The vortex concentrator for suspended solids treatment

The use of vortex concentrators is becoming increasingly popular for suspended solids reduction in combined sewer overflows and stormwater. This study is a laboratory investigation of the use of vortex concentrators to reduce the solids concentration of synthesized stormwater. The synthesized stormwater was made with water and addition of particles; sand, granular activated carbon, and sewer sediments. The vortex concentrator was made of acryl resin 300 mm in diameter. To determine the efficiency for various influent suspended solids (SS) concentrations, tests were performed with different SS concentrations. The samples were taken simultaneously at the influent storage tank and effluent tank, and measured SS concentrations. The range of surface loading rates were 120 to 850 m3/m2/day, and influent SS concentrations were varied from 300 to 5,000 mg/L. To determine the optimum coagulant dosage, jar tests were conducted with coagulants such as PAM and PAC. It was found that optimum coagulant and its dosage were PAM and 2 mg/L. The overall SS removal efficiency of the vortex concentrator for typical stormwater was estimated at about 65%. With an increase of SS concentration, the removal efficiency was increased. Since the SS concentration of stormwater was higher than 1,000 mg/L, the removal efficiency of the vortex concentrator for stormwater could be estimated to be 65-70%. The SS removal efficiency was increased with an increase of retention time, and the optimum retention time was 0.15-1.0 minutes. With an increase of the foul to overflow QF/Qo, a key parameter for vortex concentrator operation, the removal efficiency was increased. An alternative solution to improve treatment efficiency might be to set a follow-up retention basin. Based on a series of settling tests on the treated overflow water from the vortex concentrator, 5 to 10 minutes hydraulic retention time in a follow-up retention basin would substantially improve the results.

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Program on Treatment of the Landfill Leachate by Onland Planting Reed (Phragmites)

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.2852 ◽

2011 ◽

Vol 71-78 ◽

pp. 2852-2855

Author(s):

Kun Shi ◽

Ming Zou

Keyword(s):

Removal Efficiency ◽

Constructed Wetland ◽

Landfill Leachate ◽

Retention Time ◽

Suspended Solids ◽

Preferential Flow ◽

Hydraulic Retention Time ◽

Oxygen Demand ◽

Surface Loading ◽

Waste Landfill

The microcosm tests were done to estimated the HRT (Hydraulic Retention Time) and removal efficiency of reflowing treatment of the landfill leachate collected from Dalian Maoyingzi Municipal Solid Waste Landfill, which contained high levels of COD (Chemical Oxygen Demand, 38400 mg/L) and SS (Suspended Solids, 650 mg/L) by the reed constructed wetland located in the south area of Dalian Jiaotong University. The results showed that: (1) The HRT in nature soil cuboids were significant shorter than those in sieved soil cuboids (P<0.01); (2) The removal efficiency among the output water with the trend as follows: Preferential flow (53.9%)<Percolating water (59.2%)<Reflowing water (63.3%); (3) The COD and SS were decreased from 38400 and 650 mg/L to 14080 and 213 mg/L by the way of reflowing with the HSL (Hydraulic Surface Loading) of 0.16 m3/(m2·d) by reflowing (Removal efficiency: COD: 63.3%; SS: 67.3%).

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UJI PERFORMANCE BIOFILTER ANAEROBIK UNGGUN TETAP MENGGUNAKAN MEDIA BIOFILTER SARANG TAWON UNTUK PENGOLAHAN AIR LIMBAH RUMAH POTONG AYAM

Jurnal Air Indonesia ◽

10.29122/jai.v1i3.2357 ◽

2018 ◽

Vol 1 (3) ◽

Cited By ~ 1

Author(s):

Nusa Idaman Said ◽

Firly Firly

Keyword(s):

