Our Wastewater Systems: The Closed-Loop Wastewater Treatment System


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Our Wastewater Systems: The Closed-Loop Wastewater Treatment System

It is very important to understand your facility’s water quality requirements so that you will know how to effectively and quickly remove contaminants. We can design an entire system that focuses on filtration, the pre-separation process before water enters the system. It is vital to focus on this part of the process to optimize overall performance. When pre-separation is included in the design, the results are cleaner processed water, which means minimal maintenance costs due to longer filter life, fewer pump failures, reduced sediment build up, and controlled chemical consumption. Using the wrong type of filter system can result in expensive maintenance costs down the road. Evans Equipment and has three different wastewater systems to meet your needs: the closed-loop wastewater treatment, discharge water treatment systems, and filtration systems.

Closed-Loop Wastewater Treatment

A zero discharge system (or closed loop system) is designed to recycle, filter and reuse the water that is used by a pressure washer or steam cleaner. It is different from the other two Wastewater Treatment Systems because it allows the user to re-use the water because when the water is treated and pumped back to the pressure washer.

How the Closed-Loop Wastewater Treatment System Works:

  1. All wash water is captured into the trench drains or sump and gravity flows directly into the catch basin. The catch basin serves as a primary location to settle suspended solids.
  2. Water is then pumped from the catch basin to the inlet side of an above-ground aluminum oil/water separator. The oil/water separator serves as a secondary location to settle any remaining suspended solids.
  3. The water then flows from the first compartment of the oil/water separator to the second compartment through a baffle with a stand pipe, which mechanically separates the oil from the water by trapping the oil in the first compartment.
  4. The Evans Water Treatment System then pumps the water from the second oil/water separator compartment into the first 600 gallon cone-bottom tank. The first 600 gallon cone-bottom tank continues to settle any remaining suspended solids, but also contains live microbes that are engineered to consume oil & grease or any hydrocarbons from the water. The tank is supplied with aeration to provide oxygen needed by the microbes to colonize and multiply while consuming oil & grease. The PH of the water is controlled in the tank with the use of a PH controller.
  5. Liquid coagulant is injected into the tank via a chemical pump to assist with coagulating the remaining suspended solids to aid in settling.
  6. The water in the first 600 gallon tank will then gravity flow into the second 600 gallon tank, then to the third 600 gallon tank, in which both tanks will repeat the same process as in the first tank.
  7. The treated water from the third 600 gallon tank will then gravity flow into a final 205 gallon processed water tank, which is then transferred back to the pressure washer for reuse via a transfer pump.
  8. All three 600 gallon cone-bottom tanks are equipped with drain lines at the bottom of the tanks, which are tied together in a common drain line that will be run back to the original catch basin; this will give the user the ability to periodically dump any settled solids in both tanks and send them back to the catch basin.
  9. Also, the drain line back to the catch basin is setup to circulate water in the system when the user is not doing any washing in order to ensure that the water in the system continues to circulate; minimal circulation of the system will ensure extended life of the microbes and maintain system efficiency.
  10. Depending on volume of washing by the customer, as well as the amount of suspended solids, the entire system will periodically require the use of a vacuum truck to completely evacuate the system and dispose of the water and solids.  The system is then refilled and begins the process again with fresh water until the time comes for another cleanout.