The invention relates to an instrument used for environmental
science research, and specifically relates to a
microorganism BOD measuring
system for continuous
oxygen supply capable of providing accurate
temperature control. The
system has the working principle that under the conditions of constant temperature and normal pressure, biological degradation is carried out on microorganisms in a reaction
bottle, O2 is consumed for generating CO2, after CO2 is absorbed by an absorbent, the pressure inside the reaction
bottle is reduced,
pressure difference is generated, and a circuit inside a U-shaped
pipe is communicated. The current inside the U-shaped
pipe is too small, and the starting of a
direct current power supply module cannot be triggered. Therefore, an electrical
signal is amplified to control the starting of the
direct current power supply
assembly through a micro
signal amplifier, a CuSO4 solution inside an
electrolysis bottle is electrolyzed to generate O2, and simultaneously the quantity of
electric charge of
electrolysis is recorded by a
coulombmeter; and when O2 is supplemented into the reaction bottle, the
pressure difference inside the pressure gage with the U-shaped
pipe disappears, the circuit is disconnected, the
direct current power supply
assembly is turned off, the
electrolysis bottle stops electrolysis, and the
coulombmeter stops recording. Due to the fact that the
oxygen consumption is in direct proportion to the quantity of
electric charge of electrolysis, the electric quantity consumed by the electrolysis bottle is accurately monitored by the
coulombmeter, and the BOD value is converted through the electric quantity.