scholarly journals Innovative Biological Treatment Processes for Wastewater in Canada

2003 ◽  
Vol 38 (2) ◽  
pp. 243-265 ◽  
Author(s):  
Catherine N. Mulligan ◽  
Bernard F. Gibbs
Keyword(s):  
Biological Treatment ◽  
Waste Treatment ◽  
Oil Spills ◽  
Metal Removal ◽  
Oxygen Demand ◽  
High Rate ◽  
Future Research ◽  
New Developments ◽  
Treatment Processes ◽  
Stage Of Development

Abstract Biological treatment of wastewater has been employed successfully for many types of industries. Aerobic processes have been used extensively. Production of large amounts of sludge is the main problem and methods such as biofilters and membrane bioreactors are being developed to combat this phenomenon. Anaerobic waste treatment has undergone significant developments and is now reliable with low retention times. The UASB, the original high rate anaerobic reactor, is now becoming less popular than the EGSB reactor. New developments such as the Annamox process are highly promising for nitrogen removal. For metal removal, processes such as biosorption and biosurfactants combined with ultrafiltration membranes are under development. Biosurfactants have also shown promise as dispersing agents for oil spills. If space is available, wetlands can be used to reduce biological oxygen demand (BOD), total suspended solids (TSS), nutrients and heavy metals. These innovative processes are described in this paper in terms of applications, the stage of development, and future research needs particular to Canada.

The organic output from mechanical–biological treatment plants as a source of microplastics: Mini-review on current knowledge, research methodology and future study perspectives

2021 ◽  
pp. 0734242X2098391
Author(s):  
Anastasiia Sholokhova ◽  
Gintaras Denafas ◽  
Valeriy Mykhaylenko
Keyword(s):  
Future Study ◽  
Biological Treatment ◽  
Waste Treatment ◽  
Scientific Literature ◽  
Current Knowledge ◽  
Future Research ◽  
Research Needs ◽  
Plastic Pollution ◽  
Treatment Processes ◽  
The World

Plastic pollution is one of the biggest environmental problems facing the world. In recent years, microplastics, polymer particles from 1  µm to 5 mm, have been getting much attention. The presence of microplastics has already been confirmed in aquatic and marine ecosystems, soil, atmosphere, biota, and others. The organic output from mechanical–biological treatment (MBT) plants was added to the list of microplastics sources only recently. However, according to preliminary estimates, it may be the second-largest source of microplastics. This article presents an overview of already published investigations on this microplastics source and explains the supposed pathway of microplastics in the MBT plants. The main waste treatment processes that can affect the amount of microplastics in the organic output have been identified as shredding, sieving and, to a lesser extent, aerobic or anaerobic processing. This mini-review also includes methods used in the scientific literature for microplastics extraction, purification, and identification in organic-rich samples, their advantages and limitations. Particular attention is paid to the methods of identifying the small microplastics, less than 1 mm, since the methods for particles 1−5 mm have been more extensively studied. Furthermore, future research needs are highlighted.

The Characteristics of Community Wastewater Biological Treatment Processes in Taiwan

1986 ◽  
Vol 18 (7-8) ◽  
pp. 289-296
Author(s):  
C. F. Ouyang ◽  
T. J. Wan
Keyword(s):  
Biological Treatment ◽  
Wastewater Treatment Plants ◽  
Oxygen Demand ◽  
Field Investigation ◽  
Oxidation Ditch ◽  
Trickling Filter ◽  
Rotating Biological Contactor ◽  
Treatment Processes ◽  
Treatment Characteristics ◽  
Sludge Thickening

This study investigated and compared the treatment characteristics of three different kinds of biological wastewater treatment plants (including rotating biological contactor, trickling filter and oxidation ditch) which are currently operated in Taiwan. The field investigation of this study concentrated on the following items: the performance of biological oxygen demand (BOD) and suspended solids (SS) removal; the sludge yield rate of BOD removal; the settleability of sludge solids; the properties of sludge thickening; the power consumption and land area requirement per unit volume of wastewater. Finally, based on the results of the field investigation, a comparison of the treatment characteristics of the three different biological treatment processes was evaluated.

