Differences in removal rates of virgin/decayed microplastics, viruses, activated carbon, and kaolin/montmorillonite clay particles by coagulation, flocculation, sedimentation, and rapid sand filtration during water treatment

2021 ◽  
pp. 117550
Author(s):  
Yoshifumi Nakazawa ◽  
Taketo Abe ◽  
Yoshihiko Matsui ◽  
Koki Shinno ◽  
Sakiko Kobayashi ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Water Treatment ◽  
Montmorillonite Clay ◽  
Sand Filtration ◽  
Removal Rates ◽  
Clay Particles ◽  
Rapid Sand Filtration

Algae as surrogate indices for the removal of Cryptosporidium oocysts by direct filtration

2002 ◽  
Vol 2 (3) ◽  
pp. 73-80 ◽  
Author(s):  
M. Akiba ◽  
S. Kunikane ◽  
H.-S. Kim ◽  
H. Kitazawa
Keyword(s):  
Water Treatment ◽  
Selenastrum Capricornutum ◽  
Sand Filtration ◽  
Removal Rates ◽  
Filtration Time ◽  
Direct Filtration ◽  
Zeta Potentials ◽  
Water Treatment Plants ◽  
Cryptosporidium Parvum Oocysts ◽  
Rapid Sand Filtration

To evaluate the appropriateness of using algae as surrogate indices for the removal of Cryptosporidium parvum oocysts in conventional water treatment by rapid sand filtration, investigations on algal removal at eight water treatment plants and laboratory experiments using three species of algae and C. parvum oocysts were conducted. From the 5 years data collected from eight water treatment plants, the algal removal showed 0.63 - 1.83 log in coagulation and 1.66 - 4.17 log in sand filtration including coagulation. In jar tests, zeta potentials of flocs at an ALT ratio of 0.05 were -8.5 mV, -8.5 mV, -7.0 mV and -10.5 mV, and the removal rates at pH 7 were 2.05 log, 1.15 log, 1.51 log and 1.49-log for Microcystis viridis, Microcystis aeruginosa, Selenastrum capricornutum and C. parvum oocysts, respectively. In direct filtration tests, the removal rates of algae and C. parvum oocysts, except for M. aeruginosa, were around 3-log during the filtration time of 15-45 minutes when the best removal occurred. S. capricornutum, out of the three species of algae, showed almost the same coagulation characteristics as C. parvum oocysts and also behaved in a filtration pattern similar to C. parvum. From these results, algae were considered useful surrogate indices for the removal of C. parvum oocysts, and S. capricornutum was thought to be an appropriate one in rapid sand filtration.

Removal characterization of 133Cs and 127I in a water treatment process using a laboratory scale experiment

2013 ◽  
Vol 13 (5) ◽  
pp. 1289-1294
Author(s):  
Hee Suk Lee ◽  
Jeongyup Lee ◽  
Byengsuk Yoon ◽  
Youjin Yim ◽  
Ilhwan Choi ◽  
...  
Keyword(s):  
Drinking Water ◽  
Activated Carbon ◽  
Water Treatment ◽  
Ion Exchange ◽  
Powdered Activated Carbon ◽  
Laboratory Scale ◽  
Radioactive Material ◽  
Radioactive Materials ◽  
Removal Rates ◽  
Exchange Method

Due to the tragic disaster that happened in Japan and crippled the Fukushima nuclear power plant, serious concerns have been raised regarding the contamination of drinking water as a result of the radioactive materials that were released. Even though the quantities of radioactive material in rain were relatively low, people were concerned about the drinking water. Therefore, there is a need to know the removal efficiency of the unit process of water treatment and to prepare a safety plan to protect the public's health from radioactive materials. In this study, the laboratory scale removal rates were estimated for the coagulation/flocculation, adsorption, and ion exchange processes. The reference standard materials which are stable elements, Cesium-133 (Cs-133) and Iodine-127 (I-127), were used for the typical and advanced water treatment processes at the laboratory scale. For the coagulation/flocculation process, three major coagulants were assessed for this process. However, the removal rates of this process were low. For the adsorption process, powdered activated carbon and zeolites were investigated. The powdered activated carbon showed insignificant removal rates for both reference materials. However, synthetic zeolite was an effective process for Cs-133, and the ion exchange method showed high removal rates for both Cs-133 and I-127.

Treatment Methods for the Removal of Off-Flavours from Heavily Polluted River Water in the Netherlands – A Review

1983 ◽  
Vol 15 (6-7) ◽  
pp. 301-310 ◽  
Author(s):  
J Hrubec ◽  
H A M de Kruijf
Keyword(s):  
Activated Carbon ◽  
The Netherlands ◽  
River Water ◽  
River Rhine ◽  
Sand Filtration ◽  
Treatment Methods ◽  
Polluted River ◽  
The North ◽  
Carbon Filtration ◽  
Rapid Sand Filtration

In The Netherlands the raw water, obtained from the heavily polluted river Rhine, has off-flavours which must be removed by using sophisticated and expensive treatment methods to be acceptable for drinking. One method consists of storage of river water in open bankside reservoirs with residence time of a few months followed by physical-chemical treatment involving coagulation, ozonation, rapid sand filtration, activated carbon filtration and disinfection. Another method used consists of pretreatment of river water by means of coagulation and rapid sand filtration followed by underground storage in the dune areas along the North Sea coast by means of artificial recharge. The water after the recharge is treated by using aeration, dosing of powdered activated carbon, rapid sand filtration and slow sand filtration. The most effective treatment processes for improvement of taste and odour are ozonation and activated carbon filtration.

scholarly journals Rapid Lava Sand Filtration for Decentralized Produced Water Treatment System in Old Oil Well Wonocolo

2019 ◽  
Vol 5 (2) ◽  
pp. 113
Author(s):  
Ekha Yogafanny
Keyword(s):  
Water Treatment ◽  
Crude Oil ◽  
Produced Water ◽  
Oil Production ◽  
Real Field ◽  
Oil Well ◽  
Sand Filtration ◽  
Turbidity Removal ◽  
Produced Water Treatment ◽  
Rapid Sand Filtration

The Cepu Block Oil Field has been traditionally extracted since 2008 by the local community in Wonocolo. The oil well-produced gas and fluids consisted of crude oil and produced water. This oil production activity discharges high amounts of produced water. The fluids have been settled down in the sedimentation tank to gain the crude oil optimally. The remaining fluid called produced water has been discharged to the surface towards the river without any further treatment.  This activity led to the deterioration of environmental quality. This study aimed to analyze the performance of produced water treatment by rapid sand filtration by measuring the degree of turbidity removal under the specific condition on a laboratory scale using lava sand. The sedimentation was conducted in 3 hours of retention time following the real field condition of the oil production process by community in one sample well. The rapid sand filtration was conducted by a fixed bed column method with 0.2 cm of grain size. The sedimentation process followed by the rapid sand filtration in produced water treatment yielded the high efficiency of turbidity removal reaching 98.65 %. The rapid sand filter also worked excellently in turbidity removal attaining 96.48 % of efficiency. These results confirmed that the sedimentation already done by the community followed by the rapid sand filtration is promising decentralized technology to be applied in a remote area such as Old Oil Wells Wonocolo regarding turbidity removal.

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