Treatment of road runoff by coagulation/flocculation and sedimentation

2019 ◽  
Vol 79 (3) ◽  
pp. 518-525 ◽  
Author(s):  
F. Nyström ◽  
K. Nordqvist ◽  
I. Herrmann ◽  
A. Hedström ◽  
M. Viklander

Abstract A laboratory investigation of the treatment potential of a coagulation process in the context of stormwater treatment was undertaken. The initial 25 L road runoff generated from four rain events was collected and subjected to a jar-testing regime with two commercial coagulants. The treatment effect was assessed by analysing the runoff before and after treatment for turbidity, suspended solids and metal content. The coagulation process resulted in particle and total metal reduction of more than 90% compared to 40% for only sedimentation. Up to 40% reduction of dissolved Cr, Cu and Pb was also observed compared to 0% for sedimentation. This study shows that coagulation may be a useful process for stormwater treatment systems when the treatment requirements are high.

2020 ◽  
Vol 12 (12) ◽  
pp. 5063 ◽  
Author(s):  
Sara Egemose ◽  
Anne B. Petersen ◽  
Melanie J. Sønderup ◽  
Mogens R. Flindt

The characteristics of stormwater need focus due to climate change. Paved areas and recipients receiving more stormwater have an enhanced need for treatment before discharge to remove suspended solids, nutrients and xenobiotics. To handle and treat stormwater efficiently, knowledge concerning first flush patterns is crucial. Therefore, we have studied 12 entire rain events and correlated water volume, suspended solids, and dissolved and particulate phosphorus to catchment characteristics and precipitation characteristics. We have mainly studied smaller rain events (average 12.6 mm), as nearly 90% of the events in the studied catchment are <10 mm. We revealed first flush tendencies in 50% of the rain events, concerning both suspended solids and phosphorus. We also found significant correlations between catchment size and discharged masses, and most importantly between precipitation patterns and discharged mass per volume. A long dry period and low amount of rain during the previous event, as well as high rain intensity, gives a high chance of first flush. We conclude that stormwater treatment should focus on the initial part of the event, especially in areas with a lack of space and/or economy to handle and treat the entire event.


2011 ◽  
Vol 255-260 ◽  
pp. 2718-2721
Author(s):  
Ru Zhang ◽  
Anthony N. Tafuri ◽  
Richard Field ◽  
Shaw L. Yu ◽  
Wen Bin Zhou ◽  
...  

Xikeng Reservoir is one of the major water supply reservoirs in Shenzhen. The water quality of Xikeng Reservoir has been poor, with much of the pollution coming from nonpoint sources. An innovative low impact development type of BMP called the BioBox was used at the Administration Building parking lot location, as a research site and demonstration project to show how small alterations to parking lot designs can dramatically decrease pollutant loads. Manual samples were collected during storm events and analyzed for total suspended solids (TSS); five-day biochemical oxygen demand (BOD5); ammonia nitrogen (NH3-N), and total phosphorus (TP). In summary, the ranges of removal rates of the BioBox are: TSS 70% - 90%; BOD5 20% - 50%, and ammonia and phosphorus 30% - 70%. The BioBox system effectively reduced the concentrations of pollutants in the parking lot runoff.


2019 ◽  
Vol 152 (Supplement_1) ◽  
pp. S88-S88
Author(s):  
Jose Jara Aguirre ◽  
Karl Ness ◽  
Alicia Algeciras-Schimnich

Abstract Introduction The CLSI EP15-A3 guideline “User Verification of Precision and Estimation of Bias” provides a simple experimental approach to estimate a method’s imprecision and bias. The objective is to determine if the laboratory precision performance of repeatability (SR) and within-laboratory imprecision (SWL) are in accordance to the manufacturer specification claims (MSCs). Objectives Evaluate the utility of the EP15-A3 protocol to verify method precision during a troubleshooting investigation and after major instrument maintenance, using a carcinoembryonic antigen (CEA) immunoassay as an example. Methods CEA was performed on the Beckman Coulter DxI (Beckman Coulter, Brea, CA). Quality control (QC) levels (L1: 2.89; L2: 21.10; L3: 39.10 ng/mL) (Bio-Rad Laboratories, Irvine, CA) were used. Each QC level was measured before and after instrument maintenance as follows: five replicates per run, one run per day, and during 5 days. Imprecision estimates (IEs) for SR (%CVR) and SWL (%CVWL) were calculated by one-way analysis of variance using Microsoft Excel Analyse-it software. Estimated imprecision was compared to MSC and desirable imprecision specifications based on biological variation (BV). Results A change in the analytical performance of CEA was detected by a decreased sigma-metric indicator. After a bias problem was ruled out, the observed %CVR for L1, L2, and L3 were 7.2%, 3.7%, and 4.8%, respectively. The %CVWL were 8.3%, 5.0%, and 5.5%, which exceeded the MSC of %CVWL~4.0% to 4.5%. After a laboratory investigation, major instrument maintenance was performed by the manufacturer. The %CVR and %CVWL estimates for L1, L2, and L3 after maintenance were 3.2%, 3.8%, 3.5% and 3.9%, 4.2%, 4.0%, respectively. After maintenance, the CEA performance was consistent with the MSC for each of the levels analyzed and within the BV impression goal of %CV ≤6.4. Conclusion CLSI EP15-A3 guideline is an alternative troubleshooting tool that can be used to investigate and verify method precision performance before and after significant instrument maintenance.


