Organic tail gas condensation membrane recovery unit, three-stage condensation plus membrane separation

The organic waste gas recovery unit employing membrane-based condensation integrates three-stage condensation with membrane separation in a cascaded manner, forming a comprehensive recovery and treatment system. The device is mainly aimed at the scene of organic tail gas with medium and high concentration and recovery value, and realizes the unification of organic matter recovery and tail gas standard emission through step-by-step cooling liquefaction and membrane separation enrichment cycle.

Three-stage condensation: graded cooling, stepwise liquefaction

The condensing unit is designed according to the logic of gradient cooling. The first-stage condensation cools the tail gas to 3~5 ℃, mainly removing high-boiling components and water vapor to prevent frosting or blockage in the subsequent low-temperature section; the second-stage condensation is reduced to -20 ~-30 ℃, corresponding to the boiling point range of the medium-boiling solvent, and the main body is recovered; the third-stage condensation is further reduced to -65 ~-75 ℃, and the low-boiling components are deeply trapped. This graded cooling method is more controllable than directly pulling the temperature to the lowest, and the energy consumption is more controllable.

Membrane separation: enrichment cycle, closed loop recovery

The condensed tail gas still contains a small amount of organic compounds that have not been liquefied; this portion of the gas enters the membrane separation unit. Taking advantage of the difference in the permeation rate between organic molecules and air molecules in the membrane material, organic matter preferentially permeates through the membrane layer to form concentrated gas, which is sent back to the compressor inlet to re-enter the condensation process for circulation treatment. Membrane separation solves the problem of condensation "not clean" and makes the system form a closed recovery loop.

Scope of application and characteristics

The device is suitable for organic tail gas with a concentration of more than 1000 mg/m and a solvent with recovery value. The process is driven by electricity, does not involve combustion, and does not produce hazardous waste. The combined design of three-stage condensation and membrane separation provides a balance between recovery efficiency and operating energy consumption. Before selecting equipment, it is recommended to first conduct a process condition assessment and match the equipment specifications based on concentration, composition, and airflow rate.