【作者】 胡艳英；

【导师】 王述洋；

【作者基本信息】 东北林业大学 ， 机械设计及理论， 2012， 博士

【摘要】 在我国北部沙漠边缘地区,有丰富的沙生灌木资源,这类植物对当地盛态环境保护具有重要意义。沙生灌木有一重要生长特性,在生长3-5年后,需进行平茬复壮,这样才能保证其更好的生存、生长,否则将导致大面积枯萎死亡。由于平茬作业要求高且没有经济收益,在当地几乎没有人愿意从事这项工作。沙生灌木平茬剩余物是很好的生物质资源,若能采用生物质直燃发电技术对其充分利用,不仅企业能获得经济收益,还会给当地农民带来经济收益,同时使沙生灌木获得大面积存活、生长的机会,可谓一举多得。然而在实际操作中,已投资的沙生灌木发电项目并未获得预期利润,其中一个很重要的原因是集料处理成本过高导致发电成本大于发电价格,企业不能生产运营。本文就沙生灌木发电集料处理机械作业系统进行优化研究,以期找到最小成本下的最优工艺路径。针对集料处理机械作业系统中各工序步的作业时间和作业顺序问题,本文基于沙生灌木含水率测定试验进行研究,通过对不同环境、不同处理方式下的灌木平茬剩余物含水率下降速度进行测试,得出主要工序步的作业时间段和作业顺序,从而确定了作业系统的工序步作业起止时间和工艺路径框架。针对工艺路径优化问题,本文采用机械系统优化理论和大系统理论,对沙生灌木发电集料处理机械作业系统实施先分解后协调的研究方法,首先对各子系统进行功能分析和设备选型,然后对各子系统的工艺成本进行算法设计,最后结合实例进行综合计算,检验各算法并对算法进行修正。通过研究得到了最低工艺成本下的最优工艺路径和最小工艺成本,并在研究过程中实现了现有设备的选型、创新、改良。结合计算机程序辅助设计手段,本文基于遗传算法对作业系统进行了优化程序设计,针对所有可能的工序组合进行了全局搜索,最后获得了最小工艺成本下的工艺路径。由于集料处理作业系统属于发电作业系统的一部分,仅对集料处理作业系统的优化尚不能保证发电项目实现赢利目标。文章采用模糊评价法构建了生物质发电项目的评价体系,只有通过评价体系相应评级标准,其集料处理作业系统优化才具有现实操作意义。通过上述研究可知在当前人力资源成本、设备成本、运输成本条件下,沙生灌木集料处理作业成本可降至合理水平,能够实现当前电价下获取利润的目标；通过优化设计获得的工艺路径在实例中操作可行,可进行推广；在研究中创新设计的平茬—切断一体机可节约27%左右的集料处理成本,建议进行更深入细致的研究；以模糊评价法构建的生物质评价体系通过实例验证能推广使用。沙生灌木发电项目是我国刚刚兴起的生物质项目,它的推广对于企业获取经济效益、建厂区域获得良好社会效益和环境效益都有重要作用,希望通过本文研究能够对沙生灌木发电项日推广应用起到有益的作用。更多还原

【Abstract】 There is plenty of desert shrub at the edge of the desert in north China, which makes a significant sense of protecting local biological environment. being an important growth characteristics, desert shrub must be stumpped during3-5years which could make shrub survive, otherwise desert shrub will die in large area. Because shrub cutting work costs more and yield less profit, only few people are willing to work on this business.Residues of desert shrub after cutting process becomes a kind of good biomass resource. If it can be efficiently utilized, it will bring the users enormous benefit. Meanwhile, utilization of desert shrub can not only create economic profit for enterprises and local farmers but survive the desert shrub which can grow continuously protecting the local environment.In fact, however, such kinds of projects have not gained expected economic benefit, the main reason is high running cost. High cost of shrub cutting, collecting and processing, which results in high cost of running, leads to a higher generation cost,so the generation factory can only supply power to the users at the higher price than current market power price.This paper on optimization of desert shrub collecting and processing operation system will focus on this matter, which will help to find the optimized process path at the least processing cost.In order to improve the process arrangement of processing time and sequence in desert shrub cutting collecting and processing operation, lots of tests have been undertaken on the basis of various testing condition of changing moisture, different environment and different processing ways. As a result, this paper draws a conclusion of defining the start-stop time of processing steps and the framework of process path.In accordance with mechanical system optimization theory and large scale system theory, the analytical and study method-"first to decompose, then to coordinate " is used to solve the problem of process path optimization. Process path optimization contains three steps, firstly, analyzing sub-system function and choosing the equipments; secondly, giving algorithm designing on process cost of sub-system, thirdly, calculating the case, testing and amending the arithmetic, As a conclusion, we obtain the optimized process path on the condition of the least process cost, meanwhile reform and improve the machines being used.This paper achieves in optimizing the desert shrub cutting collecting and processing operation system. By means of Genetic Algorithm Method and with the help of CAD(Computer Aided Design), the paper analyze all possible process step mixtures and obtain the best process path.Comparing with the optimization conclusions drawn through different methods, we find that the results are unanimous, which testifies that the study is in right direction.Desert shrub collecting and processing optimization is a part of biomass generation system, partial optimization can not support the integrated optimization for the purpose of gaining profit. In the last chapter, an evaluation system on basis of fuzzy evaluation method is established. This evaluation system, particularly including relative evaluation rating criterion, makes the desert shrub collecting and processing system optimization feasible and practical.There are some conclusions in this paper.First, under current conditions of various cost of human resource, equipments and transportation, if we can reduce the cost of desert shrub collecting and processing to reasonable level, we will achieve our goal of gaining profit,Second, the empirical optimized process path can be used by and popularized to more users. The new designed cutting and chipper all-in-one machine can reduce the cost of processing by27%. This newly-designed machine lays a foundation for further study.And then, the evaluation system on basis of fuzzy evaluation method, is evidenced by empirical cases to be used in more users.Desert shrub biomass generation has been developing only for the recent years. This kind of project is very important for the enterprise to obtain profits and for local government to obtain social benefit and environment benefits, and the projects can be popularized and applied widely. the writer hopes that the paper will be helpful for popularizing desert shrub biomass generation projects.更多还原