文档介绍：摘要

近年来,随着膜技术的快速发展,反渗透(RO)工艺作为主要的污水再生
操作单元之一,在污水回用领域内占有了重要的地位。但伴随着 RO 浓水(ROC)
的剧增,其中的难生物降解有机物和高盐度成为水处理领域急需攻克的难题,浓
水若得不到妥善的处理而直接排放,必然会对土壤、地表水、海洋环境等产生不
利影响。本课题针对天津某石化厂废水回用车间的 RO 浓水,采用造粒软化法和
粉末活性炭(PAC)累积逆流吸附-微滤(MF)联用技术对其中的硬度和有机污
染物进行了去除研究。
造粒软化法较沉淀软化法具有提高药剂利用率、加速软化过程等优点。研究
利用 CaCO3 作为晶种,NaOH 为软化药剂去除 RO 浓水中的硬度。试验表明,投
加晶种可以提高硬度的去除率,且出水浊度较低。当造粒 30 次后可认为晶种制
备工作完成,试验在硬度去除率为 70%前提下的最佳软化条件为 NaOH 投量为
g/L、晶种投加量为 2 g/L、180 r/min 搅拌 30 min 后静置沉淀 30 min。
粉末活性炭吸附-微滤组合工艺能够有效地去除 RO 浓水中的有机污染物,
累积逆流吸附充分发挥了 PAC 的吸附容量。根据理论计算,在相同吸附效果下,
累积二级逆流吸附比单级吸附可节约 40%以上的 PAC,本研究通过动态反应器
试验验证了理论计算的正确性。RO 浓水经处理后,出水的 DOC 和 COD 均能够
接近出水目标值。该工艺在能够高效去除浓水中的有机污染物的同时节约炭的投
加量,增加了工艺的经济性,具有良好的发展前景。连续曝气,间歇排炭和增大
稀释因子可以有效地减轻微滤膜的膜堵塞与膜污染现象,减缓膜比通量的下降;
运行结束后将膜进行化学清洗,膜比通量可以基本恢复。

关键词:反渗透浓水;硬度;造粒;有机污染物;粉末活性炭;累积二级逆流
吸附;微滤
ABSTRACT

In recent years, with the rapid development of membrane technology, reverse
osmosis technology took an important place in the field of wastewater reuse as the
main wastewater regeneration unit operation. But along with the dramatic increase in
the quantity of reverse osmosis concentrate (ROC), the problems originated from
anic matter and high salinity in the ROC needed to be solved in the
water industry field. If the concentrate did not properly handled before emission, it
would inevitably have a negative influence on the soil, the surface water, the marine
environment and so on. Granulation softening method and powdered activated
carbon(PAC) adsorption-microfiltration(MF) combination process were used to
remove the hardness and anic pollutants in the ROC, witch came from a
petrochemical wastewater reuse workshop in Tianjin.
Granulation softening method could improve the utilization of chemicals,
accelerate the softening pared with precipitation softening method.
Calcium carbonateand sodium hydroxide were respectively used as seed crystal and
softening agent to remove the hardness of the ROC. The test showed that addition of