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Solids Processing

DAFT (Dissolved Air Floatation Thickener)
In this process, some of the sludge and scum from the final clarifiers are thickened before being pumped to the digesters for the next step in the treatment process. The DAFT removes suspended solids (SS) as wastewater enters the DAFT tanks, fine air bubbles rise to the surface and attach themselves to the SS along the way whereby the surface is skimmed to remove the collected SS and sends them to the digesters for further treatment.

Anaerobic Digesters
In the digesters, the thickened solids are processed in an anaerobic (no oxygen) state at temperatures of preferably 32 ºC – 35 ºC which initiates a biological and chemical breakdown of the solids. Since there is no oxygen certain types of microorganisms proliferate and these are called anaerobes. These anaerobes live without us supplying them oxygen because they get all the oxygen needed to live from the waste supplied to them. They do this by breaking down the wastes into simpler components and using the oxygen as a by-product of the breakdown. The breakdown of the solids produces a type of sludge called biosolids and gasses as by-products.

  • Fertilizer (biosolids) - High in phosphorus and ammonia and used to spread on farmland to enhance the quality of the soil and reduce the amount of additional fertilizer needed by farmers. This fertilizer must meet strict guidelines set by Alberta Environment and strict third-party lab testing ensures compliance.
  • Methane gas (CH4) - which is used to power large air compressors (blowers). The remaining methane is burned through two flare stacks.

Biosolids Lagoons
The solids from the digesters are pumped to holding lagoons where further separation of the solids and water takes place through gravity alone. After this treatment and separation the water is returned to the WWTP for further processing before being released to the river. The solids (fertilizer) are retained in the lagoons for the entire year before being spread on farmland in Fall.

Every year, on average the WWTP produces 3,000 dry tonnes of biosolids which are recycled back as fertilizer and applied to farmland.

Equalization Lagoons
These lagoons, originally used as the first form of treatment by The City of Red Deer, have generally become obsolete due to Red Deer's rapid growth and the newer treatment technologies available. Mechanical treatment was introduced in 1973 and today the use of the lagoons is to provide a holding place for wastewater in the event of heavy rainstorms or power outages when the main WWTP cannot be used. When plant flows return to normal, this extra wastewater is returned for processing.

Source Control Program
This program is a proactive, pollution prevention initiative established in 2003 to protect:

  • The Red Deer River and Creeks feeding into it
  • Wastewater Treatment Plant
  • Physical structure of the Wastewater Collection system
  • Wastewater employees as well as the public
  • To monitor our sanitary sewer use customers and make them aware of the Sewer Use Bylaw and the effects they have on the Wastewater Collection system and WWTP.

Spill Response Plan
The City of Red Deer has implemented a Spill Response Plan for spills and releases which may cause adverse effects on the Environment or impact the storm water or Wastewater Collection systems. Environmental Services (Source Control) responded to 46 reported spills and releases in 2007 involving the storm water and Wastewater Collection systems with the possibility of ground contamination. Illegal dumping into the storm water system continues throughout The City of Red Deer. This is of great concern as it’s a direct route into the Red Deer River.

For further information please contact the City’s Source Control Inspector at 403-309-8574.

FOG Station
Fats, Oils and Grease (FOG) can cause your household sewer line to plug causing your home, in particular your basement to overflow with sewage. To stop this from happening in your sewer lines you must prevent FOG from entering. Here’s how to help.

  • Collect your waste cooking oil and grease in containers with lids
  • Don’t pour fat, oil or grease down any drain
  • Wipe out pots and pans before washing and dispose of in garbage
  • Teach everyone in the family to follow these practices

To work cooperatively with businesses and industry in Red Deer and to protect the environment of negative impacts which FOG plays on the collection system the City of Red Deer has established a Liquid Waste Disposal Station location at the Wastewater Treatment Plant for the proper disposal of fats, oils and grease.

For more information please contact the City’s Source Control Inspector at 403-309-8574.

Liquid Waste Disposal Station
This station is located at 7890 – 40th Avenue on-site of the WWTP.

The City of Red Deer, to work cooperatively with Industrial and Commercial businesses provides a Liquid Waste Disposal Station as a service for waste generators and liquid waste haulers from the City and surrounding areas.

The City of Red Deer accepts the following wastes which include:

  • Septic tank waste
  • Portable and RV toilet waste
  • Waste Activated Sludge from small residential Water or Wastewater Treatment Plants(Special requirements pertain to the acceptance of this type of waste)
  • The City of Red Deer’s Utility Bylaws 3215/98 does apply to Wastewater being hauled to the Wastewater Treatment Facility.

For further information please contact the City’s Source Control Inspector at 403-309-8574.