混凝浑液面沉速与混凝剂投加量的关系研究(1)
2017-06-28 01:04
导读:理工论文论文,混凝浑液面沉速与混凝剂投加量的关系研究(1)论文样本,在线游览或下载,科教论文网海量论文供你参考:
摘要:探讨了黄河高浊度水混凝沉淀浑液面沉迷与自然沉迷之间
摘要:探讨了黄河高浊度水混凝沉淀浑液面沉迷与自然沉迷之间的相关性,经过对实验数据进行线性回归提出了混凝过程中浑液面沉速与自然沉速、含沙量、pam投加量之间的经验公式。运用该经验公式得出的浑液面沉速计算值与实测相对误差在0.43%-12.27%之间。
关键词:黄河 给水处理 高浊度水 混凝 沉淀 a study of relationship between precipitating rate of cloudy liquid level
during coagulation and dose of coagulant
abstract:the relationship between the preeipitating rate of the high-turbidity water of the yellow river caused by coagulation and the natural precipitating rate of the water is discussed and an empirical formula of relationship between the precipitating rate of cloudy liquid level during coagulation and the natural precipitating rate, sand content as well as dosage of pam is proposed through linear regression of the experimental data. the relative errors between the calculated values of precipitation of the cloudy liquid level obtained by applying the said empirical formuia and the actually measured values ranged between 0.43%~12.27%.
key words: yellow river; feed water treatment; high-turbidity water; coagulation; precipitation 混凝沉淀是黄河高浊度水处理常用的方法。提高浑液面沉速,节约药剂(pam)的投加量达到多出清水是高浊度水处理的主要目标。然而混凝过程极其复杂,影响浑液面沉速的因素有高浊度水的性质、pam投加量、速度梯度c、搅拌时间t等。因为高浊度水自然沉淀沉速与原水的性质密切相关。在实际处理一定组成的高浊度水时,可以借助实验得到的经验关系,根据浑液面的自然沉速以及所希望达到的浑液面沉速来确定pam的投加量。本文先采用正交实验的方法确定混凝过程的混合、反应的最佳水力条件,然后在此基础上研究浑液面沉速与pam投加量及高浊度自然沉速之间的关系。1 实验方法1.1 自然沉降实验
(科教作文网 zw.nseac.com整理) 高浊度水采用郑州上街段黄河泥沙配制而成。试验过程中所有水样水温15±1℃。用nsy-1光电颗分仪测泥沙粒度,其当量直径dm由下式计算:
dm=1/(∑(△pi/di))
式中di——颗粒粒径,pi——粒径di颗粒占所有颗粒质量百分数。选出dm相近的几组水样用比重瓶测定其含沙量,以cw(kg/m3)表示。然后用直径62mm,高500mm,有效体积1500ml的自制沉降筒做静置沉降实验,根据沉降曲线求得等速沉降段混液面沉降速度作为自然沉速,以从(mm/s)表示。
试样的含沙量cw,浑液面自然沉速u0,当量直径dm,见表1:
表1 试样情况试样编号cw/(kg.m-3)dm/μmuo/(mm.s-1)
1 46.55.50.0157
2 79.59.50.0175
3 84.29.40.0161
4 101.59.40.0130
5 58.012.80.0385
6 75.612.80.0270
7 94.512.80.0210
8 115.312.80.0161
9 35.518.40.0990
10 67.518.40.0492
11 83.218.40.0381
12 94.718.40.0345
13 46.025.30.1100
14 55.025.30.0955
15 64.025.30.0790
16 79.525.30.0645
17 69.830.10.0860
18 125.530.10.0467
表2 各试样实测浑液面沉速与计算值对照试样编号uo/(mm.s-1)cw/(kg.m-3)d/(mg.l-1)u/(mm.s-1)u计算/(mm.s-1)相对误差/%