【作者】 刘彤；

【导师】 崔崇威；

【作者基本信息】 哈尔滨工业大学 ， 环境工程（专业学位）， 2018， 硕士

【摘要】 净水厂在生产饮用水的过程中会产生很多废水,约占净水厂生产水量的2%-10%。随着社会的不断发展以及饮用水的需求量不断增加,净水厂的规模和数量在不断增加,因此导致产生的生产废水的量也不断增加。排泥水中含有的大量的胶体颗粒、悬浮物、混凝剂以及混凝剂产生的氢氧化物等物质。将净水厂产生的排泥水直接排入到水体后,会对环境造成一定程度的污染,对排泥水的处理不仅对环境有所保护,还可以节约水资源。本研究对我国北方某净水厂的沉淀池排泥水进行处理研究。通过对该净水厂的进水原水来源和水质,以及沉淀池排泥水的水质进行分析。利用生产废水水量和污泥量的计算公式,从而确定排泥水的量和产泥量。对沉淀池排泥水自然沉降性能进行分析,当排泥水浓度较高时,沉淀性能较差。采用混凝沉淀的方法,利用多种混凝剂对沉淀池排泥水进行混凝处理,选取最佳的混凝剂为PAM、最佳投加量为10mg/L,PAM在混凝20分钟后沉淀污泥浓缩率不会有较大变化。排泥水浓度越低,PAM在相同时间混凝的沉淀污泥含水率越低。通过对排泥水的离心处理,当离心转速为4000rmp、离心时间15分钟时时间最佳。当排泥水浓度越高,离心分离的污泥的含水率越高。重力沉降的上清液水质稍差,少部分的检测项目指标高于国家《生活饮用水卫生标准》(GB5749-2006)标准,上清液可与净水厂进水一起混合处理。将自然沉降后的排泥水利用陶瓷膜进行处理,在曝气条件下可以减缓膜堵塞,通过比较,选取合适开始膜通量持续运行。分析不同的运行的状况对陶瓷膜的堵塞的情况,确定合适的膜清洗条件。利用各个最佳条件因素,陶瓷膜处理采用间歇反冲洗法,可将自然沉淀后的排泥水浓缩5倍左右。将陶瓷膜处理后的排泥水再通过离心作用进行处理,浓缩污泥的含固率接近4%。离心分离水出水水质稍差,可与净水厂进水一起混合处理。陶瓷膜出水符合国家《生活饮用水卫生标准》(GB5749-2006)标准,可将出水通入滤池一起处理。通过对混凝沉降、陶瓷膜处理、重力沉降三种方法对排泥水预处理进行经济分析,结果表明重力沉降对排泥水预处理费用最低。将预处理的排泥水利用陶瓷膜处理方法浓缩,然后利用离心处理的方式进一步泥水分离,处理的经济费用为1.70元/吨。更多还原

【Abstract】 Water purification plants produce a lot of wastewater during the production of drinking water,accounting for about 2% to 10% of the water produced by the water purification plant.With the continuous development of society and the increasing demand for drinking water,the scale and number of water purification plants are constantly increasing.As a result,the amount of production waste water generated also increases.The sludge contains a large amount of colloidal particles,suspended solids,coagulants,and hydroxides produced by the coagulant.After the sludge discharged from the water purification plant is directly discharged into the water body,it will cause a certain degree of pollution to the environment.The treatment of the discharged mud water not only protects the environment but also saves water resources.This study investigated the treatment of sedimentation sludge from a sedimentation tank in a purification plant in northern China.The raw water source and quality of the influent water in the water purification plant,as well as the quality of the sludge discharged from the sedimentation tank were analyzed.Using the formula for calculating the amount of waste water and sludge in the production process,the amount of sludge discharged and the amount of sludge produced can be determined.The sedimentation performance of sedimentation ponds was analyzed.When the sludge concentration was high,the sedimentation performance was poor.Using the method of coagulation and sedimentation,use a variety of coagulants to coagulat e sludge in sedimentation tanks,select the best coagulant for PAM,the optimal dosage is 10mg/L,PAM after coagulation for 20 minutes Precipitated sludge concentration rate will not change significantly.The lower the sludge concentration,the lower the m oisture content of the precipitated sludge that is coagulated by PAM at the same time.By centrifuging the sludge,the time is best when the centrifugal speed is 4000 rpm and the centrifugation time is 15 minutes.The higher the sludge concentration,the h igher the moisture content of the centrifuged sludge.The gravity sedimentation supernatant water quality is slightly poorer,and a small part of the test items are higher than the National Standard for Drinking Water Sanitary Standards(GB5749-2006).The supernatant can be mixed with the water purification plant influent water.The natural sedimentation sludge is treated with a ceramic membrane,which can slow down the membrane blockage under aeration conditions.By comparison,the appropriate starting membrane fluxes are continuously operated.Analyze the condition of clogging of the ceramic membrane with different operating conditions and determine the appropriate membrane cleaning conditions.Using various optimum conditions,the ceramic membrane was treated with an intermittent backwashing process to concentrate the natural precipitated mud water approximately 5 times.The sludge treated by the ceramic membrane was treated by centrifugation.The solid content of the concentrated sludge was close to 4%.T he water quality of the centrifugal separation water is slightly poor,and it can be mixed and treated together with the water purification plant.The effluent of the ceramic membrane meets the National Standard for Drinking Water Hygiene(GB5749-2006),and the effluent can be treated together with the filter.The economic analysis of the sludge pretreatment by three methods of coagulation settlement,ceramic membrane treatment,and gravity settlement shows that gravity sedimentation has the lowest pretreatment cost for sludge removal.The pretreated sludge was concentrated by a ceramic membrane treatment method and then further separated by centrifugation.The economic cost of treatment was 1.70 yuan/ton.更多还原