2011 ◽  
Vol 64 (8) ◽  
pp. 1692-1699 ◽  
Author(s):  
C. F. Yong ◽  
A. Deletic ◽  
T. D. Fletcher ◽  
M. R. Grace

Pervious pavements are an effective stormwater treatment technology. However, their performance under variable drying and wetting conditions have yet to be tested, particularly under a continuous time scale. This paper reports on the clogging behaviour and pollutant removal efficiency of three pervious pavement types over 26 accelerated years. These pavements were monolithic porous asphalt (PA), Permapave (PP) and modular Hydrapave (HP). Over a cycle of 13 days, the period of which was equivalent to the average annual Brisbane, Australia rainfall (1,200 mm), the pavements were randomly dosed with four different flows. Drying events of 3 h duration were simulated during each flow. Inflow and outflow samples were collected and analysed for Total Suspended Solids (TSS), Total Phosphorus (TP) and Total Nitrogen (TN). To evaluate the rate of clogging, a 1 in 5 year Brisbane storm event was simulated in the 6th, 8th, 12th, 16th, 20th and 24th week. Under normal dosing conditions, none of the pavements showed signs of clogging even after 15 years. However, under storm conditions, both PA and HP started to clog after 12 years, while PP showed no signs of clogging after 26 years. The drying and various flow events showed no effects in TSS removal, with all systems achieving a removal of approximately 100%. The average TP removal was 20% for all flows except for low flow, which had a significant amount of leaching over time. Leaching from TN was also observed during all flows except high flow. The TSS, TP and TN results observed during storm events were similar to that of high flow.


2005 ◽  
Vol 52 (12) ◽  
pp. 225-232 ◽  
Author(s):  
B.C. Lee ◽  
S. Matsui ◽  
Y. Shimizu ◽  
T. Matsuda ◽  
Y. Tanaka

We installed a new device on a paved road to treat runoff from a roadway surface. All the stormwater runoff was transferred into the device and the runoff equivalent to 10mm/hr or less was treated. The treatment method consists of sedimentation and up-flow filtration with porous polypropylene (PPL) processes. The treated runoff was discharged into the existing storm drainage pipe. The average removal efficiency of the initial runoff at the beginning of rainfall which has high pollution intensity was about 90% for SS, about 70% for COD, about 40% for total phosphorus (T-P), about 80% for Pb and Cd, about 70% for Zn, Cu, Mn and Cr, and about 60% for polycyclic aromatic hydrocarbons (PAHs). The overall removal efficiencies of the experiment that ran for four months remained &gt;60% of SS, &gt;40% of COD, &gt;60% of heavy metals, and &gt;40% of PAHs. The PPL is excellent for removing smaller size particulates of suspended solids, which originate basically from diesel exhaust, as well as larger size particulates from automobile tires, asphalt roads, and other accumulated source(s) of clay and sand, etc.


2015 ◽  
Vol 13 (4) ◽  
pp. 1029-1038 ◽  
Author(s):  
Jingfeng Fan ◽  
Hongxia Ming ◽  
Lili Li ◽  
Jie Su

The horizontal distribution and temporal variation of bacterial indicators (total coliforms (TC), fecal coliforms (FC), enterococcus (EC) and Escherichia coli (E. coli)) were investigated to identify the proper bacterial indicators for a marine bathing beach in China. Two different sampling efforts were conducted during dry weather and two large rain events at Xinghai Bathing Beach in Dalian, China. Samples were collected from three different water depths and analyzed for the four indicator bacteria. The results indicated that all four bacterial indicators exceeded the single sample standards at different levels. Specifically, the water quality exceeded the standard for TC, FC, EC and E. coli in 7%, 28%, 38% and 10% of the samples, respectively. Comparison of the rate of the indicators before and after rainfall revealed a significant increasing post-rainfall. The concentrations of bacteria differed significantly with distance from the shoreline, with knee-depth near the shore exceeding the standard most frequently. This was primarily due to contamination by excessive sewage discharge and rainfall. Based upon the concentration of indicators and exceedance rates, as well as the correlation between indicators, both EC and FC should be evaluated at the same time as fecal pollution bacterial indicators in marine bathing beaches in China.


