Method for operating separation membrane, separation membrane device, and program for determining operating conditions of separation membrane

A separation membrane device for filtrating a water-to-be-filtrated to obtain a filtrate, the separation membrane device comprising:

• an initial value acquisition unit configured to acquire an initial value of an amount of constituent components of a liquid-to-be-filtrated accumulated in a separation membrane;
• a data acquisition unit configured to acquire time-series change data of properties of the constituent components of the liquid-to-be-filtrated, time-series change data of the amount of the constituent components, and data indicating a time-series change in an operating condition of the separation membrane;
• a calculation unit configured to calculate an amount of the constituent components of the liquid-to-be-filtrated accumulated on a surface and in pores of the separation membrane after the initial value is set;
• a unit configured to calculate a restoration degree of an accumulated amount of the constituent components or membrane filtration resistance in chemical liquid cleaning based on a calculation result of the accumulated amount;
• and
• a chemical liquid cleaning condition determination unit configured to determine a chemical liquid cleaning condition based on a result obtained by the calculation unit, wherein the chemical liquid cleaning is automatically performed based on the chemical liquid cleaning condition determined by the chemical liquid cleaning condition determination unit.

A non-transitory computer-readable recording medium storing aA program for determining operating conditions of a separation membrane so as to determine a chemical liquid cleaning condition for the separation membrane to filtrate a water-to-be-filtrated to obtain a filtrate, the program causing a computer to execute:

• a step of acquiring an initial value of an amount of constituent components in a liquid-to-be-filtrated accumulated in the separation membrane;
• a step of acquiring data indicating a time-series change in properties of the constituent components in the liquid-to-be-filtrated and an amount of the constituent components and data indicating a time-series change in an operating condition of the separation membrane after the initial value is set;
• a step of integrating and calculating an amount of the constituent components in the liquid-to-be-filtrated accumulated on a surface and in pores of the separation membrane after the initial value is set,
• a step of calculating a restoration degree of an accumulated amount of the constituent components or membrane filtration resistance in chemical liquid cleaning based on a calculation result of the accumulated amount, and
• a step of determining the chemical liquid cleaning condition based on the calculation result.