A Review of Research on Vapour Recovery Technology

Introduction to the treatment of volatile organic compounds
The control of volatile organic compounds (VOCs) emissions is of great significance in improving air quality, protecting the ecological environment, safeguarding human health and promoting green development.

The State Council on the issuance of the "14th Five-Year Plan" energy saving and emission reduction comprehensive work program notice pointed out that the petrochemical and chemical industries should deepen the treatment of volatile organic compounds pollution, comprehensively improve the collection rate of exhaust gas, the synchronization of the operation rate of the treatment facilities and the removal rate. The relevant air pollutant emission standards promulgated in recent years require that oil storage depots, oil transportation vehicles, and gas stations must follow the requirements of vapour emission control in the process of storing, receiving and distributing oil, in order to reduce the emission of VOCs. vapour recovery technology is an important environmental protection measure in the petrochemical industry, aiming to reduce VOCs emissions and improve energy utilization. Currently, the mainstream vapour recovery technologies include condensation, adsorption, absorption, membrane separation and their integrated processes.

In recent years, vapour recovery technology research has focused on the optimization of a single technology and the development of multi-level integrated processes. Condensation research focuses on condensation temperature, pressure, initial concentration and process optimization. Adsorption method focuses on the adsorption performance of different adsorbents.

A large number of experimental studies have been carried out on the adsorption performance of different adsorbents, explored the preparation and modification of new adsorbents, and continuously carried out the development of polymer membranes and the study of adsorbent regeneration technology. However, there are still some shortcomings in the current research. On the one hand, for single vapour recovery technology, although certain results have been achieved in theoretical and experimental studies, further optimization of process parameters and equipment design is still required to achieve higher recovery efficiency and lower emission concentration in practical applications. On the other hand, although the integrated vapour recovery technology can give full play to the advantages of each single technology, the research on energy coupling, material balance, and stability control in the process of system integration is not deep enough and systematic enough, which leads to the problems of higher energy consumption, more expensive operation cost, and complicated operation of some of the integrated processes in actual operation.

Therefore, this study aims to comprehensively sort out and analyze the latest research progress of vapour recovery technology, and discuss the optimization direction of single technology and the improvement strategy of integrated process.

This paper will focus on the principles, characteristics, applications, and research status of four commonly used vapour recovery technologies, namely, condensation, absorption, adsorption, and membrane separation, and introduce the research progress and development direction of the integrated vapour recovery process. The process flow, key influencing factors, advantages and disadvantages of each single technology will be analyzed in depth.

The advantages and disadvantages of each single technology will be analyzed in depth, and their application effects in different scenarios will be discussed with practical cases. For the integrated process section, the common combinations and their synergistic mechanisms will be elaborated in detail. By comprehensively summarizing the existing research results, we aim to provide a comprehensive overview for the future research and practical application of vapour recovery technologies.

Recovery Technology, and help to realize more efficient, economical, and practical application of vapour recovery technology.
The aim is to provide references for future research and practical application of vapour recovery technology, and to help realize the goal of vapour recovery in a more efficient, economical and environmentally friendly way.

The vapour recovery system of a gas station is generally divided into three stages: primary vapour recovery system (unloading vapour recovery system), secondary vapour recovery system (dispenser vapour recovery system), and tertiary vapour recovery system (vapour emission treatment device). The primary vapour recovery system is mainly used when tanker trucks unload oil into the storage tanks of the gas station, and collects and re-conveys the vapour to the tanker trucks or storage tanks through a closed connection system. Secondary vapour recovery systems work during the refueling process, capturing the vapour through a recovery device on the fueling gun and transporting it back to the storage tank. Tertiary vapour recovery systems provide in-depth treatment of the remaining vapour, often using technologies such as adsorption, absorption, condensation, and membrane separation to remove or recover the hazardous components of the vapour.