1、本科毕业设计（论文） 外 文 翻 译 原文 ： Understanding mine site water and salt dynamics to support integrated water quality and quantity management Water reuse is becoming an integral component of the water management strategy on mine sites. This practise is being driven by corporate sustainability goals, community
2、 and societal pressures to demonstrate improved water stewardship, as well as climate and regulatory pressures. However, water reuse often results in water quality compromise which can then result in decreased recovery through problems in processing circuits, product quality, and an increased likeli
3、hood of discharge of water that cannot meet environmental regulatory requirements. On most mine sites, there is usually a disjuncture between water quantity management and water quality management with the latter being managed solely as an environmental problem. It is becoming increasingly clear tha
4、t water quality and quantity must be managed as an integrated system. In order to integrate water quality and quantity management to achieve multiple objectives the dynamics of water and constituents must be understood. Using examples from a study being conducted at a coal mine the Bowen Basin, this
5、 paper will outline the dynamics of water and salts on the site. Introduction The need for sustainable water management practises is being driven by corporate sustainability goals, increased public scrutiny of water use, management, and environmental stewardship, the relative economics of increasing
6、 reuse against the alternative of increased supply of fresh water and climate conditions. The ability to simultaneously meet water quantity, water quality and product quality objectives is becoming an increasingly challenging component of water management on mine sites. However, because the water sy
7、stem on a mine site acts as a complex system with feedbacks and interactions between the natural climate driven system and the engineered reticulation there are often unintended impacts from water management decisions that only consider one set of objectives In the coal industry, there has been cons
8、iderable investment in improving water management on sites. This has been driven by widespread and prolonged drought as well as corporate targets for freshwater savings. Over the last decade most sites have adopted water reuse as a means for making freshwater savings. However, water reuse results in
9、 increased salinity in site water stores (Moran et al, 2006). The increase in salinity is driven largely by evaporation and ongoing salt inputs from spoil, coal and groundwater. Effective management of dissolved salts can provide opportunities for reducing risks and costs in managing water and the e
10、nvironment, processing efficiency, product quality and operating/maintenance. In order to manage both water quality and quantity in an integrated system to meet multiple objectives on coal mines requires an understanding of the nature and sources of salts； the dynamics of the salt fluxes on a site；
11、and the impact of water quality on production and product quality. These factors must also be balanced against the risk of non-compliant discharge. The aim of this work was to increase understanding of the mine and climate conditions that result in salt fluxes from various parts of the site into the
12、 mine water reticulation system. With this information, operational guidelines can be developed that allow sites to proactively, rather than reactively manage the water system to meet multiple objectives. This paper will present data that illustrate the responses of representative water bodies on th
13、e sites to changing climatic conditions. Previous modelling of water and salt fluxes has assumed that salts behave conservatively, ie that salt concentration of a water body will only change in direct proportion to the mixing of input waters with different salt concentrations (eg Moran et al, 2006).
14、 While this is a generally acceptable assumption for predicting total salt concentrations and the overall implications of water management strategies, many individual ions comprising the salt load may participate in biogeochemical reactions which may dramatically alter the ion composition of a water
15、 body. This altered ion composition may have impacts on particular processes. For example, it is known that divalent cations (Mg and Ca) provide greater flotation benefits during coal washing than monovalent cations (Ofori et al, 2005). Thus it is important to not only understand the dynamics of tot
16、al salts on a site but also the principal processes governing the concentrations of individual ions comprising the salts. One of the difficulties in understanding the dynamics of water and salts on mine sites is that it is difficult to distinguish between water from different sources and therefore a
17、ccurately attribute salt fluxes. Inputs from a number of water sources, eg groundwater, run-off, etc cannot be metered. In this work stable isotopes Oxygen- 18 (denoted d18O) and Deuterium (denoted dD) have been used in conjunction with geochemical signatures to trace inputs from these unmetered wat
18、er sources 6 Times series of cation (top) and anion (bottom) concentration changes determined in surface waters of PitF. Average (z1 sd). Deep water concentrations are shown for comparison 7 Cation (top) and Anion (bottom) composition of run-off from spoil and road Run-off composition Although run-o
19、ff from spoil is not a large input to Pit F due to the small catchment area, the contribution via this process appears to impact the surface water ion composition as discussed below. This process may have a more pronounced impact on the water quality of water stores with larger catchment areas or areas with highly active spoil. Changes to rainfall composition during runoff from spoil and
