scholarly journals A Comparative Study of Water Turbidity Removal Efficiency of Anthracite and Gravel in Roughing Filter

2020 ◽  
Vol 3 (1) ◽  
pp. 42-49
Author(s):  
Bhesh Kumar Karki ◽  
Iswar Man Amatya
Keyword(s):  
Grain Size ◽  
Removal Efficiency ◽  
Filtration Rate ◽  
Cost Effective ◽  
Head Loss ◽  
Water Turbidity ◽  
Turbidity Removal ◽  
Flow Rates ◽  
Cost Effective Method ◽  
Flow Rate Change

This research was carried out to compare turbidity removal efficiency of anthracite up flow roughing filter (RF) model to gravel RF model at different flow rates. Two identical filter columns with (230*230*1570) mm3 in internal dimensions were operated at same time. Same grain size (2 - 4.75) and (4.75 - 9.5) mm were used in gravel model and anthracite model. All the sizes were achieved by properly sieving through standard sieve sizes (2, 4.75, 9.5, 12.5 and 25 mm). The study involved measuring turbidity every 2 hours and head loss once a day. Filter models were operated around 200 NTU influent turbidity until maximum allowable head loss was reached. Three sets of experiments were carried at filtration rate of .0.5 to 1.5 m/h. Anthracite model was 2.07% more efficient in terms of turbidity removal. Increasing filtration rate from 0.5 to 1.5 m/h, the effluent turbidity in gravel model increased from 24.44 to 33.52 NTU whereas that in anthracite model increased from 21.48 to 28.02 NTU and removal efficiency in anthracite model decreased from 89 to 86% while in gravel model decreased from 88 to 84%. Thus, it can be concluded that anthracite model was highly significant to removal turbidity and less affected by the flow rate change in case of efficiency. Thus, this cost-effective method can be used in context of Nepal as well.

scholarly journals The performance of sludge blanket clarifier against conventional settler under high water turbidity conditions

2018 ◽  
Vol 13 (3) ◽  
pp. 642-653 ◽  
Author(s):  
Moharram Fouad ◽  
Shaban Hassan
Keyword(s):  
Removal Efficiency ◽  
Field Data ◽  
High Water ◽  
Ease Of Use ◽  
Turbid Water ◽  
Water Turbidity ◽  
Turbidity Removal ◽  
Accumulation Pattern ◽  
Algae Removal ◽  
Sludge Accumulation

Abstract The performance of a sludge blanket clarifier was evaluated and compared to conventional settlers under high levels of turbidity and algae in the field and experimentally. Field data of sludge blanket and conventional clarifier operation were observed simultaneously for the treatment of highly turbid water. In addition, a comparison was carried out on turbidity removal efficiency, algae removal, and sludge accumulation pattern. Finally, these systems were simulated in the laboratory and operated to treat turbid water with high levels of turbidity and algae up to 80 NTU and 109cells/l respectively. Field data confirmed that the sludge blanket clarifier equipped with upper sludge cones has a high removal efficiency of turbidity and algae, ease of use and has insignificant sludge accumulation compared to the conventional settler. Further, laboratory experiments have confirmed that sludge blanket clarifier is also very effective for the treatment of high algae concentrations up to 109cells/l, with a short retention time, compared to a conventional settler, which was not effective under these conditions.

scholarly journals A comparison of different pilot constructed clarifiers with the purpose of achieving the optimum condition in turbidity removal at water treatment plants in Tehran

2017 ◽  
Vol 12 (3) ◽  
pp. 576-588 ◽  
Author(s):  
Seyed Ahmad Mirbagheri ◽  
Sima Malekmohamadi ◽  
Sheida Sohrabi Nasrabadi
Keyword(s):  
Water Treatment ◽  
Optimum Condition ◽  
Removal Efficiency ◽  
Ferric Chloride ◽  
Flow Rate ◽  
Superior Performance ◽  
Turbidity Removal ◽  
Flow Rates ◽  
Water Treatment Plants

Clarifying is one of the most crucial stages in water treatment at water treatment plants. Determining the type of the clarifier in water treatment plants and using it efficiently is necessary. In this study, a pilot is designed and constructed in which the pulsator, the superpulsator and the accelerator are simulated. For each system, turbidity removal efficiency for different influent turbidities and flow rates were studied and the optimum condition was obtained. The results showed that the superpulsator has a superior performance compared to the pulsator, and the pulsator has a superior performance compared to the accelerator and these differences are more sensible at higher flow rates. Also, the best condition for achieving the highest efficiency for the pulsator and the superpulsator is determined to be at flow rate 3 lit/min for an initial turbidity of 2,500 NTU with alum as the coagulant and the highest efficiency for the accelerator is determined to be at flow rate 3 lit/min for an initial turbidity of 2,500 NTU with ferric chloride as the coagulant. Comparing the turbidity removal efficiency shows that for 67% of the cases, ferric chloride has a better performance as the coagulant compared to alum and increasing the influent turbidity leads to an increase in the removal efficiency. Furthermore, three water treatment plants located in Tehran were studied and their characteristics were compared and suggestions were made to enhance their qualities.

