UF Water Reclamation Facility
The water reclamation facility on the University of Florida campus serves as the treatment facility for all wastewater coming from the campus. At the time of this tour (Summer B) about 1.5 million gallons of wastewater enter the facility daily. In the fall or spring about 2 to 2.5 million gallons of wastewater enter the facility daily. Special events such as football games increase the flow to about 3 million gallons for that day. Composite samples are taken daily of both influent and effluent to test whether or not the facility is in compliance with the permit standards. Nutrient levels, metals and bacteria are some of the things the daily samples show.
The wastewater entering this facility is called raw influent and is pretreated to remove any debris that may be in the water. The inert material also drops out of the water at this stage and is put into a dumpster. The ΒΌ inch screen cannot remove all undesired material, therefore some floatables can be found in the next stages of treatment. Once the influent is filtered, in moves into the biological nitrogen removal (BNR) cycle. This cycle begins with anaerobic selectors that do not contain dissolved oxygen, but do contain facultative bacteria. The bacteria are stressed in this stage so that they release phosphorous while being constantly mixed. When the wastewater is nitrified the bacteria uptake twice as much phosphorous as was released earlier, but dissolved oxygen is required. The next selectors carry out the Kruger process where nitrification and denitrification are always occurring, and nitrogen is being driven out of the water. Roters allow for air to get into the water for nitrification and can also remove air from the water for denitrification.
After the influent passes through all of the selectors it enters into the two circular secondary clarifiers. Here the solids settle out of the water onto the bottom and form sludge. Half of the sludge is removed (waste activated sludge) and digested at the GRU facility, and half of the sludge is taken back to the head of the treatment cycle to replenish the bacteria supply (returned activated sludge).
After this process the water is pumped into sand filters where more suspended solids are removed. The permit allows for TSS levels to be no higher the 5 ppm; if the plant is out of compliance they add polyaluminum chloride to flocculate the remaining solids for removal. Then the water moves into the two chlorine contact chambers made of five raceways each. The sodium hydrochloride disinfects the water killing pathogens, and must have at least 15 minutes of contact time with the water. The main sampling is done at the end of this process four times per week, and the water must contain at least 1 ppm chlorine. If the water/effluent is within the permit standards it can then be transferred to the large circular holding tank. It usually takes 24 hours for influent to be treated into effluent and put into the final holding tank. If there is ever a time when the water does not meet the standards, it flows into the larger outer holding tank and is later pumped back to the start of the system once the standards are met.
The whole facility is monitored and operated from a control room in the main building. The final water/effluent is used for irrigation around campus, but it could technically be cleaned further into drinking water. There is an extra holding tank in the commuter lot, and at times the final product can be injected into the groundwater directly.