Removal Efficiency ◽

Retention Time ◽

Suspended Solids ◽

Total Suspended Solids ◽

Pilot Scale ◽

Continuous Operation ◽

Main Research ◽

Aerobic Process ◽

Plan Study ◽

Plastic Media

An experiment of anaerobic biofilter using honeycomb plastic media was conducted in semi-pilot scale. This paper describes the pilot plan study of chicken’s slaughterhouse wastewater treatment using anaerobic and aerobic submerged biofilter using honeycomb plastic media. The main research was conducting by continuous operation under condition 4 days, 2 days and 1 day retention time. The result of experiment shows that within the anaerobic process under conditions 1- 4 days retention time, the removal efficiency of COD were 78 – 87 %, BOD were 78 – 89 %, 73 – 83 % , and Total Suspended Solids (TSS) were 83 – 96 % respectively. Using combined anaerobic and aerobic process under same conditions 1 - 4 days retention time shows increasing of removal efficiency. The removal efficiency of COD were 86 – 90 %, BOD were 85 – 90 %, Organics (KMnO4) were 81 – 88 % and Total Suspended Solids (TSS) were 94 – 96 % respectively. The longer retention time has resulted in higher removal efficiency. Kata Kunci : Biofilter anaerobik, media sarang tawon, air limbah, rumah potong ayam.

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Experimental abatement data of underflow baffles for removal of floatables in the CSOs of the Greater Montréal (Canada) area

Water Science & Technology ◽

10.2166/wst.2005.0033 ◽

2005 ◽

Vol 51 (2) ◽

pp. 65-70 ◽

Cited By ~ 2

Author(s):

John F. Cigana ◽

Martin Couture

Keyword(s):

Pilot Scale ◽

Horizontal Velocity ◽

Design Criteria ◽

Operational Cost ◽

Flow Conditions ◽

Combined Sewer Overflows ◽

Follow Up Study ◽

Combined Sewer ◽

Rapid Flow

Underflow baffles have gained in popularity over the years as a viable mean to intercept floatables in Combined Sewer Overflows (CSOs). This choice was mainly justified by the extremely low capital cost (CAPEX) and operational cost (OPEX) of this solution, although the efficiency of underflow baffles has never been clearly proven. The only similar application to underflow baffles are scum boards in grit chambers and clarifier. However, the flow conditions at CSOs vary considerably from those in grit chambers and clarifier. For this reason, review of the behavior of floatables in a rapid flow is paramount. Only then can comprehensive design criteria for underflow baffles and overflow chambers be suggested. Pilot scale tests, performed in a 17 metres long basin at various flowrates, had already shown that a critical horizontal velocity for floatables (Vcr) may develop in the overflow chambers. In this follow up study, the fate of intercepted floatables was investigated. It appears from this latest data that permanent capture of floatables decreases rapidly with an increase in the horizontal velocity of the flow, no matter what the baffle depth. Baffle depth increases capture at lower velocities (0.17 m/s) but become irrelevant at higher velocities (0.61 m/s). This data suggests that capture efficiency of existing underflow baffles in overflow chambers can be, at best, very low whenever the horizontal velocity increases above 0.30 m/s or 1 ft/s.

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The potential of ultrasonic membrane anaerobic systems in treating slaughterhouse wastewater

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2015.107 ◽

2015 ◽

Vol 5 (3) ◽

pp. 293-300 ◽

Cited By ~ 3

Author(s):

N. H. Abdurahman ◽

Y. M. Rosli ◽

N. H. Azhari ◽

Hayder A. Bari

Keyword(s):

