Fine chemical high concentration VOCs organic solvent recovery equipment, the strength of the production enterprise Luoyang Wo Hong Petrochemical.

In the process of fine chemical production, the processes such as pressure relief of the distillation tower, devolatilization of the reaction kettle, solvent feeding, material replacement, etc. will continue to produce high concentration VOCs organic solvent waste gas. The proportion of organic solvent in the waste gas is high, and the components include ketones, esters, alcohols, aromatic hydrocarbons, halogenated alkanes and other substances. Production operations are mostly intermittent batch mode, exhaust gas conditions fluctuate violently, concentration shocks will occur in a short period of time, and the airflow is mixed with material droplets and saturated water vapor. Some halogenated solvents will hydrolyze after contacting with water vapor to generate acidic substances, which will cause corrosion to the equipment. The high-concentration organic medium itself is flammable and explosive. Once leakage occurs, it will bring greater safety hazards. The corrosion resistance, safety protection level and working condition tolerance of the recycling equipment are all highly required. Traditional governance methods have many limitations in the face of high-concentration exhaust gas scenarios, and it is difficult to achieve both exhaust emission standards and solvent resource utilization.

The incineration process can complete tail gas purification, but a large number of valuable solvents are directly incinerated under high concentration conditions, resulting in prominent resource loss. After high-temperature combustion of halogen-containing media, corrosive products will be generated and subsequent pipeline facilities will be corroded. Supporting tail gas treatment devices need to be added, and equipment investment and daily operation and maintenance costs are at a high level.activated charcoalUnder the condition of high concentration of exhaust gas, the adsorption material will quickly reach saturation, the phenomenon of adsorption penetration is frequent, frequent downtime to replace the adsorption material, the amount of hazardous waste generation is huge, enterprises need to bear high consumables and hazardous waste disposal expenses. The simple cryogenic condensation process relies on low-temperature conditions to liquefy the solvent. Although a part of the solvent can be recovered in a high-concentration environment, due to the partial pressure of organic vapor, considerable organic components still remain in the tail gas, which cannot be fully recovered and the overall resource utilization effect is limited.

The compression condensation film coupling process adopts a pure physical treatment method, and the whole process does not involve combustion reaction, which is very suitable for the treatment scenario of high concentration VOCs waste gas in fine chemical industry. The waste gas enters the pretreatment unit first, and the liquid mist, fine solid impurities and free moisture carried by the airflow are removed by means of a multi-stage filtering and defoaming structure to prevent impurities from entering the back-end core unit and causing blockage and damage. After the purification, the exhaust gas enters the compression unit, increases the partial pressure of organic vapor, improves the solvent liquefaction conditions, and then sends it to the multi-stage gradient condensation module, and performs gradient cooling according to the difference of boiling points of different solvents, so that most organic solvents can be liquefied and separated, and the preliminary recovery work is completed.

After the condensation treatment, the remaining tail gas still contains a certain amount of organic solvent and will be sent to the organic membrane separation unit. Relying on the selective permeability characteristics of the membrane material for organic solvents and air, the enrichment and separation of solvent components are completed, the tail gas after treatment is discharged outward, and the high-concentration organic gas stream formed by enrichment is returned to the compressor inlet position, and enters the system again to participate in the circulation treatment. The closed-loop circulation mode maximizes the solvent recovery efficiency. The recovered organic solvent can be put back into the production link after being precipitated, filtered and tested to meet the use standards. The solvent resources lost in the waste gas can be recycled, the generation amount of hazardous waste can be reduced from the source, and the cost of raw material procurement and hazardous waste disposal can be reduced.

In view of the special working conditions of high concentration waste gas of fine chemical industry, the equipment configuration design must conform to the actual working conditions on site. Corrosion resistant materials are selected for pipelines, valves and heat exchange components in contact with exhaust gas to resist corrosion damage caused by acidic medium and maintain long-term stable operation of the equipment. The equipment is equipped with complete overpressure, overtemperature, medium leakage monitoring and automatic interlocking protection mechanism to avoid safety risks under high concentration flammable and explosive conditions. The automatic control system is equipped with a frequency conversion adjustment mechanism, which can respond to drastic changes in exhaust gas volume and concentration in real time, automatically adjust the operating load of the equipment, bear the concentration impact in the production process, avoid overload operation or invalid idling of the equipment, and control the energy consumption level. The pre-pretreatment system intercepts all kinds of impurity droplets in stages, forms effective protection for precision parts such as heat exchangers and membrane modules, and prolongs the service life of the equipment. Process design needs to collect on-site measured exhaust gas air volume, component composition, concentration range, water content and impurity data to carry out customized accounting, can not directly apply the general model, in order to ensure the stability of exhaust gas treatment standards, and effectively achieve the goal of organic solvent resource recovery and cost reduction.