Abstract: <SPAN lang=EN-US style="FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman"; mso-bidi-font-size: 12.0pt; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体">In order to improve recycling rate of potassium resources,tail washings discharged from the processing workshop was used to mix with old brine in proportion to produce low-sodium carnallite ore.Due to the higher contents of calcium sulfate and fine salt in this ore,the washing effect of filter cake was affected which led to low quality and yield of<SPAN style="mso-spacerun: yes">&nbsp; </SPAN>potassium chloride product.Washing experiments with the same quantity of filter cake under the different conditions,such as different compositions of filter cake,washing times,and amounts and concentrations of washing water,were carried out.Experiment results showed that the washing concentration was about 47% when temperature of washing water was 15 </SPAN><SPAN style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman"; mso-bidi-font-family: "Times New Roman"; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">℃</SPAN><SPAN lang=EN-US style="FONT-SIZE: 10.5pt; FONT-FAMILY: "Times New Roman"; mso-bidi-font-size: 12.0pt; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体">,controlling the mass fraction of sodium chloride in filter cake at 10%~11%,mass fraction of calcium sulfate less than 2%,moisture content lower than 15% and doubled theoretical amounts of water for washing 6 min.Not only concentration requirement of centrifugal dewatering was met,but also mass fraction and yield of potassium chloride in the product were about 93% and 90% respectively,and washing effect was the best.</SPAN><SPAN style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 12.0pt; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman"; mso-bidi-font-family: "Times New Roman"; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"></SPAN>