Composting plant with closed reactors LE COCCINELLE. Entsorga Technology

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Entsorga Italia S.r.l. Strada per Castelnuovo S.,7 15057 Tortona (AL) P. IVA 01755850060 Tel.0131.811383 Fax 0131.873281 www.entsorga.it info@entsorga.

1 Entsorga Italia S.r.l. Strada per Castelnuovo S., Tortona (AL) P. IVA Tel Fax Composting plant with closed reactors LE COCCINELLE Entsorga Technology Summary Summary... 1 LE COCCINELLE COMPOSTING PLANT... 2 Reception and storage... 2 Structural material organic waste mixing phase... 3 Organics reception shed, mixture preparation and reactors loading... 3 Loading... 4 Fast bioxidation phase with Le Coccinelle technology... 4 Unloading and curing... 5 Refining phase... 5 Area for the composting plant which adopts Le Coccinelle module... 5 Le Coccinelle module... 6 Summary of the necessary support equipment... 7 Plant management costs... 7 Composting and Le Coccinelle Rev.B.doc 1/8

LE COCCINELLE COMPOSTING PLANT This document describes the phases necessary to obtain compost from organic matrices such as sludge from waste water treatment plants, separately collected bio-waste,

2 LE COCCINELLE COMPOSTING PLANT This document describes the phases necessary to obtain compost from organic matrices such as sludge from waste water treatment plants, separately collected bio-waste, wood and branches from parks and open spaces etc. Also included below is a general description of the equipment and devices for a plant adopting Entsorga technology Le Coccinelle to speed up the bio-oxidation phases. Reception and storage. Structural material storage and processing The structural material is typically made up of wood and branches from parks and open spaces, or from untreated wood, and can be collected and processed seasonally. The structural materials are delivered to the plant and stored in a specific area and here fragmented and ground by a grinder, rendering them homogeneous and of the correct size. As the grinding phase is a periodic and somewhat casual operation, it is advisable to rent the grinder. The fragmented material is then transferred to the mixing shed, where it is mixed with the organic waste. Composting and Le Coccinelle Rev.B.doc 2/8

3 Organics reception The organic mixture, which arrives at the composting plant, must be - ideally immediately mixed and loaded into the reactors in order to avoid the production of unpleasant odours. A composting system implemented with Le Coccinelle technology, which exploits the possibility of loading each reactor independently of the others, can be managed according to the daily delivery of organic waste, avoiding the storage of the material for more than one day. Structural material organic waste mixing phase The organic waste and the structural material are mixed together before being loaded into the reactors. The correct preparation of the mixture is vital to the composting process and the material must therefore be of the right composition and porosity. These characteristics encourage both the homogeneous oxygenation and the optimum oxidation of the organic substances. The mixing ratio of organic waste to structural material, in the case of incoming separately collected bio-waste, is 2 to 1 respectively. For other organic matrices, the ratio may vary slightly. For instance, sewage from water treatment plants is denser and thus requires more structural material. The organic structural material mixture can be prepared using a grinder mixer (those using an uneven-number of scrolls, powered either by an electric engine or by PTO). To mix a sewagesludge mixture it is advisable to use a rubber wheeled loader in order to maintain the distance between the interstices. The composition of the mixture can be controlled meticulously as the feed boxes are equipped with loading cells. Organics reception shed, mixture preparation and loading of reactors The shed adopted for the above-mentioned operations is characterised according to the materials to be treated. In the case of incoming separately collected bio-waste and sewage, the shed must be watertight and vacuum-operated and have padded walls and carriage entrances. A tensiostatic structure has recently been adopted to guarantee safe seal and reversibility assurance. These technical devices have been created for odour control. Air escaping from the shed must be treated using a bio-filter or scrubber in order to avoid unpleasant odours. The reception area can also be made using prefabricated concrete. The area must have a minimum surface of approximately 600 sq. m, to allow for possible manoeuvres of the wheeled loader which loads the shredder mixer as well as for the container. Here space must be reserved for the temporary storage of both the structural material and the organics; the internal height must exceed seven metres in order to allow for loading / unloading of the container. Composting and Le Coccinelle Rev.B.doc 3/8

Loading The empty reactor is loaded onto the lorry and transported into the shed. Here it is unloaded and placed on the floor, thus exposing the upper layer.

