Operating problems of the circulating water system
Thread Content
I would like to ask the experts: in our factory, the pressure of the circulating water at the outlet is 0.35 MPa, while the pressure at the inlet is 0.232 MPa. However, the temperature difference is only 6 degrees – neither the pressure difference nor the temperature difference meets the design specifications (pressure difference of 0.2 MPa, temperature difference of 10 degrees). The temperature of the heat exchanger is currently high; could this be due to scaling on the heat exchanger or a low pressure difference?
The issue of fouling in heat exchangers needs to be taken into account, as it directly affects the heat exchange efficiency. Is the backflow pressure a bit higher? Are there any valves that are not fully open on the return pipe, or other factors that affect the water flow? Has the pressure difference reached 0.2 MPa? It seems that the backflow is restricted, resulting in insufficient water flow and poor heat exchange efficiency
The valve opening at the top tower is small, so the water outlet pressure is already very low
The increase in temperature caused by scaling in the heat exchanger is a gradual process; if a high temperature is detected in a short period of time, it may be due to insufficient valve opening, a clogged filter, or problems with the pump itself that result in insufficient water flow
Also, check whether the circulating water bypass is open
Is the circulating water pump undersized?
:Shut up: It doesn’t matter if the pressure difference is low; what’s important is the temperature difference of 10 degrees. What is the temperature set for the circulating water in your system? If the temperature difference is low, is it because the return water temperature is high or the outlet water temperature is high? Check whether there are any problems with your cooling tower. Another possibility is scaling in the condenser – monitor the water temperatures at the inlet and outlet of the condenser. As long as the water used isn’t groundwater, by adding chemicals in the correct amounts and draining water regularly, scaling will be minimal
Is the flow rate through the heat exchanger stable, and is there any uneven water flow caused by multiple heat exchangers?
A pressure difference at the bottom indicates high resistance in the return pipe, and it is also possible that the total flow rate exceeds the designed value. What is the temperature of the water supply? Does it meet the specified requirements? If this is the case, it could be a problem with heat transfer in the heat exchanger. If the feedwater temperature is high, it might be a problem with the cooling tower. Check them one by one.