FAQ about VNOR and MVR Evaporators

When MVR processes raw material COD, it is divided into light components and heavy components. Light components are generally volatile and can enter concentrated water and be removed in the preheating stage; heavy components will form bottom liquid and will not evaporate. So treat them differently. Silicate will scale under alkaline conditions, which will affect the heat exchange tube.

MVR generally adopts 85-90 degree evaporation to ensure the reliability and energy saving of the system, but there will be different requirements according to different materials.

The energy consumption of the compressor refers to the power of the compressor, excluding the power consumption of other pumps and centrifuges.

It is recommended not to use titanium when there are fluoride ions. Titanium has poor corrosion resistance to fluoride ions. It can be considered to evaporate at around 70 degrees Celsius using 2205 to avoid the dual corrosion of fluoride and chloride ions.

Cause of the problem: The filter may be clogged.
Treatment method: Check the filter element of the pipeline line, if there is blockage, clean the blockage or replace the filter element.

Cause of the problem: No circulation or minimal circulation.
Treatment method: Check whether the valve of the circulation pipeline is open, and check whether the circulation pump is working normally. 

Cause of the problem: There is an air leak in the MVR evaporator system.
Treatment method: Check the connection points of each connection part of the MVR evaporator system and deal with air leakage points.

Cause of the problem: The inner wall of the main heater pipeline side is encrusted or has too many attachments.
Treatment method: Start and execute the system cleaning program to perform online cleaning of the MVR evaporation system.

 Cause of the problem: The liquid level in the MVR evaporator separator is too high.
 Treatment method: Lower the liquid level in the separator of the evaporator.

 

Cause of the problem:
 （1）The temperature rise provided by the compressor does not reach the design value;
 （2）Compressor cooling water flow is too large;
 （3）The tube side of the heat ex-changer is too dirty, and the fouling coefficient is large, which reduces the heat transfer effect of the heat ex-changer;
 （4）The high level of distilled water in the shell side of the heat ex-changer leads to a reduction in the evaporation area;
 （5）The non-condensable gas pipeline is not smooth, resulting in excessive gas pressure in the heat ex-changer.

Treatment method:
 （1）Check the operation status of the compressor or increase the compressor speed;
 （2）Adjust the cooling water flow;
 （3）Shut down to clean dirt;
 （4）Check the operation status of the condensate pump or check the status of the condensate pump outlet pipeline;
 （5）Check the condition of the non-condensable gas discharge line.