Current Progress on Removal of Recalcitrance Coloured Particles from Anaerobically Treated Effluent Using Coagulation–Flocculation

Trends toward closure of white water recirculation loops in papermaking often lead to a need for system modifications. We conducted a pilot-scale study using pulsed electrocoagulation technology to treat the effluent of an old corrugated containerboard (OCC)-based paper mill in order to evaluate its treatment performance. The operating variables were a current density of 0–240 A/m2, a hydraulic retention time (HRT) of 8–16 min, and a coagulant (anionic polyacrylamide) dosage of 0–22 mg/L. Water quality indicators investigated were electrical con-ductivity, suspended solids (SS), chemical oxygen demand (COD), and true color. The results were encouraging. Under the operating conditions without coagulant addition, the highest removals for conductivity, SS, COD, and true color were 39.8%, 85.7%, 70.5%, and 97.1%, respectively (with an HRT of 16 min). The use of a coagulant enhanced the removal of both conductivity and COD. With an optimal dosage of 20 mg/L and a shortened HRT of 10 min, the highest removal achieved for the four water quality indicators were 37.7%, 88.7%, 74.2%, and 91.7%, respectively. The water qualities thus attained should be adequate to allow reuse of a substantial portion of the treated effluent as process water makeup in papermaking.

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Optimisation of coagulation and chlorination in drinking water treatment: laboratory and full-scale studies

Water Science & Technology Water Supply ◽

10.2166/ws.2002.0055 ◽

2002 ◽

Vol 2 (2) ◽

pp. 131-137

Author(s):

N.D. Basson ◽

C.F. Schutte

Keyword(s):

Water Quality ◽

Large Fraction ◽

Drinking Water Treatment ◽

Agricultural Runoff ◽

Treatment Costs ◽

Full Scale ◽

Raw Water ◽

Activated Carbon Adsorption ◽

Treated Effluent ◽

Quality Optimisation

The paper deals with laboratory and full-scale studies aimed at optimising treatment processes at the Balkfontein plant of Sedibeng Water in South Africa. The raw water is highly eutrophic and contains a large fraction of treated effluent from domestic and industrial sources as well as agricultural runoff. The eutrophic nature and changing raw water quality give rise to many operational difficulties and high treatment costs as well as problems with the final water quality. Optimisation of the coagulation and chlorination processes was seen as a cheaper solution to these problems than to install advanced processes such as ozonation and activated carbon adsorption that would add greatly to treatment costs. The laboratory studies indicated that through optimisation of coagulation-flocculation and by replacement of pre-chlorination by intermediate chlorination (after primary sedimentation) most of the treatment problems could be solved and final water of the required quality produced without a large increase in treatment costs.

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Water Quality Aspects of the Nakdong Estuary Barrage

Water Science & Technology ◽

10.2166/wst.1984.0057 ◽

1984 ◽

Vol 16 (1-2) ◽

pp. 243-252 ◽

Cited By ~ 1

Author(s):

J W van Sluis ◽

L Lijklema

Keyword(s):

Water Quality ◽

Water Quality Management ◽

Sewage Treatment ◽

Large River ◽

Model Verification ◽

Nakdong River ◽

Treated Effluent ◽

Quality Aspects ◽

The Nakdong River ◽

Few Data

As a result of the construction of a barrage in the estuary of the Nakdong river the size of the estuary will be considerably reduced. In addition, a large river reservoir is created upstream of the barrage. Main points of interest are the effects of the discharge of raw sewage and treated effluent into the Nakdong river on the water quality in the projected reservoir and the water quality forecasts for the remaining part of the estuary, in relation with the existing plans for sewerage and sewage treatment for the city of Busan. In addition, measures to reduce the effects of the barrage and the outline of a water quality management programme are presented. Special consideration is given to the methodological aspects of the water quality study, i.e. the selection and use of mathematical models in a situation where input data are rather uncertain and only very few data for parameter estimation and model verification are available.

