Technological-economical Research Of External Combustion Stirling Engine With Combined Heating And Power Based On Biomass Gasification

Energy is the basis to the survival of mankind, and it is currently one of the most important problems of the world. How to develop and utilize resources are currently focused the world's attention. Biomass energy is the "the fourth energy" following after coal, oil and natural gas, and its use is increasingly being everyone's focus. How to use it efficiently is current research focus, so biomass power generation is the concentration of the current world energy research.China is a large agricultural country, rich in agricultural biomass, and most of them are the straw. The current biomass power generation technology divides into biomass direct combustion power generation technology and biomass gasification technology, both of which have some problems that restrict the biomass power generation technology to promote the application further. Straw gasification power generation technology such as surviving in the high gas vaporized tar content and low calorific value, this thesis presents a straw gasification Stirling Engine co-generation system. The system is built on the concept of energy cascade utilization, it can make full use of biomass energy, reduce the use of fossil fuels. And it is with energy efficiency, high reliability, environmental protection, load shifting and other advantages. Currently, straw gasification power generation technology is more to the internal combustion engine as a prime mover, it has not yet been proposed and studied outside the gas turbine as the prime mover system.Firstly, this thesis compares biomass direct combustion and gasification power generation technology. And then, internal and external combustion engine technology characteristics are analyzed. After that, this thesis puts forward the concept of straw gasification external combustion engine co-generation systems, including classification system, composition and performance evaluation forms, etc. Then, this thesis uses 10000 m2 in North China as object of study, and proposes system solutions. In addition, technical, operational, energy-efficiency and economic analysis, and analysis of the percentage of annualized costs are presented.For the office building, this thesis puts the Stirling Engine program, inner combustion engine programs and sub-programs for comparison, and presents the economic impact on price of straw. For the case in this thesis, straw gasification Stirling Engine co-generation system is more economical than internal combustion engine and thermal sub-program for the program. When the straw briquette price is lower than 690.65 yuan / t, the external combustion machine is the optimal solution.Finally, by using best annual earnings as object, this thesis establishes the mixed integer nonlinear programming optimization model to optimize straw gasification Stirling Engine co-generation system operation optimization, and analyzes the results of optimization. Optimization results show that: co-generation systems generate electricity at full capacity is the most profitable system, and the system's static payback period is 7.61 years, which shortens the payback period of nearly two years comparing with the original static system.