Gas without odor or insufficient odor must be treated before entering the gas transmission and distribution system. The automatic gas odor adding device produced by our company (referred to as the odor adding device, as shown in Fig.1) adopts the micro mixed signal processor to automatically detect calculate and control, and the addition ofmedicamentis accurate and adjustable.With manual and automatic switching function, can achieve flexible deodorization. Manual deodorization mode, can directly set the output dosing frequency. Automatic odor adding mode,mainly through the micro diaphragm metering pump willadd odor agent (tetrahydrothiophene THT)from theodor storage tank, and pump into the gas transmission and distribution pipe to achieve odor.In order to achieve the purpose of accurate deodorization,there areflow detection, signal acquisition and transmission in the transmission and distribution main pipeand the signal is fed back to the computer. According to the set amount of gas flow per cubic meterthe computer controls the metering pump to adjust the amount of odor, to ensure the odor effect of natural gas,and to effectively ensure the safety of users.