气体混合炉中氧逸度控制

氧逸度是影响地质体系性质的物理化学变量之一。实验岩石学中常利用氧逸度可控的气体混合炉进行设定氧逸度下的实验。常用的混合气体组合包括CO_2-CO、CO_2-H_2和H_2-H_2O体系。然而,混合气体配比涉及到的较复杂的热力学计算以及老旧的热力学数据阻碍了该项技术在实验岩石学中的应用。本文根据新的物理化学数据,对不同混合气体体系(如CO_2-CO,CO_2-H_2和H_2-H_2O)温度-氧逸度-气体混合比例关系进行了重新计算和评估。另外,还计算了O_2-惰性气体、CO_2-O_2和H_2O-O_2体系,弥补了前人CO_2-CO、CO_2-H_2和H_2-H_2O体系不能控制高氧逸度(大于CO_2体系)的缺陷。最后,比较了应用新旧不同热力学数据库算出的结果,认为随着基础物理化学数据的不断更新,温度-氧逸度-气体混合比例关系也应不断更新。

二次风分布对CFB锅炉炉内气固混合及燃烧的影响

对于循环流化床锅炉,通常是将总风量分为一次风和二次风来控制燃烧过程的进行,而大型循环流化床锅炉又进一步将二次风沿炉膛高度方向分为若干层并分布在燃烧室四面墙上来加强对燃烧过程的控制。首先介绍了横向二次风射流对促进循环流化床锅炉气固混合及煤燃烧的作用。在一台燃烧低挥发分煤的循环流化床锅炉上进行的实验,分析炉内流场对该锅炉不同供风模式下二次风在炉内分布情况的影响。在此基础上考察二次风在炉内不同的分配方式对煤的燃尽和炉内温度场的影响。实验结果表明,通过二次风优化可以加强炉内气固混合,促进气体和燃料的扩散,提高燃烧低挥发份煤的CFB锅炉燃烧效率。

Heating and Cooling Hybrid System with Gas Mixture Sourced Heat Pump and Heating Boiler

Preliminary investigation shows that air sourced type heat pumps by energy efficiency are competitive with gas boilers having 93% of coefficient of performance （COP） if heat pumps are used in climatic zones, having outside air temperature higher than （-3 ℃ to -5 ℃）. But, in such conditions the heat pump＇s evaporator is covered by ice crust, which cuts off the flow of outside air-heat source through the evaporator of heat pump. For avoiding stating problems it is recommended to use as heat source a mixture of waste warm gases. In this article a high efficiency heating-cooling system is developed, consisting of warm gases mixture sourced heat pump, heating boiler operating simultaneously with heat pump and solar air heater. The heating demand of the served house is shared between boiler and heat pump. Instead of outside air the warm gases mixture enters into evaporator of heat pump. A new construction of heat exchanger was developed. The article presents the structure and principle of operation, as well as the method for optimization and design of suggested system. Analysis proved high energy efficiency and cost effectiveness of the new system.