板式换热器经济性优化研究

针对板式换热器选型利用经验估算准确度低,利用软件Access 2010建立板换数据库和Visual Basic 6.0等工具开发了热工计算软件。在利用热平衡计算、传热计算和校核计算为主要数学模型基础上,增加了价值型评价方法。文中重点介绍了价值型评价方法,具体分析了初次投资费用和后续运行费用。结合实际算例,利用开发的软件选择满足热负荷以及压降的板式换热器,得到型号为E100-AF-MH的换热器换热面积最小,型号为BR0.4B的换热器总费用最小。结果表明换热面积与总费用不一定同时最优。文中所用的选型方法结合软件提高了选择效率,考虑用价值型评价方法选出了费用最少的型号,可节约成本、提高经济效益。

Study on the rights and interests value of mineral resources and its evaluation method

The rights and interests value of mineral resources includes the prospecting rights value and the mining rights value. The mining rights value is made up of the min-eral resources value and the compensation value based on the inputs of capitals and labors in different exploration stage, the prospecting rights value should be equal to ex-ploration differential rent of resources. According to the stage characteristic of mineral resources exploration and development, the initial evaluating methods and models are used to evaluate the prospecting rights and mining rights value.