4 Loading The empty reactor is loaded onto the lorry and transported into the shed. Here it is unloaded and placed on the floor, thus exposing the upper layer. The loading of the container is automatically controlled by the extraction belt of the shredder mixer. It is important not to store the organic and therefore putrid waste, and procedures must be undertaken to ensure that the incoming organics are mixed and loaded in the container within the working day. As you can see from the attached Mass Balance, the dimensions of these areas have been calculated in order to facilitate this operation. Fast bioxidation phase with Le Coccinelle technology The process of composting begins with the rapid bio oxidation of the mixture in the reactors. As mentioned before, the reactor is positioned and linked to the process line. The connection to the reactor consists of : - 2 air pipelines (incoming and out coming) - pipe for biomass moistening - pipe for percolates collection - linking cable for the temperature probe. The rapid bio-oxidation of the mixture is implemented by blowing air into the mixture itself in order to provide the mass with the necessary amounts oxygen for the correct chemical reaction to occur. The rapid bio-oxidation process takes between 8-14 days, according to the desired stability of the material. The out coming air from the reactors is projected through the bio filter to render it odourless and is then released into the atmosphere. This process is controlled and managed by an automatic informative control system, which operates according to parameters set by the operator, the amount of incoming and out coming Composting and Le Coccinelle Rev.B.doc 4/8

5 air and biomass moistening. Once the material has undergone the initial phase, the operator need only undertake periodic controls to check the condition of the treated material. This information is available on the PC video, where a table displays all operation parameters (mass temperature, air capacity, steeping cycles, environment temperature, bio-filter humidity) and a graph shows the trend of these parameters. Should a problem arise, specific notification windows inform the operator about the anomalous conditions and suggest a solution to the problem. By the end of the rapid bio oxidation phase, the characteristics of the material will conform to international standards (I.R.D. < mg O2 /kg S.V.*h). Once the cycle has ended, the programme automatically stops the air flux in the reactor and informs the operator. Unloading and curing The line reactor is then disconnected, loaded onto the dischargeable lorry and brought to the unloading and slow maturation area. Unloading is facilitated by opening the back shutter and lifting the reactor. The unloaded material is now odourless and, in accordance with legislation, can be left to mature in the open air. The second phase of maturation is known as curing, or slow maturation, and occurs by overturning the bulk using a machine, by aeration of static bulks or with both operations of turning and airing. The curing phase can be implemented under a roof or in the open-air: in the latter situation, the cumulus should be covered by perspirant sheet in order to avoid unwanted steeping and washing away in case of rain; it is also convenient to avoid material dispersion in case of wind. In this case the outcoming material from the bio oxidation phase must be unloaded on a blown plateau where the process goes on with an aired maturation confined under the sheet. At the end of the above described oxidation phase, we can absolutely guarantee a high level of stabilization. According to the national legislation (D.M. 5/2/98), the total time for compost maturation must end minimum 90 days: if 14 days are necessary for the fast phase within the reactors, the remaining 76 days are necessary for the slow maturation which is subdivided between the aired maturation and the final one (as previously described). Refining phase At the end of the slow maturation, the material refining takes place: it consists of the separation of the unwanted components (if necessary) like glass, plastics and metals (by screeners) and of the screening of the compost itself (there are different screeners available on the market) to obtain the more suitable size, removing the bigger pieces which can be reused as structural material. The product can be sold unpacked or packed in big bags, in PTE bags, pelletized and then sold through the ordinary sale channels. Area for the composting plant which adopts Le Coccinelle module A composting plant based on Le Coccinelle technology with mobile reactors requires a limited surface (as you can see from the included planimetries) and the following areas and equipment: Storage and bio shredding of the structural material Composting and Le Coccinelle Rev.B.doc 5/8

