At present, industrial boilers in the market generally exist this phenomenon: the combustion efficiency is designed very high by the factory, but the optimal combustion effect is often not achieved in the actual operation of the boiler, and the efficiency will become lower and lower. This is also caused by many reasons, among which the main factors are: heat loss of boiler exhaust gas, heat loss of gas incomplete combustion, heat loss of solid incomplete combustion, heat loss of boiler heat dissipation, heat loss of ash and slag materials, etc.
Following these factors, EPCB Boiler summarizes several measures to improve efficiency to help users effectively improve the thermal efficiency of the boiler, let’s take a look.
(1) Reuse of waste heat from boiler flue gas, and energy-saving equipment such as economizer and condenser are equipped. The heat loss of flue gas is an important factor that causes the reduction of boiler thermal efficiency. The higher the exhaust gas temperature of the boiler, the greater the heat loss of the exhaust gas, so reducing the exhaust gas temperature is a good way to improve the thermal efficiency of the boiler. In order to reduce the flue gas temperature, most factories will choose to equip flue gas waste heat recovery devices, such as economizers, condensers, etc. They can reuse the high temperature flue gas generated at the boiler tail, effectively reduce the flue gas temperature and improve the thermal efficiency of the boiler.
(2) Rationally control the proportion of air to fuel so as to make combustion more fully and reduce the loss of incomplete combustion of fuel and heat loss of exhaust gas. If the air coefficient is too high, the excess cold air inhaled during combustion will not participate in combustion. When the fuel is burned, this part of the cold air will be heated, resulting in lower furnace temperature. After heating, this part of air will be wasted in vain with the emission of flue gas, resulting in increased heat loss of exhaust gas. If the air coefficient is too low, the incomplete combustion will be caused by insufficient oxygen in the fuel. At this time, the heat transfer efficiency of the boiler will be greatly reduced and the incomplete combustion loss will increase. Therefore, reasonable control of air-fuel ratio, as far as possible to reduce exhaust heat loss and incomplete combustion loss, is another way to improve the thermal efficiency of boilers.
(3) Strictly control the quality of boiler feed water to avoid serious scaling of boilers. If the boiler feed water is not softened reasonably, it will contain a large number of impurities and easily scaled substances such as calcium and magnesium ions. It is unavoidable that scaling will occur when such feedwater is used for a long time. Because the thermal conductivity of scale is very low, once the boiler heating surface scales, the heat transfer of the boiler decreases, the exhaust gas temperature will rise, the heat loss of the exhaust gas will increase, and the thermal efficiency will naturally decline. Therefore, it is also criticized that boiler users should configure reasonable softening water devices, regularly detect the scales in the boiler, and timely clean up the scales.
(4) Strengthen the thermal insulation of the boiler system and reduce the loss of heat dissipation. During the operation of the boiler, the temperature of the boiler body, steam pipeline and steam distribution cylinder will always be much higher than that of the air in the boiler room, so part of the heat will be lost to the surrounding air by radiation and convection, which will become the heat loss of the boiler. Therefore, boilers and steam pipeline systems should be equipped with insulation layer, textile insulation layer damage, reduce heat loss.