低温型车用尿素溶液冰点影响因素研究
Study on the Factors to Freezing Point of Low Temperature Aqueous Urea Solution for Diesel Engines

针对低温型车用尿素溶液在使用过程中冰点指标不稳定这一问题，进行了影响冰点因素的研究。主要考察了低温改进剂种类及浓度、调配水温、加料顺序、储存时间等因素，结果表明上述因素对冰点都有不同程度的影响。选择合适的低温改进剂，在较高的水温下(30℃)完全溶解并保温一定时间，产品的理化性能较为稳定，冰点这一指标也能稳定地保持在？30℃以下。
To solve the problem of unstable freezing point for low temperature aqueous urea solution in the usage, the factors influencing the freezing point were studied in this paper. The factors such as the type and concentration of low-temperature improvers, the temperature of the mixing water, the order of feeding and storage time were mainly investigated. The results showed that the above factors have different effects on the freezing point. Select a suitable low-temperature improver, dissolve completely at a relatively high water temperature (30？C) and keep it for a certain period of time. The product’s physical and chemical properties are relatively stable, and the index of freezing point can be stably maintained below ？30？C.