摘要
采用MRF模型和DPM模型对某污水厂新型旋流沉砂池(1×104m3/d)的除砂效率影响因素进行数值模拟,考察进水流量、搅拌桨高度及转速与砂粒去除率之间的关系,并将模拟结果与实测结果进行对比验证。结果表明:①砂粒去除率与进水流量成反比;当进水流量一定时,砂粒去除率与转速呈抛物状曲线关系;进水流量越大,最佳转速也越大,但对应的砂粒去除率则越小,且转速对砂粒去除率的影响亦越显著。②当转速为15 r/min时,砂粒去除率与搅拌桨高度呈现两种抛物状曲线关系;在不同进水流量下,搅拌桨最佳高度为150 mm左右。③当进水流量为400m3/h时,不同搅拌桨高度下砂粒去除率与转速呈抛物状曲线关系,搅拌桨高度与最佳转速呈现两种抛物状曲线关系;最佳搅拌桨高度应设在140～150 mm之间,最佳转速在15～25 r/min之间,对砂粒的最高去除率在60%～65%之间。
Abstract： The numerical simulation of factors influencing the grit removal efficiency of new rota- tional flow grit chamber （ 1 ×10^4m3/d） in a WWTP was conducted using MRF model and DPM model. The relationship of influent flow, impeller height and speed to grit removal efficiency was investigated, and the simulation data were compared and verified with the measured data. The results showed that （1） the grit removal efficiency was inversely proportional to the influent flow; the grit removal efficiency ver- sus impeller speed showed a parabolic-shaped curve at a given influent flow; the larger the influent flow, the larger the optimal impeller speed, but the lower the corresponding grit removal efficiency, and the more significant the influence of impeller speed on grit removal efficiency; （2） the grit removal efficiency versus impeller height showed two types of parabolic-shaped curves at an impeller speed of 15 r/min; and the optimal impeller height was about 150 mm at different influent flow rates; （3） at an influent flow rate of 400 ma/h, the grit removal efficiency versus impeller speed showed a parabolic-shaped curve at differ-ent impeller heights; the impeller height versus the optimal impeller speed showed two types of parabolic- shaped curves. The optimal impeller height should be set between 140 and 150 ram, the impeller speed should be set between 15 and 25 r/min, and the highest grit removal efficiency was 60% to 65%.
出处
《中国给水排水》
CAS
CSCD
北大核心
2013年第9期92-95,共4页
China Water & Wastewater
基金
国家高技术研究发展计划(863)项目(2009AA063801)
关键词
新型旋流沉砂池
除砂率
进水流量
搅拌桨转速
搅拌桨高度
二次环流
new rotational flow grit chamber
grit removal rate
influent flow
impellerspeed
impeller height
secondary circulation
