Study on Petroleum Wharf and Reservoir VOCs Emissions and Photochemical Reaction

Abstract

Focusing on the environmental problems caused by VOCs emission and photochemical reactions in petroleum wharf and reservoir areas, a field experiment was conducted in Zhanjiang port. The VOCs emission and photochemical reaction, VOCs source model and the photochemical reaction mechanism were discussed. Through analyzing and comparing the measured and simulated results, firstly, a simplified mechanism model with the chain reaction balance coefficient is developed; secondly, VOCs emission amount during the temperature rising period (3h daily) is corrected as doubling the normal dose; thirdly, VOCs consumption amount during the photochemical reaction period (6h daily) is estimated as being 71.8% of VOCs emission amount; finally, the derived photochemical reaction equilibrium coefficient of O3 and PM were 0.084 and 0.79. Seven kinds of emission source models (including pipeline and valve leakage, fixed tank big breath with oiling, floating roof tank oiling and pumping loss, fixed tank small breath with temperature rising, oil storage still loss of internal and external floating roof tanks, ship and tank loading emissions) were applied to analyze the operation scenario and emission inventory in typical petroleum wharf and reservoir areas, of which the annual throughput is 3000 ´ 104 tons, and the annual average temperature is 22 °C. The calculated annual VOCs emission with modification is 1555.88 t. Using the VOCs emission and photochemical reaction models for different regions of the port, VOCs and PM emission inventories of major Chinese ports were calculated. The total emission amounts of VOCs and PM in 2012 were approximately 43296 t and 6140 t, mainly distributed in the port group located areas in Yangtze River Delta, Bohai rim and Pearl River Delta, as well as Beibu Gulf, Strait West. As the emission sources located more densely and the emission more intense, there will be more adverse cumulative effect on the regional air quality. Therefore, it is necessary to adopt more active and effective air pollution prevention and control measures in petroleum wharf and reservoir areas.