Triple-effect Forced Circulation Evaporator for Mix Salt Wastewater Treatment
Evaporator: Triple-effect Forced Circulation Evaporator;
Application: Industrial wastewater treatment;
Working medium: High salinity wastewater, containing sodium chloride, potassium chloride and sodium sulfate mainly, with solid content 20%wt;
Evaporation capacity: 3,000kg/hr;
Steam consumption: 420kg steam per ton water evaporation;
Construction material: product wetted parts adopt 2205, non wetted parts adopt SS316L or carbons steel per actual need.
Project Description
In this project, mix salt wastewater was treated, which contains high salt content of sodium chloride, potassium chloride and sodium sulfate, with solid content 20%wt. According to the feature of the feedstock, a triple-effect forced circulation with concurrent and mixed flow process was adopted, the concentrate was output from all the three effect, ensure the concentrate was output at proper temperature, preventing COD enrichment which would lead to tube blockage.
Process Technology
A triple-effect forced circulation evaporator was adopted for the high salinity wastewater treatment, and the overall process flow was: the high salinity wastewater was concentrated by a triple-effect forced circulation evaporator from 205 to 50%, and then the oversaturated liquor was transferred into a centrifuge for liquor-solid separation, and the solids separated were treated furtherly, and the mother liquor were returned to the evaporator to be concentrated again.
Equipment Description
One set of triple-effect central circulation evaporator was adopted, which is able to meet the following demands:
1). The high salinity wastewater containing mix salt is concentrated from over-saturation;
2). All components in the plant are well designed to ensure safety in production.
3). The forced circulation pump equipped can effectively prevent blocking risk of heat exchange tubes caused by high concentration of solid salts, and can slow the formation of scaling on the heat exchange surface at the mean time, improve the heat transfer efficiency, increase the continuous operation time of equipment, and reduce the cleaning frequency;
4). The main configuration of the plant is as below:
a. One set of double-effect central circulation evaporator, which consists of desuperheater & decompressor, heaters, evaporators, condenser, forced circulation pump, and vacuum unit;
b. One set of centrifuge and mother liquor collecting and returning system;
c. One set of heat recovery system recovering condensate water;
d. One set of PLC control system.
