EFFECTS OF BLUE LED INSTALLED IN SLOW SAND FILTRATION PROCESS ON QUALITY OF TREATED WATER AND BIOLOGICAL FILTRATION MEMBRANE

Using small sand filets under well defined laboratory conditions, filtration experiments were performed with tap water supplemented with acetate. The objective of these experiments was to determine the effect of different acetate concentrations on (i) the removal of easily assimilable organic carbon (AOC) in the filter (ii), the clogging of the tiller and (iii) the bacteriological quality of the filtrate. The results of the experiments revealed that the reduction capacity of biological filtration processes for acetate is relatively high. Acetate removal resulted in an increased microbiological activity in the top layer (< 1cm) of the filter bed and accumulation of bacterial matter was observed at an influent AOC concentration as low as 0.005 mg of ac-C eq/l. Clogging of the filter bed occurred at an influent acetate concentration of 0.01 mg C/l. Based on these observations it was concluded that the AOC concentration of water used for infiltration in recharge wells should be less thon 0.01 mg ac-C eq/l. This level is similar to the level advised for biologically-stable drinking water. A linear relationship was found between the acetate removal in the experimental filters and the colony count in the filtrate. It was recommended that the AOC load in the final filtration process in water treatment therefore should be limited to prevent high colony counts in the filtrate, thus leading to the use of post disinfection.

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Empirical models of bio-sand filter to calculate the design parameters

Water Science & Technology Water Supply ◽

10.2166/ws.2009.228 ◽

2009 ◽

Vol 9 (6) ◽

pp. 723-734 ◽

Cited By ~ 2

Author(s):

Mohamad Ali Fulazzaky ◽

Norshuhaila Mohamed Sunar ◽

Ab Aziz Abd Latiff ◽

Amir Hashim Mohd Kassim

Keyword(s):

Empirical Models ◽

Physical Models ◽

Design Parameters ◽

Sand Filtration ◽

Process Technology ◽

Filtration Process ◽

Sand Filters ◽

Sand Filter ◽

Quality Of Water

The performance of bio-sand filters (BSF) should be monitored periodically to ensure the quality of water produced for the safety of consumers. An engineering design of BSF is proposed to achieve the desired efficacy of the treatment system. Accurate designs to achieve bio-sand filtration are not available in detail for most BSFs since present physical models were not originally able to calculate design's parameters. This paper develops the mathematical models to calculate the depth of sand filter and water velocity in operating the proposed BSF especially to remove organic and suspended matter simultaneously. Parameters in the equations are all physically meaningful, experimental data validation shows the equations remained accurate. The baseline design's parameters are analyzed to contribute to bio-sand filtration process technology. The filtration rates and depths of sand filter proposed in designing of the BSF system are justified.

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Improvement of Oxidation Pond Effluent Quality by Sand Filtration

Water Science & Technology ◽

10.2166/wst.1987.0170 ◽

1987 ◽

Vol 19 (12) ◽

pp. 355-357

Author(s):

Isao Somiya ◽

Shigeo Fujii ◽

Kaoru Takeda

Keyword(s):

Order Reaction ◽

Sand Filtration ◽

Filtration Process ◽

Oxidation Pond ◽

Effluent Quality ◽

First Order ◽

Zero Order Reaction ◽

Flow Filtration ◽

The Relationship

In this research, the sand filtration process is focused on as one of the techniques for raising the quality of oxidation pond effluent. Based on the data of down-flow filtration experiments, a mathematical model for DO and deposit is developed, and the behavior of the deposit in the sand filter is analyzed. The decomposition of the deposit follows a first-order reaction at a filtration rate higher than 5 m/day, while it follows a zero-order reaction at a rate lower than 1 m/day. From the relationship between deposit and head loss, the maximim quantity of the deposit is determined to be around 0.3 kg/m2 at the rate of 0.5-1 m/day and 0.2 kg/m2 at the rate of 5-10 m/day.

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The effect of the postharvest red and blue LED light exposure on the quality of cherry tomato

Acta Horticulturae ◽

10.17660/actahortic.2021.1329.22 ◽

2021 ◽

pp. 181-187

Author(s):

B.L. Ngcobo ◽

I. Bertling

Keyword(s):

Light Exposure ◽

Cherry Tomato ◽

Blue Led ◽

Led Light

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Simulation of a Solid Phase Cathodic Electro-Fenton Process as an Alternative for Improving the Quality of Treated Water

ECS Transactions ◽

10.1149/10101.0095ecst ◽

2021 ◽

Vol 101 (1) ◽

pp. 95-100

Author(s):

Luis Alberto Romero Orellana ◽

Mercedes Teresita Oropeza-Guzmán ◽

Paul Antonio Valle-Trujillo ◽

Yadira Gochi-Ponce

Keyword(s):

Solid Phase ◽

Fenton Process ◽

Treated Water

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Microbial water quality of treated water and raw water sources in the Harare area, Zimbabwe

Water SA ◽

10.4314/wsa.v41i5.12 ◽

2015 ◽

Vol 41 (5) ◽

pp. 691

Author(s):

Tatenda G Chirenda ◽

Sunitha C Srinivas ◽

R Tandlich

Keyword(s):

Water Quality ◽

Water Sources ◽

Raw Water ◽

Microbial Water Quality ◽

Treated Water

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Treatment of Groundwater with Slow Sand Filtration

Water Science & Technology ◽

10.2166/wst.1988.0092 ◽

1988 ◽

Vol 20 (3) ◽

pp. 141-147 ◽

Cited By ~ 6

Author(s):

T. Hatva

Keyword(s):

Biological Activities ◽

Treatment Phase ◽

Purification Process ◽

Sand Filtration ◽

Sand Filters ◽

Slow Sand Filtration ◽

Filtration Method ◽

Pre Treatment ◽

Full Scale Tests ◽

Iron Manganese

The purification process and techniques of the slow sand filtration method for treatment of groundwater was studied on the basis of pilot plant and full scale tests and studies of waterworks, to obtain guidelines for construction and maintenance. The purification process consists in general of two principal phases which are pre-treatment and slow sand filtration. Both are biological filters. The main purpose of the pre-treatment is to reduce the iron content of raw water, in order to slow down the clogging of the slow sand filters. Different types of biofilters have proved very effective in the pre-treatment phase, with reduction of total iron from 50 % to over 80 %. During the treatment, the oxidation reduction conditions gradually change becoming suitable for chemical and biological precipitation of iron, manganese and for oxidation of ammonium. Suitable environmental conditions are crucial in the oxidation of manganese and ammonium which, according to these studies, mainly occurs in slow sand filters, at the end of the process. Low water temperature in winter does not seem to prevent the biological activities connected with the removal of iron, manganese and ammonium, the chief properties necessitating treatment of groundwater in Finland.

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