【作者】 樊红辉；

【导师】 陈宏平；

【作者基本信息】 太原理工大学 ， 市政工程， 2012， 硕士

【摘要】 随着钢铁产业的快速增长,作为该产业基础原料的焦炭的需求也有了很大提高,而炼焦所用水量是所得焦产量的2.5倍,可见焦化废水的排放量之大。焦化废水中氨氮的浓度很高,并且氨氮对水体、人类、工业等都会造成严重的威胁。然而,目前对焦化废水以及焦化废水中氨氮的处理效果均不理想,导致出水氨氮的含量无法达到排放标准。因此,对焦化废水中氨氮的去除已成为目前急需解决的问题之一。本文以焦化废水为处理对象,首先采用两级微氧EGSB反应器对其进行处理,通过实验得出两级微氧颗粒污泥对氨氮的去除效果较差,需要选用更适合的工艺对焦化废水中的氨氮进行去除。后期实验分别采用两级微氧颗粒污泥+硅藻土及微氧颗粒污泥+好氧污泥两种工艺对焦化废水中的氨氮进行去除。本课题主要研究内容及结果如下：1.采用两级微氧EGSB反应器处理进水COD含量为1120-2200mg/L的焦化废水时,在水力停留时间为12h,上升流速为2.7m/h,进水水温为28-35℃的条件下,系统对氨氮的去除效果较差。通过两级反应器之后的出水中氨氮浓度为40～157mg/L,不能满足排放要求,且氨氮总去除率最高仅为46%,甚至出现负的去除率。整个系统对氨氮的去除效果较差,出水中氨氮的浓度不能达到排放标准,需要采用更适合的工艺进行处理。2.采用两级微氧颗粒污泥+硅藻土工艺处理进水COD含量为1100-2060mg/L的焦化废水时,在水力停留时间为12h,上升流速为3.2m/h、2.9m/h,进水水温为25-29℃的条件下,可使出水氨氮浓度为2-12mg/L满足《污水综合排放标准》(GB8978-1996)的一级排放标准,当系统保证出水中氨氮浓度达标且稳定运行半个月后,停止向反应器内加入硅藻土处理效果仍然满足排放要求。系统运行稳定后,较长时间(1个月)的停止运行对反应器的再次运行及处理效果不会产生明显的不利影响。此外,进水氨氮浓度、硅藻土的投加量以及反应器内污泥浓度均会影响该工艺对氨氮的去除效果。3.采用微氧颗粒污泥+好氧污泥工艺处理进水COD含量为1600-2060mg/L的焦化废水时,在水力停留时间为12h,上升流速为3.2m/h,进水水温为23-29℃的条件下,可使出水氨氮浓度为0.2～10mg/L,满足排放标准。系统运行稳定后,较长时间(1个月)的停止运行对反应器的再次运行及处理效果不会产生明显的不利影响。此外,好氧系统的曝气时间及pH值均会影响该工艺对氨氮的去除效果。4.从技术方面研究,两级微氧颗粒污泥+硅藻土及微氧颗粒污泥+好氧污泥两种工艺,对氨氮的去除都具有高效、稳定的效果；从经济方面研究,微氧颗粒污泥+好氧污泥工艺运行投资费用远高于两级微氧颗粒污泥+硅藻土工艺。因此,两级微氧颗粒污泥+硅藻土工艺为焦化废水中氨氮的去除提供了一种新的高效、经济的方法。更多还原

【Abstract】 Along with the rapid growth of the steel industry, coke as the basic raw materials is increasingly demanded. However, the water consumption is2.5times in weight as the coke production. Therefore, the coking wastewater dischargement is tremendous. The concentration of ammonia nitrogen in the coking wastewater is very high and it is harmful to water body, human, industry and so on. However, the treatment on coking wastewater especially ammonia nitrogen in the coking wastewater is not satisfying at present which leading to the ammonia nitrogen concentration in effluent cannot meet discharge standards. Hence, the removal of ammonia nitrogen in coking wastewater has become one of the urgent problems at present. This experiment uses two-stage micro oxygen EGSB reactor to treat coking wastewater. It is proved that removal of ammonia nitrogen with this method is not well enough and a more suitable process is needed to remove the ammonia nitrogen in coking wastewater. Then the subsequent experiments adopt two-stage micro oxygen granular sludge+diatomite and micro oxygen granular sludge+aerobic sludge methods separately.The main contents and results of this research are as follows:1. In the two-stage micro oxygen EGSB reactors, with1120~2200mg/L of influent COD concentration, at12h of hydraulic retention time,2.7m/h of rising velocity and feeding water temperature of28～35℃, the ammonia nitrogen removal effect is low.The ammonia nitrogen concentration of the effluent after two-stage reactors is40to157mg/L and can’t meet discharge requirements. The highest total removal rate is only46%and sometimes it even has negative removal rate. The ammonia nitrogen removal effect in this system is low and the ammonia concentration in the effluent can’t meet the discharge standards. A more suitable process is needed.2. After the two-stage micro oxygen granular sludge+diatomite process, with1100-2060mg/L of influent COD concentration,12h of hydraulic retention time,3.2m/h to2.9m/h of rising velocity, feeding water temperature of2529℃, the ammonia nitrogen concentration of the effluent is2～12mg/L which meet the first level of discharging standard in the "integrated wastewater discharge standard"(GB8978-1996).When the system may make sure that the ammonia nitrogen concentration in effluent could meet the standard and operated steadily for half month, the adding of diatomite is ceased and it still meet meet the standard. After the system run stably for a period of time, a long time (1month) stopping won’t impact the restart and the treating effect obviously. In addition, the ammonia nitrogen concentration of influent, the diatomite dosage and the sludge concentration in the reactor all will affect the process on ammonia nitrogen removal effect.3. In the micro oxygen granular sludge+aerobic sludge system, with1600～2060mg/L of influent COD concentration, at12h of hydraulic retention time,3.2m/h of rising velocity and the feeding water temperature of23～29℃, the ammonia nitrogen concentration of the effluent is0.2～10mg/L which meets the discharge standard. After the system run stably for a period of time, a long time (1month) stopping won’t impact the restart and and the treating effect obviously. In addition, aeration time and pH value in the aerobic system will affect the process on ammonia nitrogen removal effect.4. From the point of technology, the two processes of two-stage micro oxygen granular sludge+diatomite and micro oxygen granular sludge+aerobic sludge both have efficient and stable removal effect on ammonia nitrogen; From the point of economy, the micro oxygen granular sludge+aerobic sludge process costs far higher in operation than two-stage micro oxygen granular sludge+diatomite process. Therefore, two-stage micro oxygen granular sludge+diatomite process has provided a new efficient and economic method for removing ammonia nitrogen in coking wastewater.更多还原