Advanced Materials Research Vols. 953-954

Abstract: Based on the simulation of the air conditioning construction dynamic load and simulation calculation of air-source gas engine-driven heat pump (GEHP), the air-source GEHP air conditioning in winter, summer and the annual primary energy ratio are analyzed in simulation with the combination of a hotel building in Tianjin. Firstly, DeST software is used to simulate all-year hourly air conditioning load of the building. Then air-source GEHP simulation model [1] is used to calculate the annual hourly gas consumption and the amount of GEHP's gas consumption in winter, summer and a total year afterwards can be got. At the same time, by the analysis of waste heat recovery of gas engine-driven, primary energy ratio for air-source GEHP in Tianjin is given under the different waste heat recovery of winter, summer and the annual.

Abstract: For two practical engineering case in a University in Guilin, this paper mainly introduces the performance of sewage-source heat pump and ground source heat pump and compare the running status in two kinds of system. The studies have shown that the sewage source heat pump unit COP at about 3.9, the system COP at about 3.3, ground source heat pump unit COP at about 4.5, the system COP at about 3.4.

Abstract: The boundary element method was introduced to calculate the thermal resistance between pipe outside surface and the borehole inner surface of vertical U-shaped pipe underground heat exchanger. The effects of U-tube diameter, borehole diameter and tube spacing on the thermal resistance were also discussed. The results showed that it took only 10 min to complete a simulation of an underground heat pump running continually for 1000 h, which took least 3 h to complete the same cycle through finite volume method. When the thermal conductivity λ of the backfill material was 1.8 W/m²·K, the thermal resistance of the U-shaped pipe decreased with the increase in the tube spacing, it decreased with the increase in the U-tube diameter, however, it increased when the borehole diameter increased.

Abstract: This paper has studied using steam injector to recycle waste steam emission from autoclave kettle and it will produce great economic benefits and environmental benefits. Autoclave kettle which is a kind of resistance to high temperature high pressure steam curing equipment, and it’s mainly used for pipe pile, lime-sand brick and aerated concrete production. We will get more technical and economic benefits, if the research results can be popularized and applied in the national building materials products production.

Abstract: This review summarizes the research status of LNG including bulk usage status of LNG, fire risk in transport or storage, research work and progress about the behavior of LNG spills; rollover; pool fires; and explosion. The paper analyses the LNG widespread bulk usage trends in application as a new type of energy and discusses its characters and the further understanding about the security in using LNG.

Abstract: Natural gas is an important energy of national economy, and its security is tightly connected with industrialization process. A comprehensive security evaluation index system, including three first class indicators, eight second class indicators and twelve third class indicators, was created based on the pressure-state-response (PSR) model. Grey correlation analysis was adopted when calculating index correlation coefficient and entropy method to obtain the weight. By studying the data of China’s natural gas from 2001 to 2013, a comprehensive security index of China’s natural gas was got. The results showed that the comprehensive security index of China’s natural gas rose from its low point. The security pressure state of China’s natural gas was improved, the security state varied greatly, and the response state continued to rise. The overall situation of China’s natural gas security was not stable.

Abstract: The mechanism of NOx formation in coal combustion, NOx control methods and key DeNOx technologies is to be introduced. Denitrification is very significant for saving energy and carbon sources. By analysis of NOx production mechanism, the principles of controlling NOx production and lowering emission of NOx by classified combustion are described. Combined with actual operation, low-NOx combustion rehabilitation programs and relevant test to be done is to be proposed. The actual operation of the unit achieved good results after the transformation, provide a reference for similar units.

Abstract: With the continuous development and utilization of Marine resources, the island’s developments get more and more attention of the state, however, the island's power supply is always a bottleneck restricting the development of its economy. Microgrid as a kind of effective supply and use of distributed generation of power system, provides an effective solution for remote island power supply. There is a big difference in output characteristic from the power system, for the distributed power mostly use power electronic interface, which provides barriers to the protection of microgrid. The paper first introduces the structure and control mode of island microgrid based on wave energy power and currents can power generation, energy storage power, then analyzes the fault characteristics of the microgrid under different control, lastly summarizes the existing two types of microgrid relay protection method: the traditional overcurrent protection method and digital network protection method based on the communication.

Abstract: Coal-fired power units show defects in meeting the demands of maintaining power system frequency stability. This is mainly due to their inherent characteristics and a continuous increase in renewable generation. Battery Energy Storage System (BESS) has such advantages as fast response and precise tracking, thus may be a new frequency regulation method. On basis of the principle of energy storage for regulation, capacity configuration of energy storage is made as an alternative to coal-fired power unit accounting for both primary and secondary frequency regulation. Example calculations and simulation in MATLAB/SIMULINK are conducted to verify the feasibility of the proposed capacity configuration methods and the reliability of the energy storage system for regulation.

Abstract: This document researchs on 55kW GSHP black start based on 250kW/250kWh battery system and 50kW/10s super capacitor. The modeling methods of asynchronous motor, battery system, super capacitor and PCS are given. According to three black start conditions: direct start, star delta start and frequency conversion start, simulates and analyses the results. During black start, the max AC bus voltage drop reaches 60%, and hybrid energy storage system is able to effectively inhibit the inrush current.