Performance History and Discussion
The Farmington Water Pollution Control Authority (FWPCA) selected In-Pipe Technology to improve the performance of the WWTP by reducing sludge production and improving the nitrogen removal efficiency of the treatment process. Additional benefits of In-Pipe service include improving effluent water quality, reducing energy consumption at the plant and protecting the collection system by removing fats, oil and grease (FOG) and controlling hydrogen sulfide production.
In-Pipe started the first of three dosing unit installation phases in early April 2010. Within 30 days all dosing units were installed and complete treatment began. The performance metrics are calculated by comparing plant performance observed during May through July of 2010, to the same months of the year in 2009.
Sludge disposal costs in the northeast region are among the highest in the country. During the year prior to In-Pipe’s implementation, the FWPCA spent nearly $285,000 on sludge hauling and disposal. As of July 31st the FWPCA has produced 22 fewer wet tons of sludge than the same period in 2009. As a result, InPipe has reduced the cost for the FWPCA to handle, transport and dispose of sludge by nearly 9%.
Since the Connecticut DEP established the Nitrogen Credit Exchange (NCE) program in 2002 to reduce nutrient loads entering Long Island Sound, the plant has been pressured to reduce nitrogen discharged with the plant effluent into the Farmington River. In 2009, the FWPCA was forced to pay nearly $22,000 for nitrogen credits and as the program continues, the pressure escalates as a result of more stringent discharge limits and increased cost per credit. In-Pipe lowered the effluent total nitrogen by 34%, from
293 average pounds per day in 2009, to 194 pounds per day in 2010. Since the NCE limit for the Farmington WWTP is 203 pounds of nitrogen per day, the FWPCA is now on track to sell nitrogen credits instead of buy them.
In addition to reducing sludge production and improving nitrogen removal efficiency at the WWTP, In-Pipe has also impacted the plant in the following ways during just the first three months of collection system treatment.
- Biochemical Oxygen Demand (BOD) daily average
- Influent BOD decreased 24% from 13,560 lbs to 10,241 lbs
- Effluent BOD decreased 16% from 240 lbs to 200 lbs
- Total Suspended Solids (TSS) daily average
- Influent TSS decreased 12% from 16,139 lbs to 14,223 lbs
- Effluent TSS decreased 12% from 102 lbs to 89 lbs
In-Pipe has improved WWTP operations within just the first three months of treatment. Performance will continue to improve over the next few months as the biofilm conversion process completes…stay tuned for additional project updates.
Project Installed: April 2010
Plant Size: 5.65 MGD
- Reduce Sludge Disposal
- Improve Nitrogen Removal
- Improve Effluent Water Quality
- Reduce Energy Consumption
Performance Summary In just the 3 months since Install:
- 9% Sludge Reduction
- 34% Reduction Effluent TN
- 24% Reduction Influent BOD
- 16% Reduction Effluent BOD
- 12% Reduction Effluent TSS
Financial Payback: $10,600
Calculated Savings May-July 2010:
- $2,250 Sludge Hauling
- $8,350 Nitrogen Credits