Modeling Mass Transfer in Biological Wastewater Treatment Processes

1986 ◽  
Vol 18 (6) ◽  
pp. 35-45 ◽  
Author(s):  
John C. Kissel
Keyword(s):  
Mass Transfer ◽  
Computer Simulation ◽  
Wastewater Treatment ◽  
Biological Treatment ◽  
Process Models ◽  
High Rate ◽  
Biological Wastewater Treatment ◽  
Trickling Filter ◽  
Treatment Processes ◽  
Individual Effects

Parameters characterizing intrasolid, liquid/solid, and gas/liquid mass transport phenomena in biological treatment systems are required if mass transfer is to be included in process models. Estimates of such parameters are presented and discussed. Collective and individual effects of mass transfer resistances are illustrated by computer simulation of a high-rate trickling filter.

scholarly journals Short investigation on occurrence and removal of semivolatiles during wastewater treatment processes

2021 ◽  
Vol 3 (2) ◽  
pp. 130-140
Author(s):  
Maria Diana Puiu ◽  
Keyword(s):  
Wastewater Treatment ◽  
Organic Contaminants ◽  
Biological Treatment ◽  
Organic Matter Content ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Matter Content ◽  
Physical Treatment ◽  
Dissolved Air Flotation ◽  
Treatment Processes

The food industry wastewater is known to present a high organic matter content, due to specific raw materials and processing activities. Even if these compounds are not directly toxic to the environment, high concentrations in effluents could represent a source of pollution as discharges of high biological oxygen demand may impact receiving river's ecosystems. Identifying the main organic contaminants in wastewater samples represents the first step in establishing the optimum treatment method. The sample analysis for the non-target compounds through the GC-MS technique highlights, along with other analytical parameters, the efficiency of the main physical and biological treatment steps of the middle-size Wastewater Treatment Plant (WWTP). Long-chain fatty acids and their esters were the main abundant classes of non-target identified compounds. The highest intensity detection signal was reached by n-hexadecanoic acid or palmitic acid, a component of palm oil, after the physical treatment processes with dissolved air flotation, and by 1-octadecanol after biological treatment.

When the smoke disappears: dealing with extinguishing chemicals in firefighting wastewater

2014 ◽  
Vol 69 (8) ◽  
pp. 1720-1727 ◽  
Author(s):  
E. N. P. Courtens ◽  
F. Meerburg ◽  
V. Mausen ◽  
S. E. Vlaeminck
Keyword(s):  
Nitrogen Removal ◽  
Biological Treatment ◽  
Suspended Solids ◽  
Oxygen Demand ◽  
Batch Tests ◽  
Treatment Processes ◽  
Anammox Activity ◽  
Cost Calculations ◽  
Fire Extinction ◽  
Adequate Nutrient

Water is not enough. Nowadays, numerous chemicals are used for fire extinction. After use, however, these may unintentionally enter sewerage systems. In order to safely treat firefighting wastewater (FFWW), knowledge of the potential effects of these chemicals on biological treatment processes is essential. This study characterized and mimicked the composition of FFWW containing two powders, three foams and one foam degrader. Nitrogen (162–370 mg NH4+-N L−1) and phosphorus (173–320 mg PO43−-P L−1) concentrations exceeded discharge limits, whereas chemical and biological oxygen demand, suspended solids and detergent concentrations remained sufficiently low. Adequate nutrient removal could be obtained through FeCl3 addition and nitrification/denitrification with acetate as substrate. In batch tests, residual nitrifying activities of 84, 81, 89, 95 and 93% were observed in the presence of powders, foams, foam degrader, synthetic and real FFWW, respectively. All categories showed higher denitrification rates than the control. Although the powders at first seemed to inhibit anammox activity at 82%, after pH correction anammox was fully feasible, allowing nitrogen removal through oxygen-limited nitrification/denitrification (OLAND). Detailed cost calculations indicated that OLAND could save 11% of capital and 68% of operational costs compared to nitrification/denitrification, identifying OLAND as the most recommendable process for nitrogen removal from firefighting wastewaters.

