Comprehensive Benefit Evaluation Of Waste Heat Utilization Project In Glass Furnace

Glass industry is a typical kind of high energy consumption industry.In glass production lines,over 80%of the total energy consumption cost is fuel consumption,while 25%⁴0%of the total input calories of the fuel discharged into the atmosphere with the glass furnace flue gas.Smoke removal not only takes away a lot of residual heat resources,but also releases waste heat pollution and air pollutants such as SO₂,NO_x and TSP.Therefore,the reasonable utilization of flue gas waste heat can improve the thermal efficiency of glass furnace,and achieve the dual effect of energy saving and emission reduction.In this paper,the properties of flue gas waste heat of glass melting kiln and some kinds of common residual heat utilization system in glass factory are first introduce.The heat utilization of flue gas in glass melting kiln can be divided into thermal utilization and dynamic utilization.Heat utilization can provide steam,heating,cooling for glass works,and dynamic utilization can provide electrical power.In addition,according to temperature and cascade use principle,the heat utilization and power utilization can be integrated into a comprehensive heat utilization system,which can achieve the effect of providing cold quantity,heating and electricity at the same time.Based on the energy level analysis theory,when the proportion of heat utilization and power utilization is reasonably distributed,the whole system will achieve the best effect of saving energy.Secondly,this paper analyzes the energy-saving benefit,economic benefit,environmental and social benefits in this glass factory flue gas waste heat utilization project and preliminary build a comprehensive benefit evaluation model according to the system feature selection efficiency evaluation index.In addition,this paper introduces cases of two typical specification glass melting kiln?150t/d and 600t/d?waste heat utilization project,and gives comprehensive benefit evaluation respectively,based on the above evaluation model.150 t/d glass furnace uses the waste heat to provide heating,cooling,and steam.When the project put into practice,the comprehensive utilization of waste heat is 8.7%,saving standard coal 635 tons.The project financial internal rate of return is 12.4%,slightly higher than the benchmark.And the static payback period is 6.6 years by calculation.The environmental benefits of the project are analyzed,including the reduction of waste heat and atmospheric pollutants and the social benefits of the project.This paper summarizes the problems caused by the waste heat utilization system during the operation and provides reference for the design and operation of similar projects in the future.600 t/d glass furnace applies the combined system,which use waste heat to generate electric power and provide heat and steam.After the project put into practice,the comprehensive utilization of waste heat can be up to 39%?when burning heavy oil?,saving standard coal 7550 tons.The project financial internal rate of return reached22.4%and the static payback period is 4.2 years by calculation.At the same time,it analyzes the good emissions reduction effect of the project and the excellent social benefits.The influence factors of power generation of the waste heat system are summarized,and the effects of the second phase project on the comprehensive benefit are estimated.Finally,according to the analysis of the two sets of case indexes,the paper recommends the different applications of smoke utilization system for different specifications of glass melting kilns,and the way to improve the comprehensive benefit.This paper also points out the undoing of this thesis and the direction that need to be explored in theory and engineering practice.