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Public health implications of waste water reuse for fish production

Water Science & Technology ◽

10.2166/wst.1995.0425 ◽

1995 ◽

Vol 32 (11) ◽

pp. 145-152 ◽

Cited By ~ 7

Author(s):

M. El-S. Easa ◽

M. M. Shereif ◽

A. I. Shaaban ◽

K. H. Mancy

Keyword(s):

Public Health ◽

Waste Water ◽

Water Reuse ◽

Monitoring Program ◽

Health And Safety ◽

Fish Farming ◽

Human Consumption ◽

Fresh Water Fish ◽

Adverse Health Effects ◽

Treated Effluent

Public health and safety concerns have traditionally been the main reasons for resisting waste water reuse for fish farming. Potential adverse health effects in such applications could be avoided if the waste is sufficiently treated before reuse. In a full scale demonstration study in Suez, Egypt, about 400 m3/d of raw sewage were treated using a multi-compartment stabilization pond system, for a total residence time from 21-26 days. The treated effluent conformed to WHO guidelines and was used for rearing two types of local fish (tilapia and gray mullet). The produced fish were subjected to an extensive monitoring program. Bacteriological examination revealed that in all samples the fish muscles were free of bacterial contaminants. Nevertheless, low levels of Escherichia coli andAeromonas hydrophila, were isolated from the surface of the fish. Salmonellae, shigellae and staphylococcus aureus were absent from the surface of all the fish sampled. In addition, toxic metals (Pb, Cu, Zn, and Cd) were found to be at much lower levels than the international advisory limits for human consumption. It is concluded that fish reared in the treated effluent at Suez Experimental Station is (a) suitable for marketing for human consumption, and (b) it's quality is equal or better than fresh water fish in Egypt.

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Chemical characterization and biotreatability of effluents from an integrated alkaline-peroxide mechanical pulping/machine finish coated (APMP/MFC) paper mill

Water Science & Technology ◽

10.2166/wst.1997.0470 ◽

1997 ◽

Vol 35 (2-3) ◽

pp. 7-14 ◽

Cited By ~ 3

Author(s):

A. Schnell ◽

M. J. Sabourin ◽

S. Skog ◽

M. Garvie

Keyword(s):

Activated Sludge ◽

Aquatic Toxicity ◽

Wood Chip ◽

Chemical Characterization ◽

Toxicity Testing ◽

Sampling Period ◽

Paper Mill ◽

Alkaline Peroxide ◽

Conventional Activated Sludge ◽

Treated Effluent

As part of an extensive audit of the Alkaline-Peroxide Mechanical Pulping (APMPTM) plant at the Malette Quebec Inc. mill in St. Raymond, Que., effluents were sampled from various stages of the process for comprehensive chemical characterizations, aquatic toxicity testing and anaerobic biotreatability assessments. In addition, untreated and secondary treated combined effluent from the integrated paper mill were sampled to determine the effectiveness of a conventional activated sludge process at the mill site. During the one-day sampling period, the APMP plant processed a mixed wood furnish consisting of 50% spruce/balsam fir and 50% aspen, with a chemical charge of 3.5% sodium hydroxide and 3.8% hydrogen peroxide on oven-dry fibre, while the Machine Finish Coated (MFC) paper production rate was 100 odt/d (oven dry metric tonnes per day). Measured production-specific contaminant discharge loadings from the novel APMP process were 56 kg BOD5/odt and 155 kg COD/odt in a combined effluent flow of 28 m3/odt. Sources of process effluent were chip washing, three stages of wood chip pretreatment and chemical impregnation (i.e., Impressafiner stages), interstate washing and pulp cleaning. The three Impressafiner pressates were found to be the most concentrated (i.e., 12-26 g COD/L) and toxic streams. Microtox testing of the pressates revealed EC50 concentrations of 0.07-0.34% v/v. The warm and concentrated effluents generated by the non-sulphur APMP process were found to be highly amenable to anaerobic degradation as determined by batch bioassay testing. Filterable BOD5 and COD(f) of the process effluents were reduced by 87-95% and 70-77%, respectively, with corresponding theoretical methane yields being attained. Acid-soluble dissolved lignin compounds exhibited biorecalcitrance, as revealed by limited removals of 34-55%, and were the main constituents contributing to residual COD(f), while resin and fatty acids (RFA) were reduced by 80-94%. The conservatively operated full scale activated sludge treatment process achieved a similar high 74% COD(f) removal from the whole mill effluent, while BOD5 and RFA reductions were virtually complete and the treated effluent was non-toxic, as measured by Microtox.

