What issues need to be paid attention to when using graphite multi-effect concentration device?
- 2019-11-09-

In large-scale industrial production, it is often necessary to evaporate a large amount of water, which requires a large amount of energy to heat the water to generate steam. In order to reduce the consumption of heating steam, multi-effect evaporation can be used. We use Graphite multi-effect enrichment device Manual operation, need to pay attention to the following points:

1. The steam pressure is stable and often observed.

2. The degree of vacuum and temperature meet the requirements. Under negative pressure operating conditions, fluctuations are found and the cause is found.

3. Adjust the discharge valve so that the specific gravity of the discharge meets the requirements. Timely measurement, more measurement when the equipment is unstable; under normal circumstances, there should not be much change.

4. Adjust the feeding valve to make the liquid level stable in the middle position of the sight glass.

5. Vacuum pump, circulation pump and condensate pump are running normally.

6. If the temperature keeps rising, first see if the vacuum is tripped, and then see if the condensate is not discharged. No problem, see if the steam pressure suddenly rises, or it may leak. Stop the pressure to determine the problem.

7. If the temperature rise is found, close the steam valve to see if the vacuum pump has tripped. If so, close the vacuum pump inlet valve. Did not jump, check each state, wait for the temperature to fall back, then turn on.

Corrosive solution. When the corrosive solution is evaporated, the heating tube should be made of the specified material or lined with corrosion-resistant material. If the solution is not afraid of contamination, it can also be used to directly heat the evaporator. The viscosity of the solution and the range of viscosity change during the multi-effect evaporator evaporation are important factors for selection. There was a solution precipitated from the crystals. When crystals in the solution are precipitated, an external heat evaporator or a forced circulation evaporator should be used. The solution is thermally stable. When the solution is easily decomposed, polymerized, and scaled easily for a long time, it should use an evaporator with less stagnation and short residence time. The amount of solution and the amount of solution should be considered. When the heat transfer surface is greater than 10, it is not recommended to use a scraper to stir the thin film evaporator. When the heat transfer surface is more than 20, a multi-effect evaporator can be used. Easy-to-expand solution, no matter which kind of solution evaporates, after a long time of use after evaporation, there will always be dirt on the heat exchange surface. Due to the small thermal conductivity of the scale layer, it is necessary to choose an evaporator, a solution that is easy to clean and the circulation speed of the solution, and easy to scale. Easily foaming solution, the foamable solution will generate a large number of overlapping layers when it is evaporated, and the foam will not easily burst, filling the entire separation chamber, that is, the two vapors are discharged, not only the loss of materials, but also the condenser.