations which aim to produce different outputs are discussed in Annexe A. D It also provides a schematic of a typical configuration of their process to treat various waste inputs (residual, organic and green wastes). We have summarised this information (Figure D234) for handling the residual MSW input, which is the same as the process implemented at Amiens, France. At other MBT references, we understand that variations of this process concept have been implemented. Process Performance D The company did not respond to our request for specific process data to allow us to assess the performance of the Valorga digestion process for this review. Nevertheless, the technology has been the subject of a number of public domain publications and the company themselves provide an impressive amount of detail about their reference facilities on their website. We have summarised some of this information below.

43 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-316 VALORGA Figure D235: Summary of plant performance Location Digester capacity, Tpa Waste input No. of digesters Minimum retention time, Days Digester sizes, m 3 Biogas yield* Nm 3 /T Biogas usage Amiens, France 55,000 now 85,000 Mixed MSW ,400 3, High pressure steam for industrial use Tillburg, The Netherlands Engelskirchen, Germany Freiburg, Germany Geneva, Switzerland 35,000 Kitchen and garden waste 36,000 Kitchen and garden waste 10,000 Kitchen and garden waste , Injection into gas network , Electricity & heat , Electricity & heat , Electricity & heat La Coruña, Spain 142,000 Mixed MSW , Electricity & heat Cadiz, Spain 115,000 Mixed MSW , Electricity & heat Mons, Belgium 58,700 Sorted MSW (40%), biowaste , Electricity & heat 52,000 Source segregated MSW (vegetablegardenfruit) Varennes- Jarcy, France 100,000 MSW (70%) and biowaste NR NR NR NR NR Bassano, Italy 52,400 MSW (84%), biowaste (15.5%), sludge (0.5%) , Electricity EcoParc 2, Barcelona, Spain 120,000 Source segregated MSW , Electricity NR Not Reported * Biogas yield per Tonne of input to the digestion plant Source: Valorga s website ( D A mass balance for the Ecoparc 2 plant is given in Figure D236. Based on this mass balance we have calculated the mass diversion potential of this process, which along with the assumptions we have made in our calculations, are given in Figure D237.

44 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-317 VALORGA Figure D236: Mass balance for MBT plant at Ecoparc 2, Barcelona Organic fraction of MSW (100%) RDF (43%) Biogas to gas engines (6.6%) Mechanical Pre-treatment (including hand picking) Organic fraction (44.6%) Condensate (0.3%) Valorga s Dry Anaerobic Digester Plastic film (0.9%) Fe metals (3.3%) Mixer Coarse inerts & rejects (3.8%) Mixed plastic (PET, HDPE etc.) (1.3%) Non Fe-metals Paper & carton (0.2%) (1.4%) Glass (1.5%) Steam (1.5%) Digestate Dewatering Flocculant (1.0%) Wastewater (some recirculated as process water) (13.9%) Bio-stabilised Output (26.3%) Tunnel Composting Source: Juniper analysis of data provided by the plant operators during site visit Figure D237: Diversion potential based on Figure D236 Diversion Potential Minimum, % Maximum, % Basis of Estimation Percentage of the input waste diverted from landfill c. 27 c. 96 Min: Bio-stabilised output to landfill, RDF to landfill, all inerts landfilled Max: Bio-stabilised digestate reused RDF used as fuel, inerts landfilled. Note: This is total mass diversion not BMW diversion under UK diversion targets. No data was available on the biodegradability of the process streams. Source: Juniper analysis

45 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-318 VALORGA Energy Balance D Energy balance data obtained during our site visit indicate that the Ecoparc 2 plant will export approximately 11,000 MWh/year to the grid from a total electricity production of approximately 26,500 MWh/year (i.e. c. 42% of electricity generated is exported). Scale D The capacity of the MBT plants in which Valorga s system is being used range from 10,000 Tpa to 300,000 Tpa. In addition to their MBT supply, Valorga has a number of stand-alone AD plants processing segregated MSW and biowaste at capacities of up to 52,000 Tpa. From the data in Figure D235:, it can be seen that the company has designed digesters in various sizes and therefore could implement their technology for both small scale and larger scale projects. Outstanding Questions D Despite our many efforts to obtain more specific process information from this company for our review, we have been unable to make contact with them and as a result we have not been able to provide our analysis of a number of items, including: process availability; the performance of the digesters based on an assessment of the biogas yield; the composition and quality of the bio-stabilised output from the digestion process; the typical required land-take and visual impact of an MBT facility built around a Valorga AD process; cost information. Summary D Valorga should be considered a leading process supplier within the AD/MBT sector with demonstrated processing experience. As a result, it is likely that this technology would be a candidate for MBT tenders where an AD-based approach is attractive. It is unclear whether Hese, Tecmed or Valorga themselves would promote the technology in the UK market and it is also unclear which organisation a potential customer should contact as a possible supplier of an MBT plant. This review was prepared in November 2004 from various public domain sources including Valorga s website. We also obtained information during our site visit to a Valorga MBT reference facility at Eco Parc 2 in Barcelona in July This site visit was facilitated by Tecmed. Despite our many efforts to contact Valorga directly, we were unable to get any further information from the process company. The review was finalised in December 2004.

46 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-319 VKW VKW Summary of the process VKW promotes a composting process, which is being used to treat MSW in MBT configurations and various bio-wastes. The MBT reference plants in which VKW systems are being used produce a bio-stabilised output, which is used as a soil improver or landfilled. Some of the MBT reference plants also produce RDF as a major output. Type of process being marketed MSW Mechanical pre-processing In-hall composting process Fe & non-fe metals & other dry recyclables RDF Bio-stabilised outp ut Commercial status on MSW feedstock No plant yet built Pilot Plant Demonstrator plant Commercial plants Advantages Disadvantages Key advantages & disadvantages demonstrated on mixed MSW process designed for large scale applications relatively simple process to implement actively promoting their technology in the UK market turnkey MBT plant recently supplied by VKW but not as yet in full commercial operation process is a net energy user Contact details VKW Anlagenbau und Umwelttechnik GmbH A-6901 Bregenz, Weidachstraße 6, Austria Tel: Fax: Web: Key contacts Helmut Schneider Executive Secretary helmut.schneider@vkw.at

47 MBT: A Guide for Decision Makers - Processes, Policies & Markets Page D-320 VKW Overview D VKW Anlagenbau und Umweltechnik (VKW) is a 100% owned subsidiary of the Austrian provincial power company Vorarlberger Kraftwerke AG, which is itself 95.55% owned by the Province of Vorarlberg. In 1996 Vorarlberger Kraftwerke diversified into the waste and environment industries and acquired the engineering company Vogel & Müller and the Hubert Häusle Group, the largest regional waste management company in western Austria. In 2001 Vorarlberger Kraftwerke reported a turnover of 241M from its core energy businesses. D Vogel & Müller, founded in 1983, designed the flat windrow composting process that is now being marketed by VKW as an in-hall composting system. The composting process uses a patented compost turning machine that was formerly referred to as the KUM system: this device is now called the CTM system. D Prior to the acquisition of Vogel & Müller, the composting process was licensed to the Swiss company Bühler and sold under the name Wendelin. We understand that this company is no longer active. Figure D238: Part of the 'CTM' compost turning machine Source: Photograph taken by Juniper during Tufino site visit D We visited the reference plant in Tufino, Italy, which is being operated by the Italian company Fisia Italimpianti. The plant is well engineered and is housed in relatively substantial buildings. The composting process was fully operational during our site visit but we only had limited access to the mechanical pre-treatment part of the plant, which was housed in a separate building. We were informed that engineering work was in