Highland Creek Wastewater Treatment Case Study
•Case Study: Highland Creek Wastewater Treatment
The Highland Creek Wastewater Treatment Plant serves a population of 310,000 people on roughly 35,000 acres in the Municipality of Scarborough, Ontario, adjacent to Toronto, Canada. The 145.8 acre facility is managed by the City of Toronto Works Department and has been in operation since 1956. The plant has a treatment capacity of 48 million gallons of wastewater per day.
The wastewater treatment process begins at the Head House where grit and inorganic materials are screened out. The next step is Primary Sedimentation where the flow enters large tanks, the velocity is slowed, and solids settle to the tank bottom. These solids are then pumped out to a sludge blending tank. Next aeration occurs when effluent from a Primary Sedimentation tank is mixed with return activated sludge from final sedimentation tanks into aeration tanks. The 16 aeration tanks have a total volume of 53,000 cubic meters. The mixed liquor from the aeration tanks then flows into one of 16 final sedimentation tanks where sludge settles. Chlorine then disinfects the final effluent to destroy organisms before discharge into Lake Ontario. Finally, the sludge is allowed to settle and thicken before it is dewatered and incinerated.
The process involves an extensive methane gas generation distribution network. Therefore, reliable and accurate gas detection is of paramount concern for the protection of the plant's people and equipment, as well as maintaining sewage services for local residents.
Problem
- Wastewater methane gas build-up
- Low sensitivity and excessive drifting
- Maintenance intensive resulting in excessive man-hours
- Short sensor life cycle
- Need rapid troubleshooting
Solution
- Combustible gas detectors, controllers, accessories
- Low drift increasing both reliability and intervals between calibration cycles
- Non-intrusive one-man calibration
- Poison resistant sensors for longevity
- Superior diagnostic capabilities
•Case Study: Highland Creek Wastewater Treatment