6 Organic waste reception, mixing and reactors loading area (closed and vacuum-operated shed). Fast bio oxidation area, covered by Le Coccinelle modules: this area will be floored with concrete or asphalted. Aired maturation though airing plateau, with confined materials under specific perspiring sheets. Slow maturation area (it s possible to foresee a roof). Refining area of the matured product. Storage of the finished product. Suitable area for the manoeuvres of the fast bio-oxidation reactors. Eventual area for cleaning of motorvehicle wheels. Office for the plant management where the reactor control system must be placed. This can be set up with small sized prefabricated structures. Weighing machine for the lots of materials processed by the reactors, before and after the bio-oxidation phase. Drainpipes for percolate collection. This can however be suitably filtered and reused for the biomass moistening inside the reactors. Drain pipes for water rain collection. Enclosure and lighting. Fire-fighting system. Le Coccinelle module Le Coccinelle composting plant is a modular solution where each module is composed by eight (8) reactors (capacity: 25 m 3 each), by one (1) bio filter, airing system, pipelines and automatic devices, monitoring system of the process and control parameters. The modules are provided and assembled in the customer s yard and ready to be used. Expenses for the power supply connections, for the water necessary for irrigation and the percolate drain well and pipes will to be debited to the customer s account. The mixture treatment capacity of each module may vary from 3000 to 5000 tonnes / year according to the permanence times which depend on the type of mixture itself and on the desired stabilization degree from the fast oxidation phase. The module can be provided with different planimetric solutions (see attached designs for some typical arrangements). The area in front of the reactors necessary for the lorry manoeuvres must be 12 m wide, while 60 cm must be left between the reactors. Composting and Le Coccinelle Rev.B.doc 6/8

Summary of the necessary support equipment These are the devices and equipment necessary for the managing of the composting plant: A wheeled loader for moving the composting materials A mixer for the

7 Summary of the necessary support equipment These are the devices and equipment necessary for the managing of the composting plant: A wheeled loader for moving the composting materials A mixer for the mixture preparation to be loaded into the reactors, eventually equipped with belt system for the container loading. A suitably dimensioned lorry with dischargeable equipment for the movement of the loaded reactors (this service can be managed by a third party, typically the means of transport which already delivers the material). A bio shredder (eventual, as it is possible to rent the machine) for the structural material fragmentation. Plant management costs The mixing / loading and unloading phases last one hour for each reactor, and consequently per each treated material: two hours are therefore necessary for each reactor every 8 14 days. As already mentioned the plant management software requires the operator s intervention only at the starting phase of a new lot of material and for periodic controls on the correct working of the system. The airing system, for each module, has a continuous absorption of 4.5 kw approx.; the moistening system takes litres water per day per container. It s however necessary to say that it s possible to use the percolates for the mass irrigation during the bio oxidation phase, thus saving 80% of the water consumption. Composting and Le Coccinelle Rev.B.doc 7/8

8 COMPOSTING PROCESS FLOW CHART STRUCTURAL MATERIAL (wood-cellulose) FRAGMENTATION FRAGMENTATED MATERIAL ORGANIC MISTURE GRIND-MIXING FASE AND REACTOR LOADING AIR PURIFIED AIR CO 2 WATER VAPOR PERCOLATES BIO-FILTER PERCOLATES RESERVOIR PERCOLATES PERCOLATES ACCELERATED BIO- OXIDATION (14 days) H 2 O SATURATED AIR PERCOLATES OVERSCREEN WOOD AIR WATER PRIMARY BLOWED IN CURING AND SECONDARY STATIC (min. 76 days) AIR + CO 2 WATER VAPOR REFINING PHASE METALS PLASTICS OTHER FINISHED COMPOST LANDFILL REUSE Composting and Le Coccinelle Rev.B.doc 8/8

APPENDIX E COMPOSTING MADE SIMPLE WITH AG-BAG ENVIRONMENTAL S ECOPOD TECHNOLOGY

APPENDIX E COMPOSTING MADE SIMPLE WITH AG-BAG ENVIRONMENTAL S ECOPOD TECHNOLOGY Composting Made Simple with Ag-Bag Environmental s EcoPOD Technology A s the world s population grows along with the volume