Study On The Marine Ship Waste Heat Recovery System Based On The Matrix Mode Thermo-economic

The fuel cost account for the proportion of the ship transport cost has become increasingly high with the international oil price rise rapidly. At the same time, in order to alleviate the greenhouse effect, reduce CO2 emissions, MEPC meeting formulated and adopted a resolution on the EEDI, and saving energy and reducing emission have become an inevitable trend in the development of the shipbuilding industry.Firstly, through analyzing of the status of the development of marine diesel engine waste heat utilization at home and abroad, installing waste heat recovery system for ships can effectively reduce the loss of energy because of the diesel exhaust and cooling water, and improving the overall energy efficiency of the ship. We can get its deeper causes of energy loss by using the thermodynamic point and complete the calculation of the system's cost through analyzing the contents of the thermo-economics, and combining the relevant theory with marine diesel engine waste heat recovery systems. It provides a more profound guidance for optional of the waste heat utilization system while studying the ship's main diesel engine waste heat utilization system from the energy and the cost.Secondly, this paper takes MAN B&W 6S50ME for the host diesel engine of the waste heat utilization system as an example. According to the relevant knowledge of classical thermodynamics, establishing the exergy balance model of the major equipment of ultra-low temperature waste heat utilization system based on the exergy analysis of the thermodynamic process of the stable flow open system. We can conduct comprehensive energy and exergy analysis of the marine diesel engine waste heat utilization system with the concept of exergy analysis method, getting the result of the heat exergy losses,exergy efficiency and other parameters of the main components of the system, and getting the rules of the loss of exhaust and cooling water of the diesel engine with the variation power of main diesel. In addition, we calculate and analysis the two-stage double-pressure waste heat power generation system and the system which installed an ORC part. As a conclusion, the ORC power generation system can effectively utilize waste heat to generate considerable power, the results showed that: the system fuel has the highest efficiency when the host between 75% to 85% load, and drawing the conclusion that the waste heat boiler, dual-pressure steam turbines and air coolers and other equipment are the key part to thermodynamic optimization.Lastly, we draw a marine diesel engine waste heat utilization system block diagram that applied to the matrix model of thermal economics by studying on the matrix model of thermal economics theory, through making sure the "fuel" and "product" of system, establish fuel event matrix and product events matrix, and establish supplementary equation. We get the exergetic cost and unit exergetic cost of each flow of the waste heat utilization system and subsystem by using Matlab software to solve the matrix, and calculate the four typical operating conditions, ie 100% of the host load, 85% load, 75% load, 50% load, and get an conclusion that the unit exergetic cost of each flow of system is decrease with the drop of host diesel engine power. Because the air cooler and jacket water cooler have external heating, and therefore we take the external heating as different external pricing, which analyzed the different external pricing impact on exergetic cost of the system. Finally, analyzing the thermal economics of marine waste heat utilization system combined with the quotation of each device and get the lower unit thermo-economic cost at the 85% host load.This paper obtained the rules of marine power system energy use, transfer and loss, and pointed out the key events of marine diesel engine waste heat utilization system energy conservation research through modeling and calculation of the marine diesel engine waste heat utilization system, and lay a theoretical foundation for the development of efficient ship host engine waste heat utilization system. It can analyze the actual cost and make decision by studying on the marine ship waste heat utilization system based on the matrix mode thermo-economic,and provide a more profound guidance for an actual project.