Treatment of wine distillery wastewater by high rate anaerobic digestion

2007 ◽  
Vol 56 (2) ◽  
pp. 9-16 ◽  
Author(s):  
X.L. Melamane ◽  
R. Tandlich ◽  
J.E. Burgess
Keyword(s):  
Removal Efficiency ◽  
Biological Treatment ◽  
Oxygen Demand ◽  
Anaerobic Treatment ◽  
High Rate ◽  
High Chemical ◽  
Distillery Wastewater ◽  
The Mean ◽  
Removal Efficiencies ◽  
High Chemical Oxygen Demand

Wine distillery wastewaters (WDW) are acidic and have a high content of potential organic pollutants. This causes high chemical oxygen demand (COD) values. Polyphenols constitute a significant portion of this COD, and limit the efficiency of biological treatment of WDWs. WDW starting parameters were as follows: pH 3.83, 4,185 mg/l soluble COD (CODs) and 674.6 mg/l of phenols. During operation, amendments of CaCO3 and K2HPO4, individually or in combination, were required for buffering the digester. Volatile fatty acid concentrations were <300 mg/l throughout the study, indicating degradation of organic acids present. Mean CODs removal efficiency for the 130 day study was 87%, while the mean polyphenol, removal efficiency was 63%. Addition of 50 mg/l Fe3 +  between days 86 and 92 increased the removal efficiencies of CODs to 97% and of polyphenols to 65%. Addition of Co3 +  improved removal efficiencies to 97% for CODs and 92% for polyphenols. Optimization of anaerobic treatment was achieved at 30% WDW feed strength. Removal efficiencies of 92% and 84% were recorded at increased feed strength from days 108 to 130. High removal efficiencies of CODs and polyphenols after day 82 were attributed to the addition of macronutrients and micronutrients that caused pH stability and thus stimulated microbial activity.

Effective Removal of Mercury Ions in Aqueous Solutions: A Review

2020 ◽  
Vol 16 (3) ◽  
pp. 363-375
Author(s):  
Kang Hua ◽  
Xueliu Xu ◽  
Zhiping Luo ◽  
Dong Fang ◽  
Rui Bao ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Ion Exchange ◽  
Biological Treatment ◽  
Metal Removal ◽  
Removal Rate ◽  
Synergistic Effects ◽  
Heavy Metal Removal ◽  
Future Research ◽  
Human Beings ◽  
Fast Removal

Background: Due to its high toxicity and bioaccumulation, the existence of mercury in the environment is always a big threat to human beings. In order to control mercury pollution, scientists have put great efforts in the past decades. Methods: Precipitation, adsorption, membrane separation, biological treatment and ion exchange are reviewed as a remover for mercury removal. For each material type, we not only reported on the removal mechanism, but also discussed the best areas for it. The correlation method and step-to-step focusing method have been used for references. Conclusion: With the exploration and application of research, people have mastered a variety of mature technologies for the treatment of mercury-containing wastewater. Using inexpensive adsorbents is a cost-effective method for treating low concentrations of heavy metal wastewater. Ion exchange with a fast removal rate has been widely used in the field of heavy metal removal from wastewater. The biological treatment method can effectively treat low-concentration mercurycontaining wastewater. However, there is still a need to develop novel mercury removers with high capacity, fast removal rate, and low removal limit. Nanomaterials with a high specific surface area on substrate with synergistic effects, such as high adsorption and ion exchange, are the future research points.

Two-stage combined treatment of acid mine drainage and municipal wastewater

2013 ◽  
Vol 67 (5) ◽  
pp. 1000-1007 ◽  
Author(s):  
Dongyang Deng ◽  
Lian-Shin Lin
Keyword(s):  
Biological Treatment ◽  
Municipal Wastewater ◽  
Mine Drainage ◽  
Metal Removal ◽  
Combined Treatment ◽  
Oxygen Demand ◽  
Treatment Method ◽  
Phosphate Removal ◽  
Two Stage ◽  
Acid Mine

