Tester for testing CH4, CO2 and biogas slurry pH value meanwhile

The utility model relates to a tester which can simultaneously detect CH4 and CO2 in marsh gas and the pH value of biogas slurry, in particular to a special testing instrument which can simultaneously detect CH4 and CO2 in marsh gas components and the pH value of biogas slurry. The tester is characterized in that, an instrument measurement and control system are respectively connected with a power supply, a marsh gas component sensor, a pH sensor, an air pump, a display interface and a keyboard interface; an air inlet is connected with the left end of the marsh gas component sensor by passing a dust filter and the air pump; the right end of the marsh gas component sensor is communicated with an air outlet; the body of the instrument measurement and control system is an embedded single chip system. The tester has the advantages that the marsh gas component sensor and the pH sensor are simultaneously utilized in a single instrument, so one or both of the volume percentages of CH4 and CO2 in the mash gas components can be measured, and the pH value of biogas slurry can also be measured; the marsh gas component sensor and the pH sensor are integrated in a whole, so the total cost of instrument purchasing is reduced; the detection of marsh gas components and the pH of biogas slurry can be completed at the same time, and the detection is convenient and accurate.