Steady State ◽

Removal Efficiency ◽

Retention Time ◽

Suspended Solids ◽

Oxygen Demand ◽

Yield Coefficient ◽

Slaughterhouse Wastewater ◽

Mixed Liquor ◽

Solids Retention Time ◽

Solids Retention

Direct discharge of slaughterhouse wastewater causes serious environmental pollution due to its high chemical oxygen demand (COD), total suspended solids (TSS) and biochemical oxygen demand. In this study, an ultrasonic-assisted membrane anaerobic system was used as a novel method for treating slaughterhouse wastewater. Six steady states were achieved, using concentrations of 7,800–13,620 mg/l for mixed liquor suspended solids and 5,359–11,424 mg/l for mixed liquor volatile suspended solids (MLVSS). Kinetic equations were used to describe the kinetics of treatment at organic loading rates of 3–11 kg COD/m3/d. The removal efficiency of COD was 94.8–96.5% with hydraulic retention times of 308.6–8.7 days. The growth yield coefficient was found to be 0.52 g VSS/g. COD was 0.21 d−1 and methane gas production rate was 0.24–0.56 l/g COD/d. Steady-state influent COD concentrations increased from 8,000 mg/l in the first steady state to 25,400 mg/l in the sixth steady state. The minimum solids retention time, θcmin obtained from the three kinetic models was 6–14.4 days. The k values were 0.35–0.519 g COD/g VSS.d and μmax values were between 0.26 and 0.379 d−1. The solids retention time decreased from 600 to 14.3 days. The complete treatment reduced the COD content and its removal efficiency reached 94.8%.

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Constructed wetlands for combined sewer overflow treatment in a Mediterranean country, Portugal

Water Science & Technology ◽

10.2166/wst.2013.180 ◽

2013 ◽

Vol 67 (12) ◽

pp. 2739-2745 ◽

Cited By ~ 6

Author(s):

R. Amaral ◽

F. Ferreira ◽

A. Galvão ◽

J. S. Matos

Keyword(s):

Constructed Wetlands ◽

Retention Time ◽

Suspended Solids ◽

Oxygen Demand ◽

Total Suspended Solids ◽

Mediterranean Country ◽

Combined Sewer Overflow ◽

Combined Sewer ◽

Removal Efficiencies ◽

Sewer Overflow

The use of constructed wetlands as a valuable and attractive method for combined sewer overflow (CSO) treatment has been demonstrated in several studies. In Portugal, a Mediterranean country having usually a long dry period, there are still no applications of this technology. The purpose of this research is to gather information and know-how required for the design and management of this type of infrastructure. A pilot-scale experimental setup for CSO treatment was installed and evaluated in situ, in terms of organic matter, total suspended solids and microorganism removal with emphasis on the results of the start-up. After 1 day of retention average removal efficiencies of 73–79% and 82–89% were obtained in terms of chemical oxygen demand (COD) and total suspended solids (TSS), respectively. During the remaining retention time a slower removal was observed. After 7 days, the COD removal efficiencies reached 86–91% and the TSS removal efficiencies reached 93–97%. On average, after 1 day, reductions of 1.2–2.0 log and 1.9–2.4 log, respectively, for total coliforms and Enterococcus were observed. For a retention time of 7 days these reductions attained 4.0–4.9 log and 4.4–5.3 log, respectively.

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An Evaluation of Solid Removal Efficiency in Coagulation System for Treating Combined Sewer Overflows by Return Sludge

Journal of Korean Society of Environmental Engineers ◽

10.4491/ksee.2013.35.3.171 ◽

2013 ◽

Vol 35 (3) ◽

pp. 171-178 ◽

Cited By ~ 1

Author(s):

Sung-Ryong Ha ◽

Seung-Chul Lee

Keyword(s):

Removal Efficiency ◽

Coagulation System ◽

Combined Sewer Overflows ◽

Combined Sewer ◽

Sewer Overflows

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Modified vortex separator and UV disinfection for combined sewer overflow treatment

Water Science & Technology ◽

10.2166/wst.1995.0535 ◽

1995 ◽

Vol 31 (3-4) ◽

pp. 263-274

Author(s):

M. C. Boner ◽

D. R. Ghosh ◽

S. R. Harper ◽

B. G. Turner

Keyword(s):

