Study Of The Operating Characterisitics Of Waste Heat Power Generation System Of Marine Main Diesel Engine

Ship transport consumes amount of energy. With the rising oil prices and the higher proportion of the fuel costs in transportation, how to reduce energy consumption effectively becomes a real and significant issue. Diesel engine is the most commonly used power device in marine. There are large amounts of available heat included in the exhaust gas, the jacket water and compressed air. If the available heat can be used to generate electricity or supply steam for the auxiliary equipment instead of the auxiliary engine and boiler, the fuel consumption and transportation costs will be reduced effectively.This paper introduced the main application of the waste heat and divides the appropriate utilization of waste heat adopted in a range of marine engines. Taking the 8530TEU engine as a research instance and according to the actual needs of ship bootstrap system and the comparative analysis of the composition, principle, advantages and disadvantages, and application scope of five kings of typical diesel engine waste heat power generation system,the suitable single and double pressure diesel engine waste heat power generation system was designed respectively, the system thermodynamic calculation model was set up and the operating characteristic of waste heat power generation system was studied in this paper.Taking the rated conditions of main diesel engine as the system design conditions, this paper calculated the heat balance for waste heat power generation system in single and double pressure system respectively, found out the characteristic parameters of each node under the design of system parameters, designed and selected the main equipment. On this basis,according to calculate the heat balance and analyze the operating characteristic of the single and double pressure waste heat power generation system in different working conditions, this paper investigated the change rule and influence factors of the all node parameters in different conditions. Through the contrast analysis of operation characteristic of single and double pressure waste heat power generation system, this paper let us better understand the merits and demerits of the single and double pressure system.Analysis results show that the highest heat power in single pressure system is 1726kW,but it is 2326kW in the dual pressure system. In theory, both of them can meet the normal electricity demand in the ship, and oil-saving rate are 2.47% and 3.33%. Energy saving benefit is obvious. With the reduction of the engine power, the node parameters, power generation of waste heat and the system parameters all show regular changes, the exhaust temperature and flow is the biggest impact factors. Under the same conditiors, Compared the single pressure waste heat power generation system with the dual pressure system can be found that a single pressure waste heat power generation system have a higher reliability and a lower cost of investment, dual pressure system have a larger power generation,higher oil-saving rate, and energy saving and economic benefit about power generation is remarkable.Analyzing the system characteristic of waste heat recovery can provide scientific basis for the selection of ship energy saving technology solutions and the development of waste heat recovery technology, point out the direction for ship energy saving. This is a great deal of help for making good use of all kinds of energy on the ship and comprehensive utilization of fuel level and reducing the pollution to the environment. Therefore, the significance of studying the characteristics of the waste heat recovery system is great.