The Influence Of Different Heating Methods On The Indoor Environment Of Rural House-hold Building

At present,the mode of winter heating of rural single buildings in cold regions in China is mainly heated by Kang heating,wall heating,boiler heating and stove heating and so on.However,the traditional heating methods have caused the problems of poor thermal comfort and serious indoor air pollution in the heating room.With the development of the rural economy and the improvement of the people's living standard,people began to pay attention to the improvement of the quality of life.The clean and pollution-free solar energy heating system has been gradually applied to the heating in winter.There fore,it is necessary to understand the advantages and disadvantages of traditional heating methods and new heating methods in indoor thermal environment,indoor air quality and energy saving economy,and then provide important reference and theoretical gu idance for the selection of winter heating mode in cold area.From the aspects of indoor thermal environment,indoor air quality,economy and pollutant discharge of heating system s,this paper carries out a test study on floor Kang heating,overhead Kang heating,coal-fired boiler radiator heating and active solar energy low temperature radiant floor heating system.In the two continuous heating seasons from 2014 to 2015,a comparative test was carried out on a single building in Minqin County,Gansu Provin ce,using a coal-fired boiler radiator heating and active solar low temperature radiant floor heating.In 2016,a comparative experiment was carried out on two rooms in Lintao County,Gansu Province,with floor Kang heating and overhead Kang heating,respectively,with the same structure and orientation.The indoor and outdoor temperature and humidity,indoor and outdoor air velocity,inner wall temperature of enclosure structure and the vertical temperature distribution in indoor heating room are measured in this paper.For indoor air quality test research,this paper mainly measured the SO 2 concentration,CO concentration,CO2 concentration and indoor particulate matter concentration in heating room.In this paper,the system economy is mainly analyzed fro m two aspects of the system initial investment and operating cost,and the energy saving and emission reduction of the system is mainly analyzed from SO 2,CO,CO2,NOx,PM10 and PM2.5 emissions.The main results of this paper are as follows:(1)The research on indoor thermal environment under four heating systems shows that the indoor thermal environment of the solar heating system is obviously superior to the other three kinds of heating systems.The indoor temperature of a solar heating room is similar to that of a coal-fired boiler heating room,which is higher than the overhead Kang heating and floor Kang heating room.But the indoor vertical temperature of the heating room of coal fired boiler rises from bottom to top,and the temperature stratification is obvious.The indoor vertical temperature distribution is the best when the solar heating system is heating,and the indoor air velocity of the solar heating room is the lowest,and the relative humidity in the room is stable.(2)The indoor comfort evaluation of four kinds of heating systems shows that the indoor comfort of the solar heating system is best.Before the heating at 16:00 p.m.,indoor comfort is at grade II,and after heating,indoor comfort was raised to grade I from 18:00 to 7:00 in the morning of second day.The indoor comfortableness of the traditional Kang heating system and the overhead Kang heating system is the worst,and the indoor comfort level is grade III.The indoor comfort of the heating room of coal fired boiler has changed greatly,and the indoor comfort is better only in short time after coal entry.After 24:00,the indoor thermal comfort fell sharply to grade III.(3)The comparison of indoor air quality under four kinds of heating systems shows that the indoor air quality under solar heating is the best,grade II level,the indoor air is not polluted.The indoor air quality of coal-fired boiler heating is grade IV,which is moderate pollution,and the content of indoor particulate matter is seriously exceeding the standard.The indoor air quality grade of the traditional floor Kang room and the overhead Kang room is grade V,heavy pollution,and the content of PM10 and PM2.5 seriously exceeds the standard.(4)The economy and pollutant discharge of different heating system s are compared and analyzed.In the four heating systems,the traditional floor Kang and the overhead Kang have the lowest installation cost s.The installation costs of coal fired boilers are second,but the cost of operation is high.While the solar heating system has the highest installation cost,compared to coal-fired boiler heating system,the investment recovery period of solar heating system is only 2.9 years.The traditional floor Kang heating system,the overhead Kang heating system and the heating system of coal-fired boiler emit a large amount of carbon oxide because the fuel is coal and firewood,.Solar heating system using solar energy which is clean energy,and non-pollutant discharge during operation.Compared with other heating systems,the energy saving and emission reduction effect of solar heating system is obvious.The innovation of this topic lies in:In this paper,four kinds of heating methods for the winter heating of single buildings in Northwest China are summarized.this paper compr ehensively evaluates the influence of different heating modes on the indoor environment of a single building,and the economy and pollutant discharge of different heating modes are compared and analyzed.