This study examined the feasibility of the combined treatment of field-collected acid mine drainages (AMD, pH = 4.2 ± 0.9, iron = 112 ± 118 mg/L, sulfate = 1,846 ± 594 mg/L) and municipal wastewater (MWW, avg. chemical oxygen demand (COD) = 234–333 mg/L) using a two-stage process. The process consisted of batch mixing of the two wastes to condition the mixture solutions, followed by anaerobic biological treatment. The mixings performed under a range of AMD/MWW ratios resulted in phosphate removal of 9 to ∼100%, the mixture pH of 6.2–7.9, and COD/sulfate concentration ratio of 0.05–5.4. The biological treatment consistently removed COD and sulfate by >80% from the mixture solutions for COD/sulfate ratios of 0.6–5.4. Alkalinity was produced in the biological treatment causing increased pH and further removal of metals from the solutions. Scanning electron microscopy of produced sludge with energy dispersion analysis suggested chemical precipitation and associated adsorption and co-precipitation as the mechanisms for metal removal (Fe: >99%, Al: ∼100%, Mn: 75 to ∼100%, Ca: 52–81%, Mg: 13–76%, and Na: 56–76%). The study showed promising results for the treatment method and denoted the potential of developing innovative technologies for combined management of the two wastes in mining regions.

scholarly journals Characteristics of greywater from different sources within households in a community in Durban, South Africa

2016 ◽  
Vol 7 (4) ◽  
pp. 520-528 ◽  
Author(s):  
B. F. Bakare ◽  
S. Mtsweni ◽  
S. Rathilal
Keyword(s):  
South Africa ◽  
Biological Treatment ◽  
Treatment Process ◽  
Oxygen Demand ◽  
Successful Implementation ◽  
Environment And Public Health ◽  
Treatment Processes ◽  
Physico Chemical ◽  
Significant Difference ◽  
Different Sources

The reuse of greywater is steadily gaining importance in South Africa. Greywater contains pollutants that could have adverse effects on the environment and public health if the water is not treated before reuse. Successful implementation of any greywater treatment process depends largely on its characteristics in terms of the pollutant strength. This study investigated the physico-chemical characteristics of greywater from different sources within 75 households in a community in Durban, South Africa. The study was undertaken to create an understanding of greywater quality from different sources within and between households. Greywater samples were collected from the kitchen, laundry and bathing facilities within each of the households. The samples were analysed for: pH, conductivity, turbidity, total solids, chemical oxygen demand (COD) and biological oxygen demand (BOD). There was a significant difference in the parameters analysed between the greywater from the kitchen compared with the greywater from the bathtub/shower and laundry. It was also observed that the characteristics of greywater from the different households varied considerably. The characteristics of the greywater obtained in this study suggest that the greywater generated cannot be easily treatable using biological treatment processes and/or technologies due to the very low mean BOD : COD ratio (<0.5).

scholarly journals Plankton biomass in secondary ponds treating piggery waste

2008 ◽  
Vol 51 (6) ◽  
pp. 1287-1298 ◽  
Author(s):  
Lígia Barthel ◽  
Paulo Armando Victória de Oliveira ◽  
Rejane Helena Ribeiro da Costa
Keyword(s):  
Green Algae ◽  
Waste Treatment ◽  
Oxygen Demand ◽  
Experimental Period ◽  
High Rate ◽  
Chlorella Sp ◽  
System A ◽  
Plankton Biomass ◽  
In Series ◽  
Soluble Chemical Oxygen Demand

This study aimed at analyzing the plankton biomass found in a piggery waste treatment system, composed of a high rate algal pond (HRAP), two maturation ponds (MP1, MP2) (System A) and a water hyacinth pond (WHP) (System B). The ponds were disposed in series and the study was performed for 32 weeks. The physicochemical variables monitored were: pH, temperature, dissolved oxygen, soluble chemical oxygen demand, nitrogen compounds and total phosphorus. The plankton biomass was identified at genus level and the ecology index was calculated so as to describe its development in the ponds. Results showed lower specific richness, which was associated to the mono-specific Chlorella sp population. The protozoa density was conversely proportional to the green algae density. The higher species diversity occurred in the WHP and MP2. The green algae presented high relative density (>97 %). The Jaccard index reached 100% if Chlorella sp and sometimes diatoms were found in the system's inlet and outlet. The productivity of algal biomass was lower than 10 gTSS/m²/d in the maturation ponds, which was maintained in the HRAP. The green algae coefficient of variation (CV) varied from 0 to 1.5 in the HRAP and WHP, but was constant at 0.9 to the 10th week in MP1 and around 0.5 during all the experimental period for MP2. For the chlorophyll a, this coefficient varied in all the ponds.

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