载气增湿蒸发技术处理切削废液的研究

Study on carrier gas humidification and evaporation technology for treatment of cutting waste liquid

利用空气作为载气,采用蒸发塔进行了载气增湿蒸发浓缩切削废液的实验,探究了操作条件对蒸发过程的影响。随着载气流量的增加,容积传质系数、蒸发量和整塔压降均增大,出口载气VOC浓度减小;随着载气温度、循环流量的增加,容积传质系数、蒸发量、整塔压降和出口载气VOC浓度均增大。实验条件下容积传质系数及蒸发量最大达到了13.95 g·(m^(3)·s)^(-1)和3.39 kg·h^(-1);出口载气VOC浓度最大为6.2 mg·L^(-1),小于《大气污染物综合排放标准》中规定值。研究结果表明载气增湿蒸发工艺能有效浓缩切削废液,为工业化应用奠定了基础。

Using air as the carrier gas, the evaporation and concentration experiment of cutting waste liquid was carried out in the evaporation tower, and the influence of operating conditions on the evaporation process was explored. With the increase of carrier gas flow rate, the volumetric mass transfer coefficient, evaporation capacity, and pressure drop all increase, and the VOC concentration of the outlet carrier gas decreases. With the increase of carrier gas temperature and circulation flow rate, the volumetric mass transfer coefficient, evaporation capacity, pressure drop and the outlet carrier gas VOC concentration all increase. Under the present experimental conditions, the maximum volumetric mass transfer coefficient and evaporation are 13.95 g·(m^(3)·s)^(-1)and 3.39 kg·h^(-1), respectively. The maximum VOC concentration of the outlet carrier gas is 6.2 mg·L^(-1), which is less than the value specified in the Comprehensive Emission Standard of Air Pollutants. The results of researches show that the carrier gas humidification evaporation process can effectively concentrate the cutting waste liquid, laying a foundation for industrial application.