Air purification equipment allows astronauts to breathe freely

The clean air in space is very important to the life and health of astronauts. Generally speaking, the space in the aircraft cabin is small and the airtightness is good, and the astronauts and the non-metallic materials and instruments in the cabin are volatilizing various harmful gases at any time. Effective measures are taken to strictly control harmful gases in the cabin to ensure air quality.

Dong Wenping, director of the Chinese Astronaut Research and Training, Environmental Control and Life Protection Research Office, said that the astronauts of the Shenjiu mission stayed in the Tiangong-1 (Weibo) Shenzhou-9 complex for ten days, and the complex space was only 60 To purify the air in the cabin, three problems need to be solved. One is to purify the carbon dioxide produced by the astronauts' breathing. Carbon dioxide is responsible for the purification of the cabin atmosphere, and if the concentration is too high, the health of the astronauts will be endangered. It is generally required that the partial pressure of carbon dioxide in the cabin should not be greater than 1 kPa, and an alarm should be issued when it reaches 2 kPa. The second is trace amounts of harmful gases, which are volatilized from non-metallic materials in the cabin under airtight conditions. The longer the cabin is sealed, the higher the concentration of harmful gases. The third is the particulate matter or microorganisms contained in the atmosphere itself.

Dong Wenping said that at present, there are two main ways to solve these three harmful gases: one is to purify the fan. About 20 days before the launch of Shenjiu, Tiangong-1 has started the purification fan to purify the air in the cabin. . The purification fan introduces the atmosphere in the cabin into the purification tank, and after chemical decomposition and absorption, the clean air flows back into the cabin again. The purification fan is the key to the normal operation of the air purification device, and its energy consumption is low, only equivalent to the energy consumption of an ordinary lighting lamp. In order to improve the reliability of the air purification device, a dual-machine solution is adopted. Once the main fan fails, it can automatically switch to the working state of the auxiliary fan to ensure that the purification fan is always in working state. Another purification method is to set activated carbon and a small amount of room temperature catalyst in the purification tank to form a combined purification device to absorb and absorb trace harmful gases in the aircraft cabin, which is more suitable for spacecraft for short-term flight.

Dong Wenping said that the air quality in the combination of the spacecraft and the target aircraft has specific limited indicators, and the inhalable particulate matter per square meter also needs to be controlled within a certain range, which is equivalent to the standard of a 100,000-level purified space. The final assembly plant for ground aircraft.