Mechanism And Integration Of Multi-functional Energy System With Multi Fossil Fuels And Multi Products

Synthetically combining the power generation, the chemical production and environment protection is one of the trends and characters of the development of energy science. The multi-functional energy system (MES), which has been considered as a sustainable energy system, can utilize multi energy (fossil fuel and renewable energy) synthetically and efficiently based on the system integration and the process innovation. Supported by the Nation Key Project (G1999022302) and the NSF of China (90210032), this research is to propose a new approach to utilize the natural gas and coal synthetically and reveal the internal phenomena during the energy conversion, to develop a new exergy analysis tool to analysis the new energy releasing process, and to proposed a new multi-functional energy system with advantage features.A new approach, named as dual fuel reforming is proposed to utilize the natural gas and coal synthetically, based on the analysis of the characters of the natural gas and coal. The new method integrated the processes of methane/steam reforming and coal combustion. The dual fuel reforming process is researched by making use of the energy level, and energy level equations, which describe the energy conversion, is obtained. The cascade utilization principle of chemical energy and physical energy of natural gas and coal during the dual fuel reforming is revealed and the features are investigated.A new exergy analysis method is developed based on the concept of energy level. The energy level equations of the complex energy conversion process are establishedand the principle of energy conversion and utilization in this process is revealed. Then the interactions between the processes are studied by combining the energy level equations. At last the essentiality of cascade utilization of chemical energy of fossil fuel is revealed.A new power plant integrated the dual fuel reforming process is proposed, in which the syngas generated by dual fuel reformer is sent to a gas turbine as fuel and the steam extracted from a steam turbine is provided to the dual fuel reformer. On the basis of simulation of the system, the thermal efficiency of coal to power can reach nearly 48%.Based on the dual fuel reforming process, a novel poly generation system is proposed. The new system integrates the dual fuel reforming process, the power plant and the chemical production system. The chemical energy of syngas is cascade utilized with the synthetic utilization of natural gas and coal. Based on the principle of ascade conversion of material according to composition? a part of syngas that suites for chemical production is used in the chemical process and the other is provide to gas turbine as fuel. Compared with the baseline systems, the performance of the new system is improved distinctively and the energy saving ratio is near 13%.Recent years, decreasing the low temperature of the thermal cycle and cascade utilization of chemical energy has been considered as a new way to improve the performance of thermal cycle. A new O2/CO2 cycle integrated the absorption refrigerator is proposed. The thermal energy at low temperature level is recovered by the absorption refrigerator and the cooling energy is used to liquefy CO2. A combined cycle with cascade utilization of chemical and cryogenic energy of LNG is integrated. The CRGT cycle is improved making use of energy level and the thermal efficiency is increased by 8 percentage points.