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.
Efficiency is especially important on a large scale and manufacturing and production operations are no exception. Here are two key reasons why you may want to consider upgrading your industrial heating equipment or installing a new, highly efficient thermal fluid heating system in your plant or facility.
A dryback boiler has a rear wall that is lined with refractory, a wetback boiler has a rear wall that is jacketed by water. Because of this fact, wetback boilers typically boast higher efficiency than dryback boilers as the heat from combustion goes directly into heating water instead of refractory. Wetback boilers are also more forgiving with load changes as the reversal chamber of the boiler is totally submerged in water creating an even heat transfer on the intermediate tube sheet to furnace joint.
Today's businesses, regardless of industry, can always do more to improve their sustainability and limit the negative impact their actions have on the environment. There are a number of ways to do this, but one of the best is to use a boiler that's designed to limit the emissions of NOx — one of the most harmful greenhouse gases humans emit into the atmosphere. Aside from being good for the environment, a low NOx boiler can also be good for business.
The choice between a steam system or a thermal fluid system is governed by the process requirements. The range or process temperature is a deciding factor. If the system’s required temperature is above the freezing point of water (0°C) and below approximately 160°C, the choice is usually steam. However, if the required temperature is above 160°C, thermal fluid may be a better solution. Thermal oil heater systems can be designed with maximum operating temperatures to 325°C.
Steam carries about 540 Kcal/kg of useful energy whereas hot water and thermal fluid carry much less energy. Steam does not require a pump to transfer the energy. Generally, if the heating temperatures required are <100°C, then hot water can be used and if temperatures >180°C are needed then thermal fluid might be a better choice. For process temperatures between 100°C and 180°C steam is considered a viable option.
(Question details) Specific performance:There is hammer sound in the oil inlet pipe, and the pointer of the inlet and outlet pressure gauge fluctuates.Answers: Cause of failure:The system contains gas and moisture.Troubleshooting:(1) Exhaust air.(2) Cook oil.