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自由沉淀平流式沉淀池设计参数的求解 总被引:1,自引:0,他引:1
自由沉淀平流式沉淀池设计参数的求解南国英(河北建筑工程学院)自由沉淀平流式沉淀池设计时,设计参数的合理选用是设计成败的关键。本文以拟和法[1]计算理论为基础,把推流型反应器的计算模式应用于自由沉淀平流式沉淀池的设计计算,以求得主导设计参数T(u0=H... 相似文献
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周仕铮 《土木建筑与环境工程》1988,10(4)
本文简述国内外关于沉淀模拟的基本理论,并探讨了周边进水式沉淀池处理城市污水的沉淀模拟方法。研究得出:城市污水中所含的凝聚性悬浮质点,在沉淀中的凝聚沉淀过程是以梯度凝聚为主,对于梯度凝聚沉淀过程的模拟,除按等速流原则违模和水质条件相似外,还必须使流入沉淀池的进水SS浓度和沉淀池尺寸的平方根成反比,即要实现公武C_o模/C_o原=(l_o原/l_o模)~(1/2)根据这一指导思想,进行了实验性质的模型对比试验和现场测定,通过对模型中水流流态的观察、对比测定模型与假想原型的水力特性参数和沉淀效率,验证了以上公式有足够的正确性和实用价值。 相似文献
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沉淀池构型不同其内部的流体流动特性差别很大、沉淀效率也存在很大差别。目前一般认为周边进水周边出水式的沉淀池较中心进水周边出水式的具有优势.然而周边进水周边出水式的沉淀池使用过程中也存在一些问题。如进、出水不均,絮状污泥上浮等.有待于进一步深入的研究加以改进。本文采用示踪实验技术分析了1,4圆周的周边进水周边出水式沉淀池内水流的流态。结果表明:(a)水流流动多环绕池壁,不能遍布整个沉淀池,降低了沉淀池的容积利用率;(b)在池中心区域的水长期滞留于池中,不易参与交换,从而造成处理效率降低;(c)实验是以自来水为原水进行的,实际情形混合液浓度为3000—4000mg/L,势必会减少流体绕边壁流动的动量。因而实际情形的流场有待于进一步的测量。 相似文献
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1 概述 在水处理过程中常利用沉淀池固液分离,尽管沉淀池型式各种各样,而去除水中悬浮颗粒的基本原理相同。在沉淀池设计时,常常采用经验方法,如选用较长的沉淀时间或较低的表面负荷率等。显然,这些设计方法有可能使沉淀池相差很大。 相似文献
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水平管沉淀分离装置的开发研究 总被引:1,自引:1,他引:0
水平管沉淀分离装置是将沉淀管水平放置,使水平行流动,悬浮物垂直沉淀,具有沉淀和分离两种功能.沉淀管水平放置,增大了沉淀面积,缩短了悬浮物的沉降时间,将沉淀管中沉淀下来的悬浮物与水及时分离,水走水道、泥走泥道,解决了悬浮物在沉淀过程中的可逆沉淀问题.杜绝了跑矾及泥堵塞沉淀管等现象的发生,提高了沉淀效率,降低了出水浊度,减轻了滤池负荷.沉淀管区也不需设置下部进水区和上部出水区,降低了沉淀池的深度,节省了基建投资,减少了占地面积.该装置设计新颖,构造巧妙,在沉淀池中可采取并联或串联的形式组装. 相似文献
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基于理想沉淀池相关理论,分析了平流式沉淀池的工作情况,研究了提高其处理能力和处理效率的方法,提出了沿途集水可以提高沉淀池的水力负荷,但一定程度地降低了处理效率,表明了通过中途集水实现沉淀池挖潜是可行的。 相似文献
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国内外给排水工程中,各种刮泥机已普通应用在圆型沉淀池上,取代了自然沉淀斗式排泥。在实际使用中刮泥机各有利弊,用于黄河高含砂量水处理中φ16m以下的,以行车式较可靠,但存在造价高、耗电高,中心进水和辐射出水不便之缺点。中国市政工程西北设计院给排水机电设备厂、兰州维尼纶厂水气分厂,联合攻 相似文献
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分析某污水二沉池上浮的主要原因,经过结构性能鉴定,在继续保留二沉池的原则下,实施了有效的复位纠偏方案,并实施基底压密注浆、池体结构细部处理等技术方案,使池体恢复了原结构受力状态和使用功能。 相似文献
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沉淀池表面负荷率与截留沉速应用讨论 总被引:1,自引:0,他引:1
杨镭 《华南建设学院西院学报》1994,(1)
本文阐述了沉淀池表面负荷率与截留沉速的概念,认为平流沉淀池与斜管沉淀池截留沉速不相同。分析目前我国平流沉淀池具有挖潜增产的能力。导出斜管沉淀池的表面负荷率与截留沉速之间的计算式,提出斜管沉淀池的截留沉速为0.13~(mm)/s~0.23~(mm)/s。 相似文献
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文章讨论了斜管沉淀池斜管固定悬索的设计问题。文中分析对比了单根索的近似解析法以及几何非线性有限元解法的结果,并用几何非线性有限元法验算了实际工程遇到的一些常见工况,最后针对设计工作提出了工程建议。 相似文献
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针对在活性污泥法工艺中究竟应该取消还是保留初沉池这一争论.通过静态和动态沉淀模拟试验,研究初沉池的水力停留时间与初沉池沉降效应的关系,以确定比较合适的初沉池水力停留时间.研究表明,初沉池沉淀时间控制在0.5~1.0h之内应该是适当的,一方面可维持初沉池的本来功能,同时也缓解脱氮除磷中存在的碳源矛盾;另一方面可降低工程基建投资. 相似文献
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在水厂沉淀池前部沿池宽方向增设侧向流不锈钢波纹斜板组,可在占地受限的情况下,有效改善现有水厂絮凝沉淀池的沉淀条件,达到进一步提高水质的目的. 相似文献
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Effects of orbital shaking on settling velocity of mineral particles in aqueous solutions using split‐plot designs
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Marzieh Hosseini‐Nasab 《Water and Environment Journal》2017,31(4):470-477
