【作者】 靳俊伟；

【导师】 林衍；

【作者基本信息】 重庆大学 ， 环境工程， 2004， 硕士

【摘要】 粘胶纤维是一种开发最早的化学纤维,它以木材或棉短绒制成的浆粕为原料,产品的性质接近或超过天然的棉花纤维,在化纤中占有重要地位。粘胶纤维生产过程中需要大量的化工原料,如二硫化碳、硫酸、硫酸锌等,它们只参与工艺过程,并不构成产品的组分,其中的80%将转变成废物,污染大气和水体,对人类及环境产生很大的危害。目前,国内粘胶纤维生产废水普遍采用曝气脱硫—中和除锌的一级物化处理工艺,但处理后的污水达不到排放标准,Zn2+和CODcr超标。而常规的物化-生化治理工艺存在运行效果不够稳定、占地面积大和投资高等问题。本文针对宜宾丝丽雅粘胶纤维混合废水,采用CASS-物化工艺对其进行处理,探索了各种工艺操作条件对处理效率的影响,并对其影响机理进行了初步探讨。本文的主要研究内容有:1) 通过长期的连续实验,对CASS反应器处理粘胶纤维混合废水的启动、处理效果以及各种因素对处理效果的影响进行了研究。结果发现,污泥通过培养、驯化65天(此期间CASS周期为12小时)后,污泥负荷达到0.10～0.20 kgCODcr/ kgMLSS·d,CASS生化工艺的CODcr和BOD5的平均去除率达到77.12%和86.94%。这表明污泥已经适应粘胶纤维混合废水的处理环境。然后从第71天起进入正常运行期,在CASS周期为8小时时,CODcr和BOD5的平均去除率达到77.1%和89.16%。在周期调整为6个小时后,CODcr和BOD5的平均去除率达到75.44%和86.44%。试验表明,在0.30～0.36kgCODcr/ kgMLSS·d(0.08～0.13kg BOD5/ kgMLSS·d),CODcr的去处率一直稳定在75%～80%。在正常运行期,其进水BOD5的浓度变异系数为25.5%的情况下,相应的BOD5去处率的变异系数为5.6%。证明CASS系统具有良好的抗冲击负荷能力。2)通过实验室小试筛选出适合粘胶纤维混合废水的混凝剂和助凝剂。小试表明在投加约470～900mg/L的PAC和约2mg/L的PAM后,出水的CODcr能达到GB8978-1996《污水综合排放标准》一级排放标准即CODcr100mg/L。然后在CASS生化处理达到正常运行后,根据小试结果投加混凝剂和助凝剂。从中试结果可以看出,生化出水经过物化絮凝后,出水的CODcr平均去除率达到85%,BOD5平均去除率达到79%。出水的CODcr、BOD5及色度等指标均达到了排放标准。本研究为工程设计及运行提供了初步的理论依据及工艺条件。在工程中可根据实际情况进一步调整,使处理效果达到最佳。更多还原

【Abstract】 The viscose fiber which taken cotton and wood pulp as raw material plays animportant role in chemical cellulose. While during its production, wastewater with high concentration is produced due to consuming a lot of chemical raw material and it will cause environment hazards if it is not properly treated. Nowadays the wastewater can’t accord with the discharging standard by the current treated process. A study was carried out to assess the efficiencies of Cyclic Activated Sludge System (CASS) to treat wastewater of viscose fiber and find out proper coagulant. The main object was to assess the effect on a pilot scale reactor, while studying the behavior of the system at different operation condition and search a suited coagulant that can effetely treat the wastewater. The results show, after 65 days, the CODcr and BOD5 removal efficiency can be respectively improved to 77.12% and 86.94% when the activated sludge loading is 0.05 kgCODcr/ kgMLSS·d. And this proves the activated sludge has been adapted to the wastewater of viscose fiber. From the 71th day, it enters the normal operation period and the operational cycle time is adjusted to eight hours from original twelve hours, then from the 91th day, the operational cycle time is adjusted to six hours from original eight hours. The pilot shows CODcr removal efficiency is stabilized within 75%~80% that proves the CASS system has sound capability to resist shock load. The laboratory experiment shows the CODcr of effluent water can accord with one level of discharging standard by adding PAC(470～900mg/L) and PAM (2mg/L). From the pilot experiment, we can get a conclusion that the CODcr and BOD5 removal efficiency can be respectively improved to 85% and 79%. And all the targets of effluent water meet the design requirement. Through this experiment research, the operational parameters and technology foundations can be offered for project design and running. In the real project, the factors should be modified according to the reality to get the best results.更多还原