Environmental Protection Agency ◽

Uv Light ◽

Water Environment ◽

Field Tests ◽

Uv Disinfection ◽

Combined Sewer Overflows ◽

Solids Concentration ◽

Combined Sewer ◽

Vortex Separator ◽

Dissolved Air

This paper presents the results of a study to evaluate the efficiency of a modified vortex separator (MVS) and an ultraviolet (UV) disinfection unit for direct treatment of combined sewer overflows (CSOs). The MVS included dissolved air and coagulant addition. The effluent from the vortex separator was disinfected continuously using UV light. Bench-scale tests were performed on CSO samples to screen various coagulants and operating pressures for dissolved air. Field tests were performed at the CSO pilot facility where simulated as well as actual storm-generated overflow events were studied. Performance comparisons between the MVS and other CSO treatment technologies are presented. Results indicate that the MVS achieves pollutant removals superior to conventional sedimentation for the same surface loading rates, or can be hydraulically loaded several times higher than sedimentation to achieve the same results. The results also indicate that the MVS significantly improved solids concentration capability when compared to the conventional operation of the vortex separator. UV disinfection performance was dependent on TSS removal and showed promise for full scale implementation when combined with MVS treatment. This project was sponsored by the Water Environment Research Foundation and was a collaborative effort between ten participating organizations including the US Environmental Protection Agency (EPA), municipalities, consulting firms and equipment manufacturers.

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Modelling total suspended solids, E. coli and carbamazepine, a tracer of wastewater contamination from combined sewer overflows

Journal of Hydrology ◽

10.1016/j.jhydrol.2015.10.042 ◽

2015 ◽

Vol 531 ◽

pp. 830-839 ◽

Cited By ~ 16

Author(s):

Khemngeun Pongmala ◽

Laurène Autixier ◽

Anne-Sophie Madoux-Humery ◽

Musandji Fuamba ◽

Martine Galarneau ◽

...

Keyword(s):

Suspended Solids ◽

Total Suspended Solids ◽

Combined Sewer Overflows ◽

E Coli ◽

Combined Sewer ◽

Sewer Overflows

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A Water Elutriation Apparatus for Measuring Settling Velocity Distribution of Suspended Solids in Combined Sewer Overflows

Water Quality Research Journal ◽

10.2166/wqrj.2004.054 ◽

2004 ◽

Vol 39 (4) ◽

pp. 432-438 ◽

Cited By ~ 7

Author(s):

Bommanna G. Krishnappan ◽

Jiri Marsalek ◽

Kirsten Exall ◽

Robert P. Stephens ◽

Quintin Rochfort ◽

...

Keyword(s):

Velocity Distribution ◽

Suspended Solids ◽

Settling Velocity ◽

Settling Chamber ◽

Combined Sewer Overflows ◽

Polymer Addition ◽

Combined Sewer ◽

Sewer Overflows ◽

Settling Velocity Distribution ◽

Chemical Distribution

Abstract An elutriation apparatus has been proposed for determining the settling velocity distributions of suspended solids in combined sewer overflows (CSOs). The apparatus consisted of a series of interconnected cylindrical settling chambers, through which the sample was drawn using a peristaltic pump attached to the outlet of the last settling chamber. Since the diameters of the cylinders were progressively increasing, sediment with different settling velocities settled in different cylinders. By measuring the amount of sediment in each cylinder, the settling velocity distribution was deduced. The apparatus was tested using samples from a CSO outfall in Hamilton, Ontario, Canada. The test results showed that the apparatus performed well for determining settling characteristics of suspended solids and chemical distribution in different settling fractions. The effectiveness of polymer addition to enhance flocculation and settling of CSOs was also tested in this apparatus. The elutriation apparatus proposed here offers several advantages over the traditional methods (i.e., settling columns) of measurements of settling velocity distributions. The main advantage is its ability to measure the distributions under dynamic conditions, i.e., in the presence of flow. Consequently, the elutriation apparatus reproduces flow conditions in actual settling tanks better than conventional settling columns.

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