This study aimed to experimentally investigate and statistically test changes in the settling velocity of particles falling in an aqueous solution due to an orbital shaking of the container. A series of settling experiments were conducted on coal samples under different combinations of shaking speed and initial concentration of the particles. First, a generalized version of the factorial design (a split‐plot design) was utilized to obtain the acquired data. Then, an appropriate statistical model was fitted to experimental data using settling velocity as a response while shaking speed and initial coal concentration were defined as factors. Graphic patterns confirmed our hypotheses that settling velocity is affected by the shaking speed, initial coal concentration and the interaction of these two factors. Results of the analysis indicated that the main effects of both initial coal concentration (F‐statistic = 775.75) and shaking speed (F‐statistic = 11.96) on the settling velocity are strongly significant (both with a P‐value near zero). Moreover, a strong interaction of the effects of these factors on the response variable was also observed (F‐statistic is 10.57 with a P‐value of near zero). Based on the results, combination of 4% coal concentration and 50 rpm shaking speed resulted in the highest settling velocity of 1.21 cm/s. In contract, a combination of 10% coal concentration and 100 rpm shaking speed led to a settling velocity of only 0.55 cm/s. Findings of this study may have invaluable benefits to the mineral and water treatment industries where design and construction of thickeners and sedimentation tanks equipped with orbital shakers can significantly accelerate the sedimentation of mineral particles as well as water contaminants. 相似文献
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Towards a hydrodynamically enhanced design and operation of primary settling tanks – Results of a long term in situ measurement investigation program
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In modern wastewater treatment the function of primary settling tanks (PSTs) has become more complex comprising the control of readily biodegradable carbon between denitrification and biogas production by an optimum performance. This requires detailed investigations in order to obtain exact knowledge of the processes within PSTs. The article shows the results of the investigation of a PST comprising in situ flow measurements and removal efficiency analysis. The measurements were carried out at different surface overflow rates, which ranged from low to even higher values than those recommended by design guidelines. This was done in order to investigate the relationship between hydrodynamic processes and removal efficiency at high hydraulic loads. Inflowing and outflowing suspended solids concentrations and loads were recorded on‐line during the measurements. The measurements provided detailed insight into the flow processes within the PST as a first step towards hydrodynamically driven design and operation control of PSTs. 相似文献
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由于设计规范中对黄河高浊度水的沉淀池排泥管道阻力计算未作出规定,故有必要在分析黄河高浊度水沉淀池排泥浆体特点的基础上进行试验。结果表明,杜兰德公式不适用于沉淀池排泥浆体的计算,分别给出了未经预处理及经过预处理的黄河高浊度水沉淀浆体管道阻力计算公式,并计算出工程设计中常用钢管管径的管道阻力。 相似文献