Dewatering of livestock waste using by liquefied dimethyl ether

采用液化二甲醚(DME)在常温、低能耗条件下对畜禽粪便脱水进行了实验研究，结果表明，当DME用量为38mL/g粪便，脱水时间为70min时，牛粪中80%的水分含量降至5.7%，为最佳脱水条件。在此条件下，脱水粪便的湿基低位热值是原牛粪的18倍，液化二甲醚脱水降低了粪便的气味和自热性。至于兽医使用的药用产品的行为，疏水程度越高的药材对液化二甲醚的萃取率越高。因此，DME脱水系统可以通过疏水环境进行控制。

In this study, an advanced dewatering process for livestock manure, operated at room temperature with low energy requirements due to the use of liquefied dimethyl ether (DME), was investigated experimentally to generate dry livestock manure as a solid fuel.The results showed that the 80% water content in cattle manure was decreased to 5.7% when DME was applied at 38 mL-DME/g-manure with a 70 min dewatering time, which represented the optimized dewatering conditions. Under these conditions, the wet based lower heating value of the dewatered manure was 18 times higher than that of the original cattle manure, and odor and self-pyrogenicity of the dewatered manure were decreased by liquefied DME dewatering. As for the behavior of the medicinal products used by veterinarians, the more hydrophobic medicinal products is, the higher it have an extractability by liquefied DME. Therefore, a DME dewatering system could be controlled by hydrophobic environment.