粉煤灰改性处理SO₂、含铅废水有害物的研究

【作者】 李方文；

【导师】 魏先勋；

【作者基本信息】 湖南大学 ， 环境工程， 2002， 硕士

【摘要】 我国是世界上最大的产煤国和耗煤国，燃煤占了我国能源结构的70％。1990年产生的粉煤灰达8000万吨，到2000年已达1． 6亿吨，为处置这些粉煤灰而建的储灰场占据了大量的土地与消耗了大量的水，且目前我国粉煤灰的利用率只有30％，大部分集中在建筑材料方面。因此，怎样处置粉煤灰、提高它的利用率对我国而言是一个重要的问题。本文针对湿法脱硫中存在的缺点，意图通过粉煤灰改性来研制干法脱硫剂，用于干法脱硫。这样，一方面可以开辟粉煤灰新的利用途径，从而提高粉煤灰的利用率：另一方面可以开发新的脱硫形式，寻求适合我国国情的脱硫方法。我们用煅烧--碱溶法研制出具有类4A沸石结构的改性粉煤灰A来吸附低浓度二氧化硫，结果显示改性粉煤灰A对低浓度二氧化硫的吸附容量、脱硫率100％维持的时间只有4A沸石的10． 98％、1／20，没有达到预期的脱硫效果。为此，我们又改用了另一种方法(煅烧--消化法)来改性粉煤灰，得到改性粉煤灰B，并用它来处理低浓度的二氧化硫，实验结果表明：它对低浓度二氧化硫具有很好的效果，脱硫率100％的维持时间为70分钟，吸着容量为133． 00mg／g，钙的利用率为70． 76％，比常见的干法脱硫的钙利用率提高了近20个百分点，压降为8． 33Pa／cm。另简要地研究了改性粉煤灰A的离子交换性，并用它来处理含铅废水，结果表明它对含铅废水有良好的去除效果。更多还原

【Abstract】 Our country is the biggest country of producing and consuming coal in the world,and the burned coal occupies 70% of our country energy construction. The emission offly ash in l990 was 8 millions tons, and by the end of 2000 the amount of fly ash hadreached 160 million tons. To deal with these fly ash, the builded field of storing fly ashhas holded a lot of land and consumed much water. At present fly ash is used only 30percent in our country; further, most of the used fly ash lies in the field of constructionand stuff. Therefore, it is an important problem for our country how to handle fly ashand heighten its utilization. This text intends to develop dry desulfurizer and desulfrizeby the means of changing fly ash at aim to the weakness of the wet method ofdesulfrize. Like this, on one side the new use approach is to be developed, which canheighten the utilization rate of fly ash .On the other side the new fOrm of desulfrizer isto be explored, which can look for the desulfrize ways to adapt to the situation of ourcountry. We manufactured the changing qua1ity fly ash A like the structure of 4Azeolite with the method of calcinations-alkali and treated with the low thicknessSOz.The experimental resu1t proves: the adsorptive capacity and the desulfrize rate ofl00% are respectively 10.98%. l/20 of that of 4A zeolite, and do not attain toanticipative desulfrization effect. For this, we changed fly ash by the other method (thecalcinations-digest), and achieved the changing quality fly ash B.We disposed of thelow thickness SO2 with the fly ash B.The experimental result proves: the effect is quitegood, and it is 70 minutes that the rate of desulfurization keeps up 100%, andabsorption content achieves l33.00mg/g, and 70.76 percent of calcium are used .Theutilization rate of calcium drops 20% than that of usual dry desulfurization and the fallof press is 8.33Pa/cm. Additional, we briefly studied the ion-exchange character of thechanging fly ash A, and disposed of the waster water containing of lead, and the betterremoval result was gained.更多还原