JP2019000781A5 - - Google Patents

Claims (16)

A biological treatment tank that biologically treats organic wastewater under aerobic conditions and generates sludge-containing treated water containing activated sludge;
A solid-liquid separation unit for separating sludge-containing treated water generated in the biological treatment tank into concentrated sludge and treated water,
Sludge-containing treated water generated in the biological treatment tank, or concentrated sludge separated in the solid-liquid separation unit is drawn out at a predetermined sludge withdrawal flow rate to perform ozone treatment, and the treated sludge-containing treated water or concentrated sludge is treated. An ozone reaction unit returned to the biological treatment tank,
An ozone generator that generates ozone and supplies the ozone to the ozone reaction unit;
Sludge concentration measuring means for measuring the sludge concentration of the mixture containing the sludge-containing treated water in the biological treatment tank,
Water quality measuring means for measuring the quality of each of the mixed solution, the treated water, and the effluent that has disinfected the treated water,
The sludge withdrawal flow rate is determined based on the sludge concentration of the mixed solution, and the amount of ozone used in the ozone treatment is determined based on the product of the sludge concentration and the sludge withdrawal flow rate of the mixed solution. A wastewater treatment system comprising a calculation and control device for adjusting the sludge withdrawal flow rate and the ozone usage based on at least one of the water quality data. The sludge concentration measuring means, the mixture of the biological treatment tank at a timing immediately before withdrawing the sludge-containing treated water from the biological treatment tank after 攪拌, characterized in that the measurement of the sludge concentration in the mixed solution The wastewater treatment system according to claim 1.   The arithmetic and control unit determines the amount of ozone to be added based on water quality data of the mixed solution with respect to the amount of ozone used based on the product of the sludge concentration of the mixed solution and the sludge withdrawal flow rate. The wastewater treatment system according to claim 1 or 2.   4. An ozone concentrator for concentrating ozone generated by the ozone generator, wherein the ozone concentrator supplies the concentrated ozone to the ozone reaction unit. Wastewater treatment system according to the paragraph.   The said calculation and control apparatus determines the pressure of the ozone adsorption tower of the said ozone concentrator, and the flow rate of the ozone injected into the said ozone reaction part based on the determined ozone usage. Wastewater treatment system as described.   A pipe for circulating sludge-containing treated water drawn from the biological treatment tank or concentrated sludge drawn from the solid-liquid separation section; and The wastewater treatment system according to any one of claims 1 to 5, further comprising an ejector for injecting water.   The ozone reaction unit has a plurality of ejectors having different nozzle diameters, and the calculation and control device determines an ejector to be used from the plurality of ejectors based on the determined sludge withdrawal flow rate and the ozone usage amount. The wastewater treatment system according to claim 6, wherein:   Based on the determined sludge withdrawal flow rate and the amount of ozone used, the arithmetic and control unit controls the flow rate of the sludge-containing treated water or the concentrated sludge circulating through the pipe so that the gas-liquid flow rate ratio in the ejector becomes a minimum value. The wastewater treatment system according to claim 6, wherein a concentration and a flow rate of the ozone injected into the ejector are controlled.   A data storage device for storing data used for the calculation by the calculation and control device, wherein the data storage device is configured to measure at least the sludge concentration measuring means, the water quality measuring means, the sludge withdrawal flow rate, and the sludge flow meter. The wastewater treatment system according to any one of claims 1 to 8, wherein data including a measurement value of an ozone gas flowmeter that measures a flow rate of ozone injected into the ozone reaction unit is stored. .   The wastewater treatment system according to claim 9, wherein the data stored in the data storage device is collected online.   The wastewater treatment system according to claim 9, wherein a part or all of the data stored in the data storage device is input by an operator.   The arithmetic and control unit obtains a sludge treatment ratio and a convergence value of the ozone injection amount based on the data obtained from the data storage device, and automatically sets a parameter that satisfies the obtained sludge treatment ratio and the convergence value of the ozone injection amount. The wastewater treatment system according to any one of claims 9 to 11, wherein the calculation is performed.   An arithmetic data control unit for storing experimental data including correlation data between sludge concentration and ozone usage or sludge volume reduction effect, and experiment data including correlation data between water quality and ozone usage or sludge volume reduction effect; 10. The sludge concentration and the water quality data obtained from the data storage device, the sludge extraction flow rate and the ozone usage amount are adjusted with reference to the experiment data stored in the experiment data input device. The wastewater treatment system according to any one of claims 1 to 12.   14. The arithmetic and control unit according to claim 1, wherein the sludge withdrawal flow rate and the ozone usage amount are adjusted so that the water quality data of the discharge water satisfies a preset water quality standard of the discharge water. Wastewater treatment system according to any one of the preceding claims.   The said calculation and control apparatus determines the time and space | interval which inject | pours ozone into the said ozone reaction part based on the determined ozone consumption, The Claims 1-14 characterized by the above-mentioned. Wastewater treatment system. Biological treatment of organic wastewater under aerobic conditions to produce sludge-containing treated water containing activated sludge;
A solid-liquid separation step of separating the sludge-containing treated water generated in the biological treatment step into concentrated sludge and treated water,
A reforming step of performing ozone treatment by extracting sludge-containing treated water generated in the biological treatment step, or concentrated sludge separated in the solid-liquid separation step at a predetermined sludge extraction flow rate,
The sludge withdrawal flow rate is determined based on the sludge concentration of the mixture containing the sludge-containing treated water in the biological treatment step, and the amount of ozone used in the ozone treatment is determined based on the product of the sludge concentration and the sludge withdrawal flow rate of the mixture. And a wastewater treatment method characterized by adjusting the sludge withdrawal flow rate and the ozone usage based on at least one of the water quality data of the mixed solution, the treated water, and the effluent discharged from the treated water.