ECONOMIC AND ENVIRONMENTAL ASSESSMENT OF SLUDGE TREATMENT IN REED BED SYSTEMS 28 YEARS OF EXPERIENCE Steen Nielsen ORBICON Ringstedvej 20 Roskilde, 4000 DENMARK smni@orbicon.dk New Zealand Land Treatment Collective Annual Conference 2016-16th - 18th March, Gisborne Steen Nielsen - smni@orbicon.dk 05/02/2016 1 Steen Nielsen Senior Manager Sludge treatment in Reed beds systems (STRB) STRB experience: 28 years (employed in Orbicon for 28 years) International papers: more than 30 papers Member of IWA - Group:Wetland Systems for Water Pollution Control Member of : The scientific comity for 16. Conference Wetland Systems for Water Pollution Control Member and one of the founding fathers of GWT: Global Wetland Technology Responsibilities and key tasks 1. Product development and research 2. Dimensioning, Design, Construction, Running in and Operations 3. Publications and Conferences 4. Sales and marketing References: More than 50 systems in Denmark, Sweden, Norway and England World largest system for treatment of water works sludge (Hanningfield (UK) Research projects with Danish DEPA and with more than 5 International Universities incl. cooperation with a number of research institutions and to supervise researchers and PhD students. 2 SLUDGE TREATMENT IN REED BED SYSTEM (STRB) Large scale system and esperience through 28 years Sorø Sludge Treatment Reed bed System 28 Years of experience with Sludge Treatment Reed Bed Systems (STRB) Helsinge Sludge Treatment Reed Bed System Steen Nielsen ORBICON, Ringstedvej 20, Roskilde, 4000, DENMARK smni@orbicon.dk 550 tonnes of dry solids per year 10 basins 42.000 PE 630 tons ds per year Activated sludge 14 Basins Greenhouse/Stockpile area Into service 10 Basins (1996) 4 Basins (2013) 2.2 Ha 05/02/2016 3
System Proces and Product Long-term sludge reduction in reed beds Overall funtionality Dewatering Draining Evapotranspiration Aeration Mineralisation Sizing Sludge production (tonnes of dry solids per year) Loading pipes Sludge quality (fat-content, CST) Sludge type (type of production) Climate (evaporation) Periods of operation Area loading rate Number of basins Basin capacity
Aeration Pipes VALVE BUILDING BUFFER TANK The operation of WWTP The distance Mix more than one type of sludge Pump Pump capacity Sludge distribution (hole surface) Batch size Quota Basin area (no. of loading pipes)
THE REEDS Quality of the reeds Establishment of the reeds Weed control Effect of sludge Operations and Control Scada Management/Regulation Monitoring/Supervision Data handling OPERATION AND CONTROL Overview
Helsinge STRB - Sludge residue height Generel Maintenance General areas (green keeping) Scale Poles Ventilation Equipment Sludge pump Fences, Buildings, Valve, Wells, pumping stations Weeds Sludge residue height in Basin #1, 1997-2011 - Yearly growth of 13-15 cm 17 Winter Operation Tidaholm STRB (Sweden) Physical frames Operation Effect of frost Quality of the sludge after treatment
Legislation on heavy metals and hazard organic compound in sludge for agricultural use Sludge residue quality parameters prior to emptying (± standard deviation) and Danish legal limits. European Legislation Danish Legislation Limit values 86/278/EEC EU Directive ENV. E 3 (2000) Working document on sludge., 3rd draft BEK No. 1650 of 13/12/2006 Heavy metals (mg pr. Kg DS) (mg pr. Kg DS) (mg pr. Kg DS) (mg pr. Kg TP) Cadmium (Cd) 20-40 10 0,8 100 Copper (Cu) 1000-1750 1000 1000 - Nickel (Ni) 300-400 300 30 2500 Lead (Pb) 750-1500 750 120 10000 Zinc (Zi) 2500-4000 2500 4000 - Mercury (Hg) 16-25 10 0,8 200 Chromium (Cr) - 1000 100 - Organic contaminants (mg pr. Kg DS) (mg pr. Kg DS) (mg pr. Kg DS) (mg pr. Kg TP) LAS (Linear Alkylbenzene Sulfonate) PAH (Polycyclic Aromatic Hydrocarbons) NPE (Nonyl Phenol Ethoxylate) DEHP (di-2-ethylhexyl phthalate) - 2600 1300 - - 6 3 - - 50 10 - - 100 50 - The data presented are average values based on 8-10 pooled samples Steen Nielsen - smni@orbicon.dk 05/02/2016 21 Sludge residue quality parameters prior to emptying (± standard deviation) and Danish legal limits. Sludge residue quality parameters prior to emptying (± standard deviation) and Danish legal limits. The data presented are average values based on 8-10 pooled samples The data presented are average values based on 8-10 pooled samples
Reduction of pathogenic micro-organisms Section of sludge residue and sampling sites Salmonella (CFU/g ds) Depth: 0 10 CFU/g ds (LOG) 6 Salmonella : 0-10 cm (Helsinge Sludge Reed Beds - Basin no. 8) 5 4 3 Sludge residue 2 Filter 1 0 0 5 10 15 20 25 30 35 Time (days) Enterococci (CFU/g ds) Depth: 0 10 CFU/g ds (LOG) 8 7 6 5 4 3 2 1 0 0 20 40 60 80 100 120 Time(days) E. Coli CFU/g ds (LOG) 10 9 8 7 6 5 4 3 2 1 0 E. coli : 0-10 cm (Helsinge Sludge Reed beds - basin no. 8) 0 20 40 60 80 100 120 Time (days)
