LuoyangWohong PetrochemicalThe three-inch organic gas vapor membrane independently developed and produced by Equipment Co., Ltd. belongs to the roll-up organic vapor separation membrane element and is the core separation unit of the VOCs solvent recovery unit in Wohong. The product adopts the optimized silicone rubber composite membrane material, and realizes the selective separation of organic vapor and carrier gas based on the dissolution and diffusion mechanism. The membrane element is a three-inch standard outer diameter specification, compact in structure, suitable for small and medium-sized membrane separation and recovery units in Wohong, supports modular series or parallel combination, can flexibly adjust the number of membrane modules according to the exhaust gas treatment air volume, and is suitable for exhaust gas resource treatment requirements under different working conditions such as fine chemical industry, pharmaceutical production, coating processing, oil and gas recovery, etc.

After the mixed tail gas enters the feed side of Wohong 3-inch organic gas vapor membrane, driven by the partial pressure difference between the two sides of the membrane, the organic solvent vapor in the tail gas preferentially dissolves into the membrane functional layer, then penetrates the membrane body through diffusion, enriches at the permeation side to form high-concentration organic vapor, which is subsequently sent to the condensation unit for liquefaction and recovery; non-condensable carrier gas such as air and nitrogen is difficult to pass through the membrane layer, which is left at the feed side and discharged as leach, the treated tail gas can meet the environmental emission targets. Wo Hong's three-inch membrane adopts a standardized shell structure, with simple component disassembly and replacement process, reducing the difficulty of on-site operation and maintenance, and having good adaptability in small and medium-sized air volume tail gas treatment scenarios.

Wo Hong has specially optimized the membrane material formula, and the finished product has good solvent swelling resistance, can withstand the long-term erosion of ketones, esters, alcohols, halogenated hydrocarbons and other organic solvent vapors, and maintains stable permeation flux and separation selectivity under fluctuating exhaust gas concentration and temperature conditions. Compared with large-size membrane elements, Wohong three-inch organic gas vapor membrane is more suitable for treating small and medium-sized flow tail gas. Membrane modules can be gradually added during the phased construction of the project, and the initial investment can be controlled. It is not necessary to purchase a full set of large-scale equipment at one time, thus improving the economy of the project. The membrane element can be combined with the condensation process to form the mature condensation membrane coupling process of Wohong, first through condensation to recover most of the high concentration solvent, the remaining low concentration of tail gas into the membrane element for further enrichment treatment, greatly improve the total recovery rate of solvent, reduce VOCs discharge.

There are no moving parts during the operation of the whole membrane unit, the operating noise is low, there is no need to add drugs frequently, and the daily maintenance workload is small. Wohong three-inch organic gas vapor film matching system has a fast start-up speed and can run synchronously with the start and stop of the production line, which is suitable for intermittent production conditions. In view of the intermittent exhaust gas generated by the production of pharmaceutical chemical industry and fine chemical industry, the three-inch film of Wohong can flexibly match the change of exhaust gas load with modular design, and control the energy consumption level while ensuring stable recovery efficiency. The standardized interface design of membrane elements is compatible with the whole series of skid-mounted membrane separation and recovery devices in Wohong, which is convenient to integrate into the existing tail gas treatment system for technical upgrading, without large-scale modification of the original pipeline layout, thus shortening the construction period of the project.

Organic vapor recovery is a resource‑based treatment solution. The recovered organic solvents, after simple purification, can be reintroduced into the production process for reuse, thereby reducing VOC emissions while generating value from material recovery. The Wohong 3-inch organic gas vapor membrane, as the company’s flagship compact standard membrane module, fills the gap in membrane separation equipment selection for low-flow applications and is widely used in tailgas treatment projects at small and medium-sized plants. All Wohong membrane elements undergo rigorous leak‑testing prior to leaving the factory, ensuring consistent separation performance for each individual element. When multiple elements are operated in combination, the entire membrane system delivers stable separation performance, and the failure of a single element will not cause the entire system to shut down. During operation and maintenance, damaged elements can be replaced individually, thereby reducing long‑term O&M costs. During the actual project design phase, the Wohong technical team integrates parameters such as exhaust gas composition, temperature, pressure, and flow rate to determine the number of membrane modules required. They also incorporate a pre‑filtration pretreatment unit to remove liquid droplets and particulate impurities from the exhaust gas, preventing contaminants from adhering to the membrane surface, thereby reducing membrane fouling, extending the service life of the membrane elements, and ensuring the long‑term stable operation of the entire VOCs recovery system.Leveraging the R&D platform of the Henan Province Oil and Gas Recovery Engineering Technology Research Center, WoHong continuously iterates on membrane material formulations and membrane module designs, consistently optimizing product performance to suit the exhaust gas conditions of various industries. The company provides customers with integrated supply and technical services, including membrane modules, membrane assemblies, and complete recovery systems.