Energy-saving measures for hot water boiler house for gas heating.
Gas heating hot water boiler room should take reasonable energy saving measures to effectively improve the level of energy saving. Among the factors with energy saving potential, the recovery rate of condensate water and the recharge rate of hot water heating hot water boiler system are actually related to the external network and thermal users, which should be solved through the external network and thermal users. In this paper, the energy saving measures will be analyzed and studied from the other four aspects.
(1) Analysis of measures to reduce the heat loss of smoke exhaust
The heat loss of smoke exhaust is mainly affected by exhaust temperature and excess air coefficient .
The excess air coefficient is too large, which will lead to the increase of smoke volume and take away more heat, so the excess air coefficient should be reduced as much as possible under the premise of ensuring the combustion efficiency of heating hot water boiler, and the burners can be arranged reasonably. The strict operation and debugging make it match with the structural characteristics, fuel types and characteristics of the heating hot water boiler body, so as to ensure that the flame is filled in the furnace tank and the fuel is fully burned. The selection of burners with proportional adjustment function can automatically adjust the supply of gas and the ratio of air with the change of heating load, so that the hot water boiler of gas heating can always be kept in a high range of load. At the same time, the combustion efficiency is guaranteed to ensure a reasonable excess air system, and the heat loss of exhaust smoke is reduced to improve the thermal efficiency of heating hot water boiler.
Because the heat loss carried by water vapor accounts for 55% �� 75% of the heat loss of exhaust smoke, if the exhaust temperature is reduced below the condensation temperature of flue gas, the latent heat of steam can be recovered and utilized, and the heat loss of exhaust smoke can be reduced very effectively. Improve the thermal efficiency of heating hot water boiler. Therefore, it is necessary to adopt low temperature endothermic device and achieve condensation effect for heat recovery. The low temperature endothermic device can be divided into integral type and separated type in structure. The integral type is the condensing heating hot water boiler, and the separated type is to install the waste heat recovery device in the flue outside the conventional heating hot water boiler.
(2) Condensing heating hot water boiler
Condensing heating hot water boiler refers to the heating hot water boiler which can absorb the vaporization latent heat contained in steam from the flue gas discharged from the heating hot water boiler. Conventional heating hot water boilers transfer most of the sensible heat in flue gas to feed water or steam, while condensing heating hot water boilers not only transfer a larger part of sensible heat to feed water or steam. It also absorbs the latent heat of vaporization released from the condensation of water vapor in part of the flue gas.
The design idea of condensing heating hot water boiler is very different from that of traditional heating hot water boiler. Condensing heating hot water boiler must have condensing heat exchange heating surface and adopt high performance shell heat preservation and sealing material. The exhaust smoke temperature of the heating hot water boiler is reduced to below the condensation temperature of the flue gas with low temperature water, so that the steam in the overheated state of the flue gas condenses into water, releases the latent heat of vaporization, and still makes use of this part of the heat recovery in the heating hot water boiler. According to the low emission of fuel, the overall efficiency is 10% and 17% higher than that of the traditional shell heating hot water boiler. The exhaust temperature can be reduced to 50 �� ~ 70 ��. . The condensing heating hot water boiler not only saves energy, but also removes the harmful substances in the flue gas and recovers considerable water quantity while condensing the steam in the flue gas, which has the characteristics of energy saving, water saving and environmental protection. Condensation heating hot water boiler has been widely used in foreign countries.
(3) installation of waste heat recovery device in conventional heating hot water boiler
The separated flue gas waste heat recovery device can be divided into direct contact heat exchanger and indirect heat exchanger.
The direct contact heat exchanger uses water spray to contact the flue gas directly for heat and mass exchange. The recovery rate of heat energy in this method is high, and a large number of harmful substances in flue gas are absorbed at the same time. However, the water quality recovered by this method is acidic and its use is restricted. The hot water produced by waste heat recovery is difficult to use in the general civil heating hot water boiler room. Therefore, heating hot water boiler room generally does not use this method.
Indirect heat exchanger is also called flue gas condensation heat energy recovery device. Because of the high content of water vapor in the flue gas of the gas-heated hot water boiler, the water vapor in the flue gas emits a large amount of vaporization latent heat in the condensation process. The effect of condensing waste heat recovery device used in gas-fired hot water boiler is higher than that in traditional coal-fired heating hot water boiler. The installation of flue gas waste heat recovery heat exchanger on the flue of conventional heating hot water boiler can improve the thermal efficiency of heating hot water boiler, reduce the waste of energy, and at the same time reduce the operation cost of users.
