A -M WRF Solids Alternatives. Joint City Council Meeting

Transcription

1 A -M WRF Alternatives Albany -Millersburg Joint City Council Meeting January 18, 2018 Overview Background Selection Criteria Alternatives Analysis Recommendation 1

2 Background A -M WRF began operating 2009 Replaced WWTP from 1950' s Treatment produces clean water, solids Excellent water quality to TWG, river usually stabilized to produce biosolids Class B apply on limited crops Class A higher treatment, unrestricted use Unstablized solids produced at WRF Consultant; tx Background WRF designed around Cannibal reduction process (90%) Reused tanks for minimal aerobic digestion Decommissioned anaerobic tanks Paired with Vertical Loop Reactors (VLR) 2

3 Cannibal Reactors/ Aerobic Digesters Old Anaerobic Tanks 3

4 Vertical Loop Reactors ( VLR) Water Reclamation Facility Dewatering and Biosolids Storage Cannibal Reactors/Aerobic Di esters Vertical Loop Reactors Decommissioned Anaerobic Di esters 4

5 ym;_. iii ' WRF Schematic Ek io Influent Pumping & Screening Grit Removal Vertical Loop Reactors Secondary Clarifiers Chlorine Contact Basins TWGIRiver Discharge Return Sludge Landfill Cannibal Storage) Dewatering Background Cannibal failure Settled with Siemens $4. 3M Handling/landfill cost $ 650, 000/yr Not paying for treatment (energy savings) dewatering equipment replacement 5

6 Background CH2M Hill Alternatives Analysis 2012 Screening of all solids treatment alternatives Analysis of 4 select options Report never finalized GORE Composting Pilot Study 2015 Year-long study Composted WRF solids result in Class A material Dewatering Equipment Pilot Studies Background 2017 Update screening of all options Analysis of select alternatives Preferred alternative Recommend path forward 6

7 Selection Criteria Phasing potential Technology maturity Potential to reuse existing facilities Odor potential Cost (capital and operational) Treatment performance Complexity Environmental impact Beneficial use of end product (Class A vs Class B) i Identified Alternatives Four broad alternatives Identified A. Existing process/landfill disposal B. Existing process + C. Aerobic Digestion D. Anaerobic Digestion Class A Treatment 7

8 1 vti. Evaluation Criteria Economic Capital costs Operation and maintenance Non -economic Odor potential Neighborhood impact Permitting Reliability and ease of operation Regulatory reliability Worker safety Impact to existing treatment facilities Siting/ land acquisition Marketability of final product Phasing 574 Dewatering Dewatering improvements are needed for all solids alternatives 8

9 Class A Alternatives Three alternatives considered Composting Lime -heat pasteurizatio Thermal drying Courtesy of Cedar Grove Courtesy of RDP Technologies 4 Composting Preferred Class A Treatment Economic Evaluation (Present Worth) Composting ($ $ 20.9 million) Dryer ($ $ million) Lime Heat Pasteurization ($ $ million) Non -economic Criteria Ranking Composting: 42 Dryer: 34 Lime Heat Pasteurization: 30 9

10 may, + s^ Detailed Alternatives Analysis Existing Process ( Landfill vs Class A) Aerobic Digestion ( Class B vs Class A) Anaerobic Digestion Primary treatment (Class B vs Class A) No primary treatment (Class B vs Class A) Is ing rocess Class A Treatment 111 r4-4 Influent Screening Pumping 8 Grit Removal Vertical Loop Reactors Secondary Clarifiers Chlorine Contact Basins TWGIRiver Discharge Return Sludge Cannibal Storage) Dewatering r Class A Biosolids Treatment y Class Beneficial Use Landfill Unclassified yennedy/jenks 10

11 Aerobic Digestion Class A or Class B Treatment 41: 1 Ci* Influent Pumping & Screening Grit Removal Vertical Loop Reactors Secondary Clarifiers Chlorine Contact Basins TWGIRiver Discharge Return Sludge Thickening Aerobic Digestion Class B) 4 Dewatering Class A Biosolids Treatment I* ClassA Beneficial Use Class B Beneficial Use V.. Anaerobic Digestion with Primary Treatment El* Z4 Influent Sc eening Primary Pumping & Grit Removal Treatment Vertical Loop Reactors Secondary Clarifiers Chlorine Contact Basins TWG/ River Discharge Return Sludge yr MOClass A Beneficial Use Class A Thickening Anaerobic Digestion Class B) Dewatering Biosolids Treatment Class B Beneficial Use 11

12 r Anaerobic Digestion without Primary Treatment Influent Screening Vertical Pumping 8 Loop Grit Removal 4 Reactors Secondary Clarifiers Chlorine Contact Basins TWGIRiver Discharge Return Sludge Thickening Anaerobic Digestion Class B) Dewatering r Class A Biosolids Treatment ClassA Beneficial Use Class B Beneficial Use Detailed Alternatives Evaluation Economic Comparison Capital O& M Non -Economic Comparison 12

13 Economic Comparison Alternative Capital Cost;,. million O& M; 6million Present Worth, million L Existing process Landfill ClassA- composting Aerobic digestion Class B ClassA- composting Anaerobic digestion w/ primary treatment) Class B 29: Class A - composting Anaerobic digestion w/out primary treatment) Class B Class A - composting Non Non - - Economic Economic Comparison Comparison Considerations Considerations Odor Odor potential potential Alternative Alternative F Score Neighborhood Neighborhood impact impact Permitting Permitting Reliability Reliability and and ease ease of of operation operation Regulatory Regulatory reliability reliability Worker Worker safety safety Impact Impact to to existing existing treatment treatment facilities facilities Siting/ Siting/ land land acquisition acquisition Marketability Marketability of of final final product product Phasing Phasing Existing process Landfill 25 Class A - composting 40 Aerobic digestion Class Class BB Class Class A A - - composting composting 41 Anaerobic digestion w/out primary treatment) Class B 36 Class A - composting 38 13

14 lay Preferred Alternative Existing Process + Class A (Composting) Economic: Second least cost Non -economic: Second highest ranked Most easily phased in Highly marketable end product Cities have working experience with composting Least disruptive to current operations k Preferred Alternative Recommendation Replace dewatering equipment (-$ 3.2M) Develop a small scale composting facility 15. 7M) Add capacity over time 14

15 Recommendation Evaluate the composting option further with a pre -design effort. Preliminary Design to evaluate: Potential sites Phasing plan Permitting/ Regulatory Bulking material/ end- use markets Layout/ refine costs Solicit proposals Seek Council authorization Complete Pre -design in 2018 Questions? 15