Is the dung suction car a duty-free car?

The dung suction car is not a duty-free car.

The main working principle of dung suction car:

The vacuum pump operates to absorb pollutants and exhaust the air in the tank at the same time, and the pollutants are pressed into the tank by air pressure; When discharging pollutants, the vacuum pump is operated to increase the air pressure in the tank to discharge pollutants in the tank. Because the vacuum pump completely sucks pollutants, it can only pump light pollutants, and is generally used in farms, toilets and other facilities.

Function description of dung suction vehicle: vacuum dung suction vehicle configuration: the special part consists of power take-off, transmission shaft, vacuum dung suction pump, water-gas separator, oil-gas separator, multi-way reversing valve, suspender, dung tank, dung discharge valve, dung suction gun, clear water tank, dung observation window, vacuum pressure gauge and pipe network system. This product is used to absorb feces, sewage, sludge slurry and liquid mixed with fine suspended impurities. It has the characteristics of high suction efficiency, self-suction and self-discharge, direct irrigation, etc., and is widely used in sanitation, municipal administration, agriculture, chemical industry, factories and mines, and property communities in large, medium and small towns. The vacuum suction pump can suck and discharge feces by itself.