Application of compression condensation membrane separation in chemical plants: waste gas recovery in storage tank area

Application of compression condensation membrane separation in chemical plants: waste gas recovery in storage tank area

Chemical plant storage tank area is the key area of VOCs unorganized emissions. Breathing valve due to the temperature difference between day and night and frequent opening and closing of loading and unloading operations, the exhaust gas discharged has the characteristics of large concentration fluctuations, high oxygen content, discontinuous emission and other characteristics of mixed gas, which contains benzene series, alkanes, alcohols and other organic components are not only pollutants, but also product resources with recycling value.

Compared to organized emission sources, the challenge of waste gas treatment in tank farms is that the fugitive concentration is variable and the system must operate safely in the presence of oxygen. The single condensation process is difficult to adapt to this fluctuating condition economically, and the simple adsorption technology is faced with the problem of frequent replacement of consumables. The combined process of compression-condensation membrane separation has proved to be an effective solution to such difficulties.

The process adopts the coupling process of "compression shallow cooling-membrane separation-adsorption. First, the tail gas is sent to the condensing unit through compressor pressurization to recover a large amount of hydrocarbons, and the pretreated mixture enters the membrane separation module. Using the characteristics of different permeation rates of organic vapor and air in the membrane material, hydrocarbons are preferentially enriched through the membrane to form a high-concentration organic gas stream and circulate back to the front-end system, while nitrogen and oxygen in the air are trapped and discharged. For occasions with strict emission standards, the end of the system.activated charcoalThe adsorption unit serves as a gatekeeper to ensure that the emission concentration of non-methane total hydrocarbons in the purified gas is ≤ 120 mg/m.

The comprehensive benefit of the scheme is remarkable in practical application.

LuoyangWohong PetrochemicalEquipment Co., Ltd. can provide customized skid-mounted complete sets of equipment in storage tank area, relying on "compression condensation membrane separation" technology to support a variety of working conditions adaptation. The company's official website www.wohongshihua.com, address: W2-1, Dongda Science and Technology Industrial Park, Luoxin Industrial Cluster, Xin 'an County, Luoyang City.