In the caprolactam production process,ammonium sulfate grains inevitably entrain a small amount of amide oil,when the grains settle and separate in the gas-liquid-liquid-solid crystallization reactor.Amide oil entrainment causes waste of caprolactam and pollution of ammonium sulfate.By adding surfactants and changing experimental conditions,the entrainment of amide oil was reduced.The influence of surfactant,pH,temperature,and grain size on adsorption behavior of amide oil on the surface of ammonium sulfate crystal was evaluated from the adsorption equilibrium under shaking.The results show that cationic surfactant cetylpyridinium bromide(CPB),dodecyltrimethylammonium bromide(DTAB),non-ionic surfactant Tween 80,and the mixture of non-ionic surfactant Triton X-100 and DTAB reduce the caprolactam adsorption on the surface of ammonium sulfate crystals,while anionic surfactant sodium lauryl sulfate(SDS)and sodium dodecyl benzene sulfonate(SDBS)increase the caprolactam adsorption.In the range of 2—7,pH does not significantly affect the adsorption behavior.Between 50—80℃,amide oil adsorption on the surface of ammonium sulfate increases with temperature.With increasing ammonium sulfate particle size,the adsorption of amide oil decreases.
在内径160 mm,高300 mm 的玻璃槽中,采用0～200 W 可调功聚能型超声波发生器研究了超声波功率、聚能头与进气管距离、聚能头放置方式、聚能头投入深度、进气流量和反射室直径等因素对气液鼓泡流中气泡发生频率的影响。实验结果表明,聚能头竖直放置时,随着功率的增加,单位时间内气泡数目先减少而后急剧增加;聚能头水平放置时,单位时间内气泡数目随着功率增加而增加;聚能头距分布管越远,超声波对气泡的破碎作用越小,气体流量越大,单位时间内气泡数目越多,反射室直径在一定范围内越小,单位时间内气泡数目越多。
