摘要
水处理工艺中受场地和低温低浊原水影响,加钒过程中会出现矾花形成不明显,沉淀效果不好的情况,此时就需要添加助凝剂,常规助凝剂为聚丙烯酰胺,但丙烯酰胺单体具有一定毒性,使用受限。通过对12种生物类胶体分别做强化混凝试验,并与聚丙烯酰胺对比,得出黄原胶在水温10~30℃,pH 6~9内作为助凝剂在混凝沉淀过程中效果显著。结果表明:通过混凝沉淀试验,聚合氯化铝浓度为6 mg/L,200 r/min快速搅拌1 min,加入黄原胶助凝剂浓度为0.09 mg/L时,60 r/min慢速搅拌5 min,静置5 min,测定浊度值,浊度降低率可从53.63%提高到72.74%。将实验室数据应用到水厂放大试验,当黄原胶助凝剂浓度为0.1 mg/L时,浑浊度降低率可从68.52%提高到81.91%。以10万m^(3)/d供水规模水厂测算,采用黄原胶做助凝剂生产成本较聚丙烯酰胺低,增加约0.003元/t,黄原胶作为助凝剂在水处理工艺中是可行的。
The formation of alum flower is not obvious and the precipitation effect is not good in the process of adding vanadium under the influence of the site and low temperature and low turbidity raw water in the water treatment process.At this time,it is necessary to add coagulant aids.Conventional coagulant aids is polyacrylamide,but acrylamide monomer has certain toxicity,which limits its use.12biological colloids were used for coagulating sedimentation compared with polyacrylamide.It can be concluded that xanthan gum has a significant effect in the process of coagulation and precipitation as a flocculant aid when water temperature was 10~30℃at pH 6~9.The results show that the turbidity reduction rate can be increased from 53.63%to 72.74%when the concentration of polyaluminum chloride was 6mg/L with a rapid mixture at 200r/min for 1min.Thenceforth,xanthan gum solution was added as flocculant aid at 0.09mg/L with a slow mixture at 60r/min for 5min,the turbidity was measured after standing 5min.Applying laboratory data to water plant scale-up experiments,the turbidity reduction rate can be increased from 68.52%to 81.91%when the concentration of xanthan gum was 0.1mg/L.Based on the calculation of a 100000m^(3)/d water supply scale water plant,the production cost of using xanthan gum as a coagulant aid is lower than that of polyacrylamide,increase by about 0.003yuan/t.Therefore xanthan gum is feasible in the water treatment process as a coagulant aid.
作者
严伟
程劲华
李燕琴
王云龙
郭后庆
董园
YAN Wei;CHENG Jinhua;LI Yanqin;WANG Yunlong;GUO Houqing;DONG Yuan(Jingmen Yongquan Water Quality Testing Co.,Ltd.,Jingmen 448000,China;School of life sciences,Tsinghua University,Beijing 100091,China)
出处
《给水排水》
CSCD
北大核心
2023年第S01期1-4,共4页
Water & Wastewater Engineering
基金
2021年度荆门市一般科技计划项目(2021YFYB132)
关键词
混凝沉淀
黄原胶
助凝剂
水处理
Coagulating sedimentation
Xanthan gum
Flocculant aid
Water Treatment