Mineralisation of digested sewage sludge Kallerup STRB (Denmark) NPE (sum) (mg/kg DS) Sludge Reed Bed 70 60 50 40 30 20 10 0 0 50 100 150 200 250 300 days NPE (Nonyl Phenol Ethoxylate) Loaded mass (kg) 0.3 Remaining mass (kg)0.02 Reduction (%) 94 6000 5000 4000 3000 2000 LAS (mg/kg DS) Sludge Reed Bed Environmentally friendly operation LAS (Linear Alkylbenzene Sulfonate) Loaded mass (kg) 24.5 Remaining mass (kg)0.4 Reduction (%) 98 1000 0 0 50 100 150 200 250 300 days Environmentally friendly operation Operational reliability Long-term sludge solution Flexible operation No problems with winter operation Very low operational costs and low energy Release of waste water treatment capacity Environmentally friendly operation Better working environment Non-polluting dewatering Reduction of CO2 and NOx emission Reduction of transportation costs Mineralisation of Hazardous Organic Compounds Good reduction of the Pathogenic micro-organisms No use of chemicals (polymers) for dewatering Recycling of the sludge residue
Rudkøbing STRB (Denmark) Trial pits and inspection Emptying Re-generation of the reeds recycling/reuse Nakskov STRB (Denmark) Emptying Final Disposal Rudkøbing STRB (Denmark) Emptying and regeneration
Skovby STRB (Denmark) - Emptying Skovby STRB (Denmark) Regrowth of reeds 24. August 2006 9. September 2006 31. July 2006 Emptying Photo: Orbicon Nordborg STRB (Denmark) Emptying May 2011 Nordborg STRB (Denmark) Emptying (May 2011)
Nordborg STRB (Denmark) Stock Pile area Recycling in August/September 2011 Emptying Re-generation of the reeds recycling/reuse Helsinge STRB (Denmark) Green house Solar Drying of Sewage Sludge Dehua Site Visit Helsinge STRB (Denmark) 42.000 PE 630 tons ds per year Activated sludge 14 Basins Greenhouse/Stockpile area Into service 10 Basins (1996) 4 Basins (2013) 2.2 Ha Orbicon 44
Helsinge STRB (Denmark) Helsinge STRB (Denmark) Green house Solar Drying of Sewage Sludge Steen Nielsen - smni@orbicon.dk 05/02/2016 46 Helsinge STRB (Denmark) Stock Pile area Recycling in August/September 2015 20 years of experience with the emptying and recycling of STRB-biosolids More than 30 systems and 200 basins have been emptied Over 130,000 tonnes of biosolids from STRBs have been spread onto nearly 10,000 hectares of Scandinavian agricultural land over the past 20 years. No reports of disturbances to natural wildlife, fauna or agriculture (no regrowth of reeds) Steen Nielsen - smni@orbicon.dk 05/02/2016 47 Steen Nielsen - smni@orbicon.dk 05/02/2016 48
Life cycle Sludge on agricultural land RECYCLING Combined system and Test system Kallerup STRB (Denmark) Sludge Treatment and Storm Water Basin Kristianstad STRB (Sweden) Trial System
Hanningfield Water Works and the water works sludge lagoon (United Kingdom) Treatment of Water Works sludge Area for Reed Bed System Old sludge lagoon Sludge lagoon Water Works Sludge Treatment Test System Hanningfield Water Works system (UK) Hanningfield STRB (United Kingdom) 1,275 tonnes of dry solids per year (16 basins (4.2 Ha) Reservoir Facts Capacity Maximun depth Surface area : 27 billion litres/year : 17 metres : 354 hectares Water Works Facts Water production Producton of sludge : 150 million litres/day : 1,275 tones ds per year
Hanningfield (England Water Works Sludge) Sludge treatment Reed bed System Hanningfield (England Water Works Sludge) Sludge treatment Reed bed System Steen Nielsen - smni@orbicon.dk Steen Nielsen - smni@orbicon.dk Sludge Treatment Reed Beds Systems Greve STRB (Denmark) References 60,000 PE 1,000 tonnes of dry solids per year 10 basins (3.3 ha)
Kolding STRB (Denmark) Skøvde STRB (Sweden) 125,000 pe 2,200 tonnes ds/year Activated sludge 66% - Digested sludge 33% Into service 1998 and 13 basins - 6.2 Ha Skøvde Sludge Treatment Reed bed System 1,200 tonnes of dry solids per year - 10 basins 62 Sorø STRB (Denmark) Helsinge STRB (Denmark) Sorø Sludge Treatment Reed bed System 550 tonnes of drysolids per year - 10 basins Helsinge Sludge Treatment Reed bed System 630 tonnes of dry solids per year - 10 basins 2012
Rudkøbing STRB (Denmark) Esbjerg STRBs (Denmark) Rudkøbing Sludge Treatment Reed bed System 250 tonnes of dry solids per year 8 basins Esbjerg STRB is the largest system in Denmark (Consultant: NIRAS) WWTP east (125.000 PE) WWTP west (290.000 PE) 2.800 tons ds per year Economy
Thank you for your attention Steen Nielsen Orbicon A/S Ringstedvej 20 DK 4000 Roskilde Phone +45 46 30 03 10 Fax no.+45 46 30 03 11 E-mail: smni@orbicon.dk