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Activated sludge plant facing grape harvest period – a case study

Water Science & Technology ◽

10.2166/wst.1996.0259 ◽

1996 ◽

Vol 34 (11) ◽

pp. 25-32 ◽

Cited By ~ 3

Author(s):

P. Chudoba ◽

R. Pujol

Keyword(s):

Activated Sludge ◽

Municipal Wastewater ◽

Treatment Plant ◽

Organic Pollution ◽

Worst Case ◽

Wine Production ◽

Original Solution ◽

Treated Effluent ◽

Nominal Capacity ◽

Sludge Settleability

Most of municipal activated sludge plants located in wine production regions receive winery wastewaters during the grape harvest period which lasts usually only a few weeks. A drastic increase in organic pollution (COD, BOD) during this period generates a temporary overloading, resulting very often in biological problems such as decreased sludge settleability, sludge floc disintegration, increased SS concentration in treated effluent and in the worst case a complete plant failure. In order to work satisfactorily even during those temporary overloading periods, the plant has to be oversized. This strategy is rather costly, because such a plant has to run below its nominal capacity during a major part of the year. An original solution has been proposed and successfully tested at a municipal wastewater treatment plant in Eguisheim, France. The proposed technique is based on the addition of a mineral material with a low particle size, whose presence positively influences the physical behaviour of the sludge and will allow the nominal capacity of the plant to be surpassed without any important modification. The modification of the sludge structure around the added powdered material improved significantly the sludge settleability (DSVI< 160 ml/g) and enabled the plant to treat organic pollution several times higher than the nominal level.

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Benthic community populations near two adjacent northern pulpmill discharges

Water Science & Technology ◽

10.2166/wst.1997.0563 ◽

1997 ◽

Vol 35 (2-3) ◽

pp. 381-388 ◽

Cited By ~ 1

Author(s):

G. P. Thomas ◽

N. Munteanu

Keyword(s):

Benthic Community ◽

Ecological Model ◽

Relative Proportion ◽

Benthic Invertebrate ◽

Treated Effluent ◽

Spatial Confounding ◽

Spatial Approach ◽

Pulp And Paper Effluent ◽

Taxonomic Groups ◽

Benthic Invertebrate Communities

Benthic invertebrate communities were investigated as part of the federal Environmental Effects Monitoring programs conducted as required by the amended Pulp and Paper Effluent Regulations (PPER) of the federal Fisheries Act. A Refiner Mechanical (RMP) and larger Kraft pulpmill, both situated on a northern, BC reservoir, discharge secondary-treated effluent within 5 km of each other. Efforts to independently distinguish potential effects associated with these individual discharges were complicated by the proximity of the diffusers, their location within a complex ecological region of a reservoir, and the presence of temporal and spatial confounding influences. A comprehensive examination of the benthic community structure involved the combined assessment of several endpoints (total population numbers, relative proportion of taxonomic groups, and species richness). A tiered, spatial approach, based on a reservoir ecological model (Thornton et al., 1981), was adapted to assess and distinguish community structures and reservoir- and mill-related influences. Results suggested that effects associated with the two different mills could be distinguished based on subtle and distinct differences in benthic community profiles.

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Municipal wastewater treatment with pond–constructed wetland system: a case study

Water Science & Technology ◽

10.2166/wst.2005.0491 ◽

2005 ◽

Vol 51 (12) ◽

pp. 325-329 ◽

Cited By ~ 18

Author(s):

X. Wang ◽

X. Bai ◽

J. Qiu ◽

B. Wang

Keyword(s):

Constructed Wetland ◽

Municipal Wastewater ◽

Municipal Wastewater Treatment ◽

Oxidation Pond ◽

System A ◽

Treated Effluent ◽

Wetland System ◽

Oxidation Ponds ◽

Better Than

The performance of a pond–constructed wetland system in the treatment of municipal wastewater in Kiaochow city was studied; and comparison with oxidation ponds system was conducted. In the post-constructed wetland, the removal of COD, TN and TP is 24%, 58.5% and 24.8% respectively. The treated effluent from the constructed wetland can meet the Chinese National Agricultural and Irrigation Standard. The comparison between pond–constructed wetland system and oxidation pond system shows that total nitrogen removal in a constructed wetland is better than that in an oxidation pond and the TP removal is inferior. A possible reason is the low dissolved oxygen concentration in the wetland. Constructed wetlands can restrain the growth of algae effectively, and can produce obvious ecological and economical benefits.

