CONTROL METHOD FOR METHANE FERMENTATION TANK AND CONTROL UNIT THEREFOR

摘要

PROBLEM TO BE SOLVED: To accurately measure the concentration of organic acids in organic waste or organic wastewater in a methane fermentation tank. SOLUTION: The method for controlling the methane fermentation tank by measuring the amount of organic acids in separated water obtained by removing a solid from organic waste or organic wastewater in the methane fermentation tank is disclosed. The method also comprises a process for moving the separated water to a CO2 dissolving tank 31 and using CO2 in the dissolving tank 31 to stirr the separated water, a process for transferring organic acids and dissolved CO2 to a diffusion tank 35 from the dissolving tank 31 and using sulfuric acid in the diffusion tank 35 to stirr the organic acids and dissolved CO2 to measure diffused CO2 from the diffusion tank 35 by a flowmeter 38, a process for moving organic acids to a diffusion tank 40 from the diffusion tank 35 and using NaOH in the diffusion tank 40 to stirr organic acids and measuring diffused NH3 from the diffusion tank 40 by a sensor and a process for controlling one or more of the charging amount of the organic waste or organic wastewater into the methane fermentation tank, the additional amount of nuturients to the methane fermentation tank and the concentration of NH3 in the methane fermentation tank on the basis of measured CO2 and diffused NH3 .