| At present,the main power generation methods in our country are hydroe-lectric generation,wind power generation and thermal power.The energy of thermal power plant comes from coal which is non-renewable resource.There-fore,it is necessary to improve the utilization of coal.Since 2013,fog and haze weather appears in a wide range of our country,especially in the northern in-dustrial developed area in where the fog and haze weather is more serious.Coal-fired power plant is one of the main causes of environmental pollution.In order to reduce the pollution to the environment,it is necessary to denitrate the tail gas at the end of the boiler.For the moment,there are two main methods of denitration:Selective Non-Catalytic Reduction(SNCR)technology and Selec-tive Catalytic Reduction(SCR)technology.Selective Non-Catalytic Reduction denitration technology requires the temperature of denitration area is about900℃,which results in that the temperature detection of the region is particu-larly important.Based on the infrared radiation temperature measurement principle and the analysis of the boiler combustion,this paper used the infrared temperature measurement technology to measure the boiler’s temperature,reconstructed the temperature field of the boiler,deduced boiler temperature field reconstruction algorithm,designed and developed a set of the boiler temperature detection and temperature field reconstruction system based on infrared radiation temperature measurement technology.Boiler of the transverse plane area is divided into a number of pixels on average,and we supposed that the average temperature of the pixel area is equal to its center point temperature.Then,we calculated the average temperature of the pixel area according to the infrared thermometer data.We used the MATLAB,which is an engineering mathematics software,to build the two dimensional temperature field of boiler according the spline in-terpolation method.The infrared thermometer of infrared temperature measur-ing system and communications systems were installed on the boiler level cross section.The PLC receives the measurement results of infrared thermometer and transmitted it to a computer.The computer to complete the reconstruction of the cross section temperature field of the boiler and scented the results to the PLC controller.The infrared temperature measurement system were used to detect the temperature and establish the two-dimensional temperature field of the Ruigua-ng power plant 2~#boiler when it in the full load condition.We calcu-lated the average absolute error,which is 31℃between the theory of tempera-ture and the tempura of measured.The maximum relative error is 6.4%.The minimum relative error is 6.4%.The average relative error was 2.2%.When boiler at 80%capacity,the temperature of the measured data and the infrared temperature measurement system reconstruction of temperature field are also conforms to the"core temperature is highest,gradually to reduce"of the boiler temperature field distribution characteristics.The double peak temperature field occasionally appeared in the process of boiler temperature detection.This paper analyzed the characteristics of double peak temperature field,and the reason of it appeared.Through the analysis of test results and error evaluation,we veri-fied that the infrared radiation temperature measurement technology can be used to detect the boiler temperature,and the validity and feasibility of two-dimensional temperature field reconstruction.That provides reference for in-depth study in the future. |
