| 摘要 |
<p>PURPOSE:To perform microbial reaction stable over a long period of time without excessively supplying a pH controller, by measuring the floating state of the microorganism in the solution of a microorganism reaction tank. CONSTITUTION:A practically measured pH value (p) measured by a PH meter 21 is inputted to a comparator circuit 32 and compared with a preset objective pH value p' and the deviation (p-p') thereof is inputted to a control circuit 33. The control circuit 33 regulates a caustic soda supply apparatus 12 to a reducing direction if the deviation is a positive side and regulates the same to an increase direction if a negative side. The practically measured value (s) of the concn. of a microorganism measured by a microorganism densitometer 22 is compared with a preset lower limit value (s') of microorganism concn. by a judge circuit 34 and, if the deviation (s-s') is negative side, an offering signal is inputted to a control circuit 33 so as to bring the supply amount of caustic soda to zero. By this offering control, operation control corresponding to a microorganism reaction state is enabled.</p> |