The Effect of Variation in Cone Position Heigth on Raw Water Turbidity Removal in Sedimentation Unit Continuous Discharge Flow (CDF) Method as a New Method

2021 ◽  
Vol 20 (1) ◽  
pp. 58-64
Author(s):  
Ridwan Ridwan ◽  
Reri Afrianita ◽  
Yar Gustina
Keyword(s):  
Removal Efficiency ◽  
Rank Correlation ◽  
New Method ◽  
Raw Water ◽  
Water Turbidity ◽  
Turbidity Removal ◽  
Spearman’S Rank Correlation ◽  
Optimum Position ◽  
Exhaust Stream ◽  
Laboratory Scale Reactor

Unit sedimentasi metode continuous discharges flow (CDF) adalah metode baru dalam menyisihkan kekeruhan yang menggunakan prinsip tangki bocor secara kontinu dan terkendali. Perubahan ketinggian posisi cone dari dasar zona pengendapan ke bagian atas, dapat memperkecil jarak antara sumber aliran buang akibat bocor yang berasal dari cone sebagai sumber gaya baru yang bekerja terhadap flok, dan pada akhirnya meningkatkan efisiensi penyisihan kekeruhan. Penelitian ini bertujuan untuk menganalisis efisiensi penyisihan kekeruhan air baku pada 3 variasi ketinggian posisi cone di zona pengendapan. Penelitian menggunakan reaktor skala laboratorium kapasitas 240 L/jam yang terdiri dari unit koagulasi terjunan, flokulasi baffle channel dan sedimentasi metode CDF. Unit sedimentasi metode CDF yang digunakan adalah CDF 6% dengan variasi ketinggian posisi cone 0 m, 0,33 m dan 0,66 m dari dasar zona pengendapan. Air baku yang digunakan adalah Sungai Batang Kuranji Kota Padang dengan kekeruhan 25,876 – 26,012 NTU dan tawas sebagai koagulan dalam proses koagulasi. Hasil penelitian menunjukkan efisiensi penyisihan kekeruhan pada ketinggian posisi cone 0 m, 0,33 m dan 0,66 m secara berurutan adalah sebesar 82,88%, 83,86% dan 84,60%. Ketinggian posisi cone 0,66 m dari dasar zona pengendapan adalah posisi optimum dengan efisiensi penyisihan kekeruhan 1,72% lebih besar dari posisi cone di dasar zona pengendapan, yaitu 0 m. Analisis pengaruh ketinggian posisi cone terhadap penyisihan kekeruhan menggunakan korelasi Rank Spearman, menunjukkan pengaruh yang sangat kuat, semakin tinggi posisi cone semakin besar efisiensi penyisihan. Bilangan Reynolds (NRe)dan bilangan Froude (NFr) pada aliran buang ini secara berurutan adalah 23,83 dan 9,33x10-4. ABSTRACTThe continuous discharges flow (CDF) sedimentation unit is a new method for removing turbidity using the principle of a continuous and controlled leaking tank. Changes in the height of the cone position from the bottom of the settling zone to the top, can reduce the distance between the exhaust flow sources due to leakage from the cone as a new force source acting on the floc, and ultimately increase the efficiency of turbidity removal. This study aims to analyze the efficiency of raw water turbidity removal at 3 variations in the height of the cone position in the settling zone. The study used a laboratory-scale reactor with a capacity of 240 L/hour consisting of a plunge coagulation unit, baffle channel flocculation, and CDF sedimentation method. The sedimentation unit for the CDF method used is 6% CDF with variations in the height of the cone position 0 m, 0.33 m, and 0.66 m from the bottom of the settling zone. The raw water used is Sungai Batang Kuranji, Padang City with a turbidity of 25.875 – 26.012 NTU and alum as a coagulant in the coagulation process. The results showed that the efficiency of removal of turbidity at the height of the cone 0 m, 0.33 m, and 0.66 m respectively was 82.88%, 83.86%, and 84.60%. The height of the cone position 0.66 m from the bottom of the settling zone is the optimum position with a turbidity removal efficiency of 1.72% greater than the cone position at the bottom of the settling zone, which is 0 m. Analysis of the effect of the height of the cone position on the removal of turbidity using Spearman's Rank correlation showed a very strong influence, the higher the cone position the greater the removal efficiency. Reynolds number (NRe) and Froude number (NFr) in this exhaust stream are 23.83 and 9.33x10-4, respectively.

