Recovery and reuse technology of organic waste gas with low VOCs concentration

In the current era of increasing environmental protection and people's attention, VOCs waste gas has begun to receive more and more attention from everyone, so VOCS recycling has received more and more attention from enterprises. , There are different treatment methods on the market, and the advantages of recycling and treatment technology with large emissions and low VOC concentration. 1. High-concentration VOC recovery technology in gas The light oil product loading process and the large and small breathing operations of the tank farm discharge high-concentration oil and gas, of which the concentration of VOC can reach more than 1000g/m3, and the general loading discharges oil and gas, and the average non-methane total Hydrocarbon concentrations are in the hundreds of grams per cubic meter. Non-methane total hydrocarbon concentration required for emission limits≤20g/m3 and 25g/m3, using mechanical refrigeration for low temperature condensation→Filter capture processing method. The first-stage heat exchange adopts the cold energy recycling technology; the two-stage mechanical refrigeration method is adopted to establish a low temperature environment not higher than -95 °C, and the hydrocarbons in the oil and gas are condensed and recovered; Filtration and capture treatment to improve the recovery rate of oil and gas. 2. Low-concentration VOC recovery technology in the gas The VOC concentration is low, but the total amount of VOC emissions from various process waste gases with large gas emissions is considerable. For example, the VOC emission concentration is 300mg/m3, the gas emission is 40000m3/h, and the VOC emission per hour is about 12kg. The annual production unit operation time is calculated as 8,000 hours, and the VOC emission is about 96t. This is the production emission of two latex gloves. The actual situation of D60, D70 solvent oil does not include almost the same amount of DOP mist emission. The VOC emission concentration limit, the national standard and the petrochemical industry standard is 120mg/m3, and the local standards in different places are 100mg/m3 and 80mg/m3. There are two situations for waste gas with low VOC concentration but large gas emission. One is that the emission concentration exceeds the standard, and the other is that the emission concentration meets the standard. For the waste gas that exceeds the standard, it should be treated. It has large emissions and has recycling value, which can significantly reduce production costs. Double adsorbers are used to adsorb and desorb alternately, adsorb and concentrate VOC, and the exhaust gas is discharged up to the standard. For characteristic pollutants with low emission limit requirements, the exhaust gas can be treated by oxidation method. Vacuum desorption is adopted, the desorbed rich gas is condensed and recovered at low temperature, and the unrecovered VOC is sent to the adsorber for adsorption treatment.