Recycling of dichloromethane gas and treatment to meet regulatory standards

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Sources of VOC emissions: Production units: reaction vessels, distillation/evaporation units, drying equipment, centrifugal filtration systems, storage tanks, wastewater tanks, etc. Traditional VOC treatment processes: condensation (light cryogenic, deep cryogenic), adsorption (activated carbon/carbon fiber/resin), absorption, biological methods (microbial degradation), photocatalytic oxidation, low-temperature plasma, RTO, etc. Disadvantages of traditional VOC treatment processes: deep cryogenic methods can lead to icing; activated carbon generates solid waste; adsorption and desorption processes produce large amounts of wastewater; the removal efficiency is low; high concentrations can cause saturation; halogen-containing exhaust gases can corrode RTO units and lead to the formation of dioxins, posing a threat to the environment. The fundamental reason why traditional processes cannot meet the requirements is poor process suitability, along with a lack of transition treatment processes from high concentrations to low concentrations. The three-stage overlapping VOCs waste gas treatment process combines compression condensation, membrane technology, and adsorption; in the range of medium-concentration VOCs, it uses membrane units to facilitate the transition from high-concentration areas to lower-concentration areas, thereby ensuring that the VOCs emissions meet regulatory standards. Waste gas flow rate of dichloromethane: 50–10,000 m3/h; concentration >5%. Waste gas parameters: Inlet concentration range (ppm), outlet concentration of the compression condensation membrane device (ppm), outlet concentration of the adsorption device (mg/m3). For dichloromethane (DCM): Inlet concentration >50,000 ppm; outlet concentration 800–5,000 ppm; outlet concentration <20 mg/m3. Engineering examples: In the pharmaceutical industry, a dichloromethane waste gas treatment system with a flow rate of 200 Nm3/h is used; the inlet concentration is 24%, while the outlet concentration is <20 mg/m3. In the chemical industry, there are recovery systems for propylene oxide with a flow rate of 300 m3/h and for dichloropropane with a flow rate of 300 m3/h; the inlet concentration of propylene oxide is 58%, with an outlet concentration of <1 mg/m3, while the inlet concentration of dichloropropane is 8.7%, with an outlet concentration of <50 mg/m3. Please feel free to contact us by phone if you have any inquiries. Mr. Li 15850669279