scholarly journals Application of multi-step approach for comprehensive identification of microplastic particles in diverse sediment samples

2020 ◽  
Author(s):  
Olga Konechnaya ◽  
Christina Schwanen ◽  
Jan Schwarzbauer
Keyword(s):  
Grain Size ◽  
Organic Matter ◽  
Organic Matter Content ◽  
Cost Effective ◽  
Matter Content ◽  
Sediment Samples ◽  
Pollution Levels ◽  
Remediation Strategies ◽  
Cost Effective Method ◽  
Contamination Levels

Abstract The tremendous increase of plastic production, its intensive usage in packaging, as transport material and the insufficient management of plastic garbage lead to a rise of microplastic particles as anthropogenic contaminant in our environment. To develop appropriate management and remediation strategies for this global pollution problem, reliable and consistent analytical procedures for measuring plastics in the complex matrices need to be designed. The applicability of an easy, robust and fast multi-step approach was tested on three sediment samples from riverine, beach and backwater areas of varying origin, grain size and organic matter content is reported here. The optimized method included grain size fractionation, density separation and μ-FTIR analyses. Identification was based on two complementary methods of μ -FTIR measurements, the Image mode for small microplastics (<1 mm) and the ATR method for bigger (1–5 mm) particles. The analyses revealed the identification of several polymers in various grain sizes at different pollution levels. Major findings are the dominance of PET particles and the highest frequency of microplastic particles in the midsize fraction of 100–500 μm. Generally, the method was able to reliably detect microplastic particles in several grain size fractions and down to very low contamination levels of approximately. ten particles per 50 g of sediments with different organic matter content and various grain size characteristics. Moreover, the presented multi-step approach represents a fast, easy and less cost-effective method as alternative to more expensive and time-consuming methods.

Power earth auger modification for waste extraction from pit latrines

2013 ◽  
Vol 4 (1) ◽  
pp. 72-80 ◽  
Author(s):  
Tate Weston Rogers ◽  
Francis L. de los Reyes ◽  
Walter J. Beckwith ◽  
Robert C. Borden
Keyword(s):  
Solid Waste ◽  
Low Cost ◽  
Hydraulic Drive ◽  
Liquid Waste ◽  
Cost Effective ◽  
Solid Material ◽  
Field Testing ◽  
Flow Rates ◽  
Low Viscosity ◽  
Cost Effective Method

The extraction auger was developed to meet the need for a low cost, effective method to empty pit latrines in difficult to access locations. The basic design consists of a motor that rotates an auger inside a pipe, lifting waste from a pit and depositing it into containers through a wye fitting at the top of the device. Laboratory testing of the auger showed increases in flow rates with increasing auger rotational speed and waste viscosity. An auger with an external hydraulic drive was capable of lifting dairy waste over 2.5 m, at flow rates of over 125 liters per minute. Field-testing showed the equipment was effective at lifting medium viscosity wastes containing a mixture of liquid and solid material. However, the auger was not effective in removing low viscosity, liquid waste that would flow backward down the auger reducing lifting efficiency. The auger was capable of drilling into dense solid waste, forming a ‘posthole’ in the waste. However, since the dense solid waste would not flow towards the auger intake, actual waste removal from the pit was limited. Improved methods are needed to mix liquid and solid waste in pits prior to removal with the extraction auger or other technologies.

Experimental study on non-woven filamentous fibre micro-filter with high filtration speed

2015 ◽  
Vol 71 (9) ◽  
pp. 1414-1422 ◽  
Author(s):  
Siping Niu ◽  
Kisoo Park ◽  
Heidi B. Guerra ◽  
Youngchul Kim
Keyword(s):  
Filtration Rate ◽  
Experimental Studies ◽  
Head Loss ◽  
High Rate ◽  
High Porosity ◽  
Raw Water ◽  
Water Turbidity ◽  
Filter Performance ◽  
Filter Process ◽  
Filter Aid

A laboratory study was undertaken to pursue the filter performance of a micro-filter module employing highly porous fibre media under a high filtration rate (≥1,500 m/day), faster than that of any conventional filter process. The effects of filtration rate, head loss, raw water turbidity, and filter aid chemicals on filter performance were analysed. In spite of the extremely high filtration rate, the filter achieved an attractive efficiency, reducing the raw water turbidity by over 80%. As with other filter systems, the filter aid used ((polyaluminium chloride (PAC)) greatly affected the performance of this particular fibre filter. Long-term repetitive runs were additionally carried out to confirm the reproducibility of the filter performance. Also, a comparison was carried out with other high-rate filter systems which are either being tested for use in experimental studies, or are already commercially available. This study reveals that the filter performance under a high filtration speed is still attractive especially as PAC is used. Due to the high porosity of the fibre, the filter had small head loss even though the filtration rate was high. These results ascertain that it is possible to operate the filters with high filtration rate achieving reliable treatment performance.

