TH17637A - Methods and tools for controlling wastewater treatment using biological methods. - Google Patents

Abstract

Methods and tools (1) for biological control of wastewater treatment in which wastewater is fed into a filter unit for the growth of microorganisms in an airless environment (2) which has an exhaust pipe (5) dissolved oxygen is fed into the filter unit and the rate of oxygen consumption in the filter unit is measured by comparing the rate of oxygen flow into the filter unit (2) with the rate of oxygen flow out of the filter unit through the exhaust pipe (5) adjust the rate of wastewater feed into the filter unit to maintain the oxygen supply rate as determined beforehand, which is the control of the quality of the discharge water. The optimal oxygen consumption rate to achieve the desired discharge water quality is determined by experiment for each system and type of wastewater to be treated.

Claims (18)

1. The biological wastewater treatment method consists of the following steps: Feed wastewater into an aerobic filtration unit with an aeration pipe. Add oxygen to the filtration unit. Measure the oxygen consumption in the filtration unit by comparing the oxygen flow rate into the unit with the oxygen flow rate out of the unit through the aeration pipe. Adjust the wastewater flow rate to maintain the set oxygen consumption rate. 2. The method under claim 1 involves determining the oxygen consumption rate by measuring the gas flow rate out of the biological filter unit and calculating the mole fraction of oxygen in the filter unit. These values are then subtracted from the measured dissolved oxygen feed rate into the filter unit. 3. A method under claim 1 or 2, which includes additional steps to maintain the filtration unit at a pressure slightly higher than atmospheric pressure to prevent the diffusion of air back into the filtration unit. 4. The method stipulated in any one of the preceding claims involves feeding wastewater into the unit and allowing the treated water to flow out of the filtration unit into a settling pond. 5. The method under claim 4, which involves draining the treated wastewater and using a first holding pond for clarification. 6. The method under claim 5 involves mixing a portion of the treated wastewater in the holding pond with the wastewater fed into the filtration unit for recirculation. Seven methods under claim 6 adjust the recirculation rate until the oxygen consumption rate in the filter unit reaches the desired, specified point. 8. Equipment for controlling biological wastewater treatment: This equipment consists of: a filter unit to support the growth of microorganisms in an airtight environment, with a liquid inlet pipe, a liquid outlet pipe, and an exhaust air outlet pipe; an oxygen gas feeder that supplies oxygen to the filter unit and controls the oxygen flow rate through the exhaust air outlet pipe; a feeder that responds to signals to release wastewater at a predetermined flow rate to the filter unit; and a controller that compares the oxygen flow rates into the filter unit and out of the exhaust gas outlet pipe to determine the oxygen utilization rate in the filter unit and sends control signals to adjust the feeder to maintain the predetermined oxygen utilization rate. 9. The device pursuant to claim paragraph 8, in which the filtration unit has a pressure regulator that maintains an internal pressure higher than atmospheric pressure to prevent the diffusion of air back into the filtration unit. 10. An instrument as specified in claim 8 or 9, which discharges liquid into the upper part of the filtration unit and has a liquid reservoir that leads to the liquid outlet pipe of the filtration unit. 11. The device under claim 10, which has a water clarification layer connected to a pipe for water flowing out of the manhole. 12. Equipment as provided for in Claim 10 or 11, which includes pipes that divide a portion of the treated water in the holding pond and the wastewater fed into the filter unit. 13. Any instrument under claims 8 through 12, in which the settling tank has a liquid reservoir in which water flows from the outlet, which is connected to the base of the filtration unit by gravity. 14. Any device under claims 8 through 13 where the holding pond also has a shared pond to receive wastewater recirculated directly from the filtration unit or through the liquid treatment pond of claim 13. 15. Equipment as per claim 14, which feeds water to a filtration unit designed to separate recirculating wastewater from untreated wastewater from the common pond. 16. Any device under claims 13 through 15 which also has a water purification device or other wastewater discharge device connected to a liquid clearing well and intended to receive a portion of the liquid flowing out of that well. 17. Methods of biological wastewater treatment, which are mostly similar to those described using the provided illustrations. 18. Instruments for controlling biological wastewater treatment which are largely identical to those described by reference to the provided drawings. (18 claims, 3 pages, 1 drawing)