Sell products such as solid alkali set equipment and high-end pumps
32%-50% Technological Process
- Time of issue:2020-12-15 09:35:07
Finished 50% Alkali
On the premise that the raw material alkali meets the standard, 100% excellent product of 50% alkali is achieved.
NaOH ≥ 50% wt
Na2C03 ≤ 625 ppm wt
NaCI03 ≤ 40 ppm wt
Fe203 ≤ 6 ppm wt
NaCI ≤ 62.5 ppm wt
Temperature: 45 degrees
0.8 MPa steam is passed through the steam regulating valve and enters the I Effect Evaporator (E0109). The steam condensate is heat exchanged by two heat exchangers (E0107) and (E0104), which are sent out of the boundary area by their own pressure and can be used as boiler feeding water. The secondary vapor produced by I effect evaporator acts as the heating medium of the II effect evaporator (E0106), and the II effect condensate enters the condensate tank (V0101). The secondary vapor produced by the II effect evaporator acts as the heating medium of the III effect evaporator (E0103), and the III effect condensate enters the condensate tank (V0101). The secondary steam produced by III effect evaporation condenses in the surface condenser (E0101), and the vacuum pump (P0101) sucks the negative pressure. The condensate produced enters the condensate tank (V0101), which is uniformly sent to the boundry outside by the condensate pump (P0102).
Three-effect counter-current falling film evaporation technology was used to concentrate raw 32% alkali to 50%, and then cooled to 50% finished alkali. The steam needed for heating was 0.8 MPa.
Brief Introduction of Process Flow
32% NaOH lye from boundary area was added to the III effect falling film evaporator (E0103), and the concentration increased from 32% to 36%. After concentration, the lye is pressurized by the III effect alkali pump (P0103), heated by the E0104 and E0105 heat exchangers, then enters the II effect falling film evaporator (E0106). The concentration of lye increased to 42%. After concentration, the lye is pressurized by the II effect alkali pump (P0104) and heated by the E0107 and E0108 heat exchangers, then enters the I effect falling film evaporator (E0109), the concentration was increased to 50%. The concentrated lye is pressurized by the I-effect alkali pump (P0105) and cooled to 45C by the heat exchanger of E0108 and E0105 and the alkali cooler (E0102) and sent to the finished alkali tank outside the boundary for storage.
1. Circulation water: Low temperature water from circulating water system is sent back to circulating water system for cooling after heat exchange by surface condenser and lye cooler.
2. Condensate water: High temperature condensate water produced by falling film evaporator is used to preheat lye, and the condensate water after heat exchange is sent out of the boundary area.
3. Condensate from surface condenser and condensate from II and III effect falling film evaporator are recycled into condensate tank and pumped out of the boundary area for use.
1. The process uses three-effect countercurrent falling film evaporation, due to the simple process, easy to operate and control, and the production is stable.
2. Control system: DCS automatic control system is used to realize remote control. Valves with high operating frequency adopt control valves; key parameters such as temperature, flow rate, pressure and current are displayed on the computer screen of DCS operation station, and can be used as signal source to control the control valves; the equipment start and stop can be controlled by DCS and field.