scholarly journals Biopurification of Oligosaccharides by Immobilized Kluyveromyces Lactis

2019 ◽  
Vol 9 (14) ◽  
pp. 2845
Author(s):  
In-Seok Yeo ◽  
Yeo-Jin Yoon ◽  
Nari Seo ◽  
Hyun Joo An ◽  
Jae-Han Kim
Keyword(s):  
Removal Efficiency ◽  
Immune Cell ◽  
Immobilized Cells ◽  
Kluyveromyces Lactis ◽  
Continuous Process ◽  
Cost Effective ◽  
Alginate Beads ◽  
Milk Oligosaccharides ◽  
Cost Effective Method ◽  
Microbial Catalysts

Oligosaccharides with diverse and complex structures such as milk oligosaccharides have physiological functions including modulating intestinal microbiota or stimulating immune cell responses. However, milk carbohydrates include about 40–50% of lactose which requires a cost-effective method to separate. We developed a new method to purify the oligosaccharides from carbohydrate mixtures such as human milk oligosaccharides (HMOs) and galactooligosaccharides (GOSs) by exploiting immobilized Kluyveromyces lactis as microbial catalysts. Evaluation of media components exhibited no significant differences in the lactose removal efficiency when nutrient-rich media, minimal salt media, and distilled water without any media components were used. With the immobilization on alginate beads, the lactose removal efficiency was increased 3.4 fold compared to that of suspension culture. When the immobilized cells were reused to design a continuous process, 4 h of pre-activation enhanced the lactose eliminating performance 2.5 fold. Finally, immobilized K. lactis was used as microbial catalysts for the biopurification of HMOs and GOSs, and lactose was effectively removed without altering the overall distribution of oligosaccharides.

CAD Of Anticorrosive Protection Of Steel Structures

2019 ◽  
pp. 18-23
Keyword(s):  
Protective Coating ◽  
Computer Aided Design ◽  
Steel Structures ◽  
Cost Effective ◽  
Operating Conditions ◽  
Computational Tool ◽  
Protection Method ◽  
Cost Effective Method ◽  
The Cost ◽  
Aided Design

The choice of cost-effective method of anticorrosive protection of steel structures is an urgent and time consuming task, considering the significant number of protection ways, differing from each other in the complex of technological, physical, chemical and economic characteristics. To reduce the complexity of solving this problem, the author proposes a computational tool that can be considered as a subsystem of computer-aided design and used at the stage of variant and detailed design of steel structures. As a criterion of the effectiveness of the anti-corrosion protection method, the cost of the protective coating during the service life is accepted. The analysis of existing methods of steel protection against corrosion is performed, the possibility of their use for the protection of the most common steel structures is established, as well as the estimated period of effective operation of the coating. The developed computational tool makes it possible to choose the best method of protection of steel structures against corrosion, taking into account the operating conditions of the protected structure and the possibility of using a protective coating.

Uncertainty in air stripping tower design: implications of the air-to-water ratio

2001 ◽  
Vol 1 (4) ◽  
pp. 177-184
Author(s):  
B.I. Dvorak ◽  
J.W. Schauble
Keyword(s):  
Mass Transfer ◽  
Removal Efficiency ◽  
Cost Effective ◽  
Air Stripping ◽  
Henry's Constant ◽  
True Value ◽  
Risk Of Failure ◽  
Process Failure ◽  
Removal Efficiencies ◽  
Water Ratio

Environmental engineers are frequently faced with uncertainty in making design decisions because the true value of many process parameters is unknown. In this study, the design of countercurrent air stripping towers was modeled using fuzzy numbers, taking into account uncertainties in mass transfer and Henry's constant. It was found that, in addition to cost, the risk of failure is an important design consideration for stripping tower design. A significant over-design is both cost-effective and results in less risk of design failure. The air-to-water ratio that yielded the least risk of failure switched from low to high as the removal efficiency of the tower increased. An important result is that at lower removal efficiencies, tower design and operation is most sensitive to uncertainties in mass transfer and at higher removal efficiencies, tower design and operation is most sensitive to uncertainties in Henry's constant . The implication is that low air-to-water ratios are best when the regulatory target removal efficiency is low and/or when the uncertainty in the value of the contaminant's Henry's constant is larger than the uncertainty in the mass transfer coefficient value. Otherwise a high air-to-water ratio results in the least risk of process failure.

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