Stack temperature is the temperature of the combustion gases (dry and water vapor) leaving the boiler. A well-designed boiler removes as much heat as possible from the combustion gases. Thus, lower stack temperature represents more effective heat transfer and lower heat loss up the stack. The stack temperature reflects the energy that did not transfer from the fuel to steam or hot water. Stack temperature is a visible indicator of boiler efficiency. Any time efficiency is guaranteed, predicted stack temperatures should be verified.
Stack loss is a measure of the amount of heat carried away by dry flue gases (unused heat) and the moisture loss (product of combustion), based on the fuel analysis of the specific fuel being used, moisture in the combustion air, etc.
The combustion air preheater is definitely one of heat exchanger applications. Based on Figure 1 below, flue gas simply leaves steam boiler and passes via air preheater. The combustion air is passed through this equipment too to increase its temperature before being combined with boiler fuel.
Because the temperature of combustion air is lower than the temperature of flue gas, combustion air receive heat transfer from flue gas through combustion air preheater in the process of convection heat transfer. The heat transfer make temperature of flue gas lower and consequently minimizes its heat loss and also decreases the air temperature to stack.
A thermal fluid system is a closed loop using mineral or synthetic oil as the heat transfer fluid. These systems operate at elevated temperatures while maintaining low system pressures. Fluid is circulated within the heater tubes and flue gases heat the fluid.
1. In terms of boiler body structure, WNS series gas-fired (oil-fired) boilers are fire tube boilers; SZS series gas-fired (oil-fired) boilers are water tube boilers;
2. In terms of boiler working pressure, if the boiler pressure is below 1.6Mpa, the choice is usually the WNS series gas-fired (oil-fired) boiler, if the boiler pressure is above 1.6Mpa, the SZS series gas-fired (oil-fired) boiler may be a better solution. Some high-pressure boilers also adopted SZS series gas-fired (oil-fir...
(Question details) Specific performance:The temperature difference between the inlet oil and the outlet oil temperature of the boiler exceeds the given value.Answer：Cause of failure:(1) The oil supply of the heat oil circulating pump is insufficient.(2) The boiler operates overload.(3) Thermal oil metamorphism.(4) The boiler does not match the heating equipment.(5) Bad insulation effect.(6) There is gas or steam in the thermal oil. Troubleshooting:(1) Remove the faults of oil pump and pipeline.(2) Operate at normal load.(3) Change new oil.(4) Choose proper boiler.(5) Check the insulation layer and repair the loopholes.(6) Remove air or steam. ZOZEN pays much attention to boiler furnace insulation also, the inside is made of high quality insulation material, external use of stainless steel plate, which can maximumly reduce heat loss and improve the operating environment.
Question details (performance):A pump in a gas boiler does not transfer oil. Answer: Fault reason:(1) Pump failure.(2) Oil pressure and power are reduced.(3) The oil inlet valve is not sealed.(4) The inlet pipe is not sealed.(5) The interceptor valve is closed.(6) The filter is contaminated.(7) The filter is not sealed.(8) The tubing is not sealed.(9) Pump suck air inlet.(10) The vacuum degree in oil tube is too high.Troubleshooting:(1) Replace with new pump.(2) Remove the inlet valve and clean or replace it.(3) Seal the inlet pipe.(4) Open.(5) Cleaning.(6) Replace the sealing ring.(7) Tighten and exhaust.(8) Clean the filter and valve.
