【作者】 丁婷；

【导师】 邢国平；

【作者基本信息】 天津大学 ， 环境工程， 2009， 硕士

【摘要】 天津是中国最大的淡水极缺的海滨城市。利用海水淡化技术可以有效的解决天津市未来发展对水资源的需求问题。而渤海湾地区海水具有低温低浊度、有机物、胶体物质、悬浮物以及细菌等较其他海域高的特点,属于海水劣IV类水的水质。如此特殊的海水水质给反渗透海水淡化厂的设计建造带来了一定问题。反渗透海水淡化技术由于其设备投资省、能量消耗低、建造周期短等诸多优点,近十年来发展速度很快,未来将成为海水淡化的主导技术。从理论上讲,它是最节能的海水淡化方法。但目前,对于反渗透海水淡化,其技术经济指标和社会的期盼值之间,还存在一定的距离,淡化水成本仍偏高。因此,本课题在结合相关示范工程资料和天津地区海水水质的基础上,加入一定的预处理设备,计算所加设备给处理系统带来的能耗,并将其转化为具体的投资成本或运行管理成本,从而计算出该反渗透海水淡化系统总的造水成本。本课题通过分析,总结出渤海湾海域的海水水质特点,海水受到一定程度的污染,有机物及微生物指标较一般海域偏高,由于是半封闭海湾,而且动力条件有限,水体交换时间较长,营养性物质积累易形成局部富营养化。另外,还具有较强的腐蚀性和硬度。鉴于以上水质特点,必须加强反渗透海水淡化系统的预处理工艺。所以,要在其既有预处理设备之后加入超滤膜组件以降低水中SDI,冬季水温低时还要增加升温设备,以确保反渗透过程可以顺利进行。由于增加了设备和能耗,这样会给造水成本带来影响,通过计算和比较,得出造水成本由示范工程中的6.15元/吨产水提高到16.1元/吨产水。更多还原

【Abstract】 Tianjin is the seaside city in China that the situation of lack of freshwater is awfully serious. Taking use of the seawater desalination technology can effectively solve the problem of the city of Tianjin’s future development need for water resource. However, the seawater in the area of the bay of Bohai is characteristic of low temperature in winter and high turbidity, as well as, the index, as organic matter, colloid matters, suspended solid and bacterium, are higher than other sea areas. The seawater of this area is in class IV of low quality. The water quality of this area is so special that, to some extent, it brings problems of the designing and construction of the reverse osmosis desalination plant. Seawater reverse osmosis (SWRO) desalination technology has an rapid development in recent ten years, and it will become the primary desalination technology in the future because of its many advantages, such as less equipment investment, lower energy consumption and shorter construction period than other desalination methods. Theoretically, it is the most energy-saving seawater desalination method. However, at present the technical economical indicators of SWRO don’t reach the public expected value, and the cost of desalination is on the high side. And system energy consumption cost is the main component of the total cost, therefore, excessive energy consumption has become the most important factor of constraining the making water cost. It shows that the current SWRO system can be improved in some aspects, such as the SWRO technology, the engineering design, and the system operation etc. For this reason, on the base of the integration of the relational demonstration projects materials and the special seawater quality of this area, adding some pretreatment equipments, and then making calculations of the energy consumption of the treatment systems added by these equipments. Meanwhile, transform the energy consumption into specific investment costs and operation and management costs. By this means, making calculation of the total costs of building water in this seawater reverse osmosis (SWRO) desalination plant.The study used the reference of Demonstration project of SWRO in the town of Shengshan, Zhejiang Province. Through consulting the materials, summarize the characters of seawater quality of the area in the bay of Bohai. The sea water is polluted to some certain extent, the organic matters and the microorganism target common sea area is high; Because it is a half-seal bay, and with the limited dynamic condition, the water body exchange time is long, the trophism materials accumulate easily to form the partial eutrophication. Moreover, it also has the strong corrosiveness and degree of hardness. In the view of the fact of the above water quality characteristic, the need of strengthening the reverse osmosis seawater desalination system’s pretreatment crafts is necessary. Therefore, adding the ultrafiltration diaphragm module after the pretreatment in the system to reduce the SDI of the seawater is an essential step. Afterward, in the winter, when water temperature is low we must increase the elevation of temperature equipment in this system, to guaranteed that the reverse osmosis process may carry on smoothly.Because of the increase of the equipments and the energy consumption, it will bring some influence on the water cost, through the computation and the comparison, we will obtain that the water cost is enhanced from 6.15 Yuan/tons in the demonstration project to 16.1 Yuan/ton.更多还原