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Miroslav Sokić ◽  
Željko Kamberović ◽  
Vesna Nikolić ◽  
Branislav Marković ◽  
Marija Korać ◽  
...  

The objects of this investigation were the comparative kinetic analysis of the NiO and NiCl2reduction by hydrogen during an induction period and elimination of the calcination during the synthesis of Ni/Al2O3catalysts. The effect of temperature and time on NiO and NiCl2reduction degrees was studied. Avrami I equation was selected as the most favorable kinetic model and used to determine activation energy of the NiO and NiCl2reduction for the investigated temperature range (623–923 K) and time intervals (1–5 minutes). The investigation enabled reaching conclusions about the reaction ability and rate of the reduction processes. Afterward, Ni/Al2O3catalysts were obtained by using oxide and chloride precursor for Ni. The catalysts were supported on alumina-based foam and prepared via aerosol route. Properties of the samples before and after low-temperature hydrogen reduction (633 K) were compared. Obtained results indicated that the synthesis of Ni/Al2O3catalysts can be more efficient if chloride precursor for Ni is directly reduced by hydrogen during the synthesis process, without the calcination step. In addition, Ni-Pd/Al2O3catalysts with different metal content were prepared by using chloride precursors. Lower reduction temperature was utilized and the chlorides were almost completely reduced at 533 K.


2016 ◽  
Vol 37 (19) ◽  
pp. 2405-2413 ◽  
Author(s):  
Lelum Duminda Manamperuma ◽  
Harsha Chandima Ratnaweera ◽  
A. Martsul

2014 ◽  
Vol 69 (8) ◽  
pp. 1751-1758 ◽  
Author(s):  
A. Hannouche ◽  
G. Chebbo ◽  
C. Joannis

A large database of continuous flow and turbidity measurements cumulating data on hundreds of rain events and dry weather days from two sites in Paris (called Quais and Clichy) and one in Lyon (called Ecully) is presented. This database is used to characterize and compare the behaviour of the three sites at the inter-events scale. The analysis is probed through three various variables: total volumes and total suspended solids (TSS) masses and concentrations during both wet and dry weather periods in addition to the contributions of diverse-origin sources to event flow volume and TSS load values. The results obtained confirm the previous findings regarding the spatial consistency of TSS fluxes and concentrations between both sites in Paris having similar land uses. Moreover, masses and concentrations are proven to be correlated between Parisian sites in a way that implies the possibility of some deterministic processes being reproducible from one catchment to another for a particular rain event. The results also demonstrate the importance of the contribution of wastewater and sewer deposits to the total events' loads and show that such contributions are not specific to Paris sewer networks.


2015 ◽  
Vol 73 (3) ◽  
pp. 636-642 ◽  
Author(s):  
Baofeng Lou ◽  
Shiyong Yin

The Three Gorges Reservoir (TGR) began to store water in 2003. The water level reached 135 m in 2003, 156 m in 2006, 172 m in 2008 and 175 m (target level) in every year from 2010 through 2013. Impacts of dams on the environment are a concern all over the world. A major concern for reservoirs is phosphorus and possible eutrophication. Therefore, total phosphorus (TP) in the TGR mainstem was determined at five stations (S1–S5) from 1998 through 2013 to investigate variations of phosphorus with water level elevations. Results revealed that a new spatial and seasonal TP distribution has occurred after the impoundment. TP levels in the reach between S3 (nearly 300 km from the dam) and S5 (near the dam) have decreased sharply compared with those before the impoundment. The reduction degree of TP in wet season was greater than in dry season. Additionally, TP spatially decreased from upstream to the dam after the impoundment. The reduction of TP levels was mainly attributed to the settling of suspended solids and adsorbed phosphorus. These findings will inform research about transport and fate of phosphorus in TGR and Yangtze River. The challenge remains to implement measures to limit the release of phosphorus from sediments.


Sign in / Sign up

Export Citation Format

Share Document