How to recycle vinyl acetate waste gas? The main line consists of three steps: the ester containing tail gas from the tank breathing and production processes is first collected in a closed manner, and then most of the vapor is condensed and recovered through two-stage condensation. The condensate is then reused or disposed of separately after settling and layering. Its boiling point is about 73 ℃, and it evaporates significantly at room temperature. The sealing of the collection system directly determines the recovery effect, and the management and reuse conditions of the condensate are the focus of this process line.
The first is low boiling point and fast volatilization. The boiling point of about 73 ℃ means that the saturated vapor pressure is not low at room temperature, and unorganized emissions are formed in the breathing, loading and unloading, feeding, and cleaning processes of storage tanks. The emissions further increase during the high temperature period in summer.
The second is its lively chemical properties. As a polymer monomer, it is prone to self aggregation when stored for a long time or heated. The condensate in the recovery system should not be retained for a long time. The storage and transportation process should be arranged according to the characteristics of the material, and the retention time of the recovery device should be considered when selecting.
The third is flammable. The fan, electrical and anti-static grounding of the exhaust system are treated as flammable media, and the collection pipeline is kept conductive and grounded. The quick connectors and recovery valves at the loading and unloading ports are regularly inspected for sealing.
The collection branch pipe is led out from the breathing port of the storage tank and flows into the main pipe; The loading and unloading vehicle adopts a bottom loading refueling gas recovery joint; Partial fencing and directional ventilation should be added to open operation points such as feeding and cleaning. Verify the simultaneous use factor before merging multiple branches to avoid diluting concentration with high air volume and increasing the condensation load at the rear end; Maintain the slope of the pipeline and set a low point for drainage to prevent the accumulation of condensate and blockage of the road.
The mainstream configuration is two-stage condensation: the front stage pre cooling dehumidification reduces the exhaust gas temperature and releases the carried water vapor, reducing frosting and water carryover on the rear stage heat exchange surface; The secondary cryogenic system condenses and recovers most of the ester vapors. Use heat exchangers between two stages to recover cooling capacity and reduce operating energy consumption; The selection of materials for low-temperature pipelines and valves should be checked according to the compatibility of the medium, and insulation and anti condensation measures should be taken.
The setting of condensation temperature should be balanced between recovery rate and operating costs: the lower the temperature, the higher the recovery rate, but the energy consumption and frost risk increase synchronously. Generally, it is determined based on the characteristics of the medium and local emission limits, without making unfounded extreme low temperatures.
After initial dehydration through settling or coalescence separation, the condensate is reused for production ingredients or sent to the refining unit for processing according to its quality; The water phase is merged into the factory wastewater system for unified treatment. The differences in recovery between it and common ester solvents are shown in the following table:
| comparison dimension | Vinyl acetate | Common ester solvents |
|---|---|---|
| volatility | Boiling point is about 73 ℃, with significant volatilization at room temperature | By variety, the span is relatively large |
| Material Characteristics | Monomer properties are lively, avoid prolonged retention | Relatively stable in nature |
| Condensed liquid management | Timely turnover and control of dwell time within the system | Reuse after conventional separation |
| Recycling destination | Reuse ingredients or send to refining unit | Reuse after layered dehydration |
The condensate can be reused in the batching process after dehydration and quality verification. If the purity or moisture does not meet the requirements, it shall be sent to the refining unit for treatment and then reused, which shall be determined according to the measured quality.
Its boiling point is low and its volatilization at normal temperature is obvious. The open leakage of the collection port will allow a large amount of steam to escape directly without treatment. The condensation load at the back end is also increased due to the dilution of air volume. The tightness is the premise of the recovery effect.
No. The lower the temperature, the higher the recovery rate, but the energy consumption and the risk of frost blocking the road on the heat exchange surface rise simultaneously, and reasonable working conditions should be set according to the emission limit and medium characteristics, taking into account the operating cost.
LuoyangWohong PetrochemicalEquipment Co., Ltd. provides design, manufacture, installation, commissioning and operation and maintenance services for vinyl acetate and other media recovery devices for chemical enterprises. Welcome to contact and exchange.
This article is organized by Luoyang wohong petrochemical equipment co., ltd. if you need to evaluate the recovery scheme of vinyl acetate and other media or conduct on-site investigation, please contact and exchange.
Mr. Li 13526990215
Hotline