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An overview of the Central Queensland University self-contained evapotranspiration beds

Water Science & Technology ◽

10.2166/wst.2005.0376 ◽

2005 ◽

Vol 51 (10) ◽

pp. 273-281 ◽

Cited By ~ 4

Author(s):

B. Kele ◽

D.J. Midmore ◽

K. Harrower ◽

B.J. McKennariey ◽

B. Hood

Keyword(s):

Environmental Health ◽

Citrus Fruit ◽

Nutrient Deficiencies ◽

Faecal Coliforms ◽

Trial Site ◽

Treated Effluent ◽

Microbial Analysis ◽

Reuse System ◽

Over Time

The Central Queensland University (CQU) has championed a self-contained concrete lined evapotranspiration channel. Any non-transpired effluent returns to a holding tank and is recirculated through the evapotranspiration channel until it is used. This paper examines the results from the Rockhampton trial site. Nutrient ions in the effluent were quantified over time and found not to accumulate in solution. Microbial analysis of the treated effluent was performed and was found to be within the ranges required by the relevant legislative codes. Citrus fruit grown in the evapotranspiration channel were sampled and no elevated levels of faecal coliforms were recorded. Macronutrients and micronutrients of the soil in the channels were measured over a 5-year period. No toxic accumulations or nutrient deficiencies in the soil occurred. Levels of salinity and sodicity in the evapotranspiration channel soil were quantified. Salinity rose slightly, as did sodium. Concentrations of salts and sodium did not reach unsustainable levels. The aim of the trial was to develop an on-site treatment and reuse system that is sustainable and protects public and environmental health.

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Post-treatment of tannery wastewater using pilot scale horizontal subsurface flow constructed wetlands (polishing)

Water Science & Technology ◽

10.2166/wst.2017.613 ◽

2017 ◽

Vol 77 (4) ◽

pp. 988-998 ◽

Cited By ~ 2

Author(s):

Tadesse Alemu ◽

Andualem Mekonnen ◽

Seyoum Leta

Keyword(s):

Removal Efficiency ◽

Batch Reactor ◽

Subsurface Flow ◽

Oxygen Demand ◽

Pilot Scale ◽

Surface Flow ◽

Tannery Wastewater ◽

Treated Effluent ◽

Horizontal Subsurface Flow ◽

Pollutants Removal

Abstract In the present study, a pilot scale horizontal subsurface flow constructed wetland (CW) system planted with Phragmites karka; longitudinal profile was studied. The wetland was fed with tannery wastewater, pretreated in a two-stage anaerobic digester followed by a sequence batch reactor. Samples from each CW were taken and analyzed using standard methods. The removal efficiency of the CW system in terms of biological oxygen demand (BOD), chemical oxygen demand (COD), Cr and total coliforms were 91.3%, 90%, 97.3% and 99%, respectively. The removal efficiency for TN, NO3− and NH4+-N were 77.7%, 66.3% and 67.7%, respectively. Similarly, the removal efficiency of SO42−, S2− and total suspended solids (TSS) were 71.8%, 88.7% and 81.2%, respectively. The concentration of COD, BOD, TN, NO3−N, NH4+-N, SO42 and S2− in the final treated effluent were 113.2 ± 52, 56 ± 18, 49.3 ± 13, 22.75 ± 20, 17.1 ± 6.75, 88 ± 120 and 0.4 ± 0.44 mg/L, respectively. Pollutants removal was decreased in the first 12 m and increased along the CW cells. P. karka development in the first cell of CW was poor, small in size and experiencing chlorosis, but clogging was higher in this area due to high organic matter settling, causing a partial surface flow. The performance of the pilot CW as a tertiary treatment showed that the effluent meets the permissible discharge standards.

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