COMPARATIVE CHARACTERISTICS OF UTILIZATION INSTALLATIONS OF FLUE GASES OF BOILERS WITH HUMIDIFICATION OF AIR

Reduction of natural gas consumption in industrial and municipal heat power engineering in particular industrial CHP`s (combined heat and power plant) and boilers plants can be achieved by increasing its utilization rate. It is known that the smoke gas temperature in the outlet of many steam and hot water boilers exceeds 140 oC, which is also characterized by increased heat loss with flue gases and low efficiency of these units. The use of utilization installations of flue gases for deep cooling of combustion products below the dew point temperature will increase their efficiency and in general increase the COP (coefficient of performance) of the boiler and reduce the consumption of natural gas. Condensing contact mixing heat exchangers or film heat exchangers or surface heat exchangers can be used for these purposes. In last years the requirements to the operation of boilers are increasing for reducing emissions of nitrogen oxides that are harmful to the environment. One of the effective methods of reducing nitrogen oxides is humidification of air, for example, in contact air heaters. The methods and results of calculations of energy and ecological efficiency of heat utilization installations with KTAN (contact heat exchanger with active header) utilizer and KTAN air heater, ecologically clean installation and surface utilizers-heaters are given in the work. Calculations were performed for units installed in a water-heating boiler house in Kyiv with a KV GM-10 (water-heating boiler that burns gas and fuel-oil) water-heating boiler. It is shown that the surface utilize heater unit is characterized by the highest indicators of energy and environmental efficiency. It has the highest power of utilized heat (2312 kW) and the lowest operating and consolidated costs (25950 and 119140 UAH / year, respectively), as well as the lowest emissions of nitrogen oxides with flue gases (0.06 g / s). Further on these indicators there is the ecologically pure heat utilization installation, and the installation with KTAN-utilizer - KTAN - air heater is characterized by the lowest ecological and energy efficiency and at the same time ecologically pure installation has the same ecological efficiency