粉煤灰在环境保护中的应用文献综述..doc

文 献 综 述 题目： Abstract：With the development of economy,energy consumption is growing, coal is increasingly becoming the main fuel in the world. Fly ash is one of the worlds largest industrial waste emissions at present, not only the serious pollution of the environment. At present, the total stockpile of fly ash in China has exceeded 10 tons, and is increasing at the speed oftons every year. We produce a large number of solid waste has brought tremendous pressure to the coal enterprises normal operation and the ecological environment, the national sustainable development strategy implementation will also have an important influence. Over the years, the world has conducted the thorough careful research to coal-fired power plant fly ash, has made many achievements, opening the way for its comprehensive utilization. The resources of utilization of fly ash is a major issue of economic construction and environmental protection, can be recycled to avoid waste and pollution of the environment but also for metals and minerals which can reduce the use of coal storage capacity. As the substitute of fly ash products, the products with high added value to indirect saving other mineral resource development. This not only makes the emission problem has been partially solved, as the source of new metal salts and provides a new way and has far-reaching significance. Keywords：Fly ash；Environmental Protection；Adsorption ; solid waste; fly ash to aluminum, iron 正 文 1.粉煤灰的基本介绍 1、粉煤灰，是从煤燃烧后的烟气中收捕下来的细灰，粉煤灰是燃煤电厂排出的主要固体废物。我国火电厂粉煤灰的主要氧化物组成为：SiO2、Al2O3、FeO、Fe2O3、CaO、TiO2等。粉煤灰是我国当前排量较大的工业废渣之一，随着电力工业的发展，燃煤电厂的粉煤灰排放量逐年增加。大量的粉煤灰不加处理，就会产生扬尘，污染大气；若排入水系会造成河流淤塞，而其中的有毒化学物质还会对人体和生物造成危害。另外粉煤灰可作为混凝土的掺合料 2.、粉煤灰的形成及特性 煤粉在炉膛中呈悬浮状态燃烧，燃煤中的绝大部分可燃物都能在炉内烧尽，而煤粉中的不燃物(主要为灰分)大量混杂在高温烟气中。这些不燃物因受到高温作用而部分在锅炉尾 部引风机的抽气作用下，含有大量灰分的烟气流向炉尾。随着烟气温度的降低，一部分熔融的细粒因受到一定程度的急冷呈玻璃体状态，从而具有较高的潜在活性。在引风机将烟气排人大气之前，上述这些细小的球形颗粒，经过除尘器，被分离、收集，即为粉煤灰。 粉煤灰中的矿物与原煤总的矿物有关，原煤所含矿物主要是铝硅酸盐矿物、氧化硅、黄铁矿、磁铁矿、赤铁矿、碳酸盐、硫酸盐、磷酸盐和氯化物