Research Of Dyeing And Printing Factory Energy Saving Project Based On Thermodynamic Analysis

The use of energy is not only related to the development of economy of the whole country, but also the level of social production and people’s lives. In the cases that our country is lacking in the per capita resources and the fossil fuels is Non-renewable and the development of new energy is limited, energy saving is becoming more and more important as a method to ease the source crisis. Before that, energy saving can’t be talking without the thermodynamic analysis of energy systems.Dyeing and printing industry as we know is one of energy-intensive industries. The boiler which provides steam also needs to consume a lot of energy. Along with the rising coal prices, the price of saturated steam stays high. The rising energy costs compress the profit margins of the enterprise further. The strategy of energy conservation and emissions reduction leaves the enterprise’s development awkward by facing severe challenges. Many enterprise start digging their potential by energy saving methods to reverse the situation.This thesis is based on the energy-saving renovation project of J dyeing and printing factory. Thermodynamic analysis of energy systems including energy balance analysis and exergy analysis are used to analyze the energy utilization conditions of the factory and its boiler systems. An energy saving and transform plan is made based on the analysis and it comes out with good energy saving effect. The main work and results of this thesis is as follows:1. Two thermodynamic analysis methods including energy balance analysis and exergy analysis and their theoretical basis, analysis models and calculation methods are obtained in this thesis. The former lays emphasis on the quantity of energy and the latter emphasizes both quantity and quality. The combination of these two methods can make a better understanding of the enterprise which needs energy conservation transformation.2. The energy balance analysis of J factory based on the heat efficiency calculations of its main energy-consuming machines shows that the energy utilization rate is really low. The energy utilization rates of the boiler, cylinder dryer, rapid steamer and setting machine respectively are 68.81% 62.33%, 19.4% and 29.5%. And the energy utilization rate of the boiler is really low which contributes to the whole factory’s rate of 27.88%. Problems in dyeing and printing process itself and waste of heat resources are the main reason to cause this situation.3. The exergy analysis of the boiler are had based on the energy balance analysis and heat efficiency test aims to find out the reason of low heat efficiency rate. The analysis result shows that the exergy efficiency of the boiler is 34.78% which remains a low level. The mian loss of the exergy of the boiler includs outer and inner loss and the inner loss which stands for the burnning loss and heat transfer loss makes up the main part.4. The energy saving and transformation plan is made to solve the problem the analysis shows which includes two main aspects: waste heat recovery,boiler transformation and exergy efficiency improvement. The design of the waste heat recovery system heats the boiler water from 25℃ to 75℃. The transformation of the boiler includes the transformation of the economizer, cyclone separator and wind system. The thermal efficiency of the boiler increases by 17.5% and exergy efficiency increases by 12% at the same time after the embodiment. The whole plan of energy saving project brings a more than 3.2 million Yuan profit to the factory per year.