Practical design of flocculator for new polymeric inorganic coagulant - PSI

2004 ◽  
Vol 4 (1) ◽  
pp. 67-75 ◽  
Author(s):  
K. Ohno ◽  
M. Uchiyama ◽  
M. Saito ◽  
T. Kamei ◽  
Y. Magara

Physical characteristics of flocs formed by new polymeric inorganic coagulant, polysilicato-iron coagulant (PSI) were investigated using kaolinite clay suspended water as test water. Floc density was determined by measuring floc settling velocity and spherical equivalent floc diameter. The floc density function proposed by Tambo and Watanabe could be applied to PSI. Flocs formed by PSI showed higher floc density than those formed by alum at the same floc size. Floc size distribution after the rapid mixing as also determined. PSI could produce well-grown flocs at the stirring speed of 300 rpm. Stirring at 300 rpm for 7 minutes, residual turbidity after 15 minute sedimentation became lower than rapid mixing at 120 rpm for 5 minutes followed by slow mixing at 40 rpm for 25 minutes. Flocs formed by PSI was much stronger than those formed by alum. Using the data obtained, the design parameters of flocculator by use of PSI were estimated following Tambo and WatanabeÕs procedure. According to the estimation, it was suggested that rapid mixing process alone can make well-grown flocs and slow mixing process, which is essential for the conventional water purification system using aluminium coagulants, can be eliminated by use of PSI.

2017 ◽  
Vol 24 (14) ◽  
pp. 3206-3218
Author(s):  
Yohei Kushida ◽  
Hiroaki Umehara ◽  
Susumu Hara ◽  
Keisuke Yamada

Momentum exchange impact dampers (MEIDs) were proposed to control the shock responses of mechanical structures. They were applied to reduce floor shock vibrations and control lunar/planetary exploration spacecraft landings. MEIDs are required to control an object’s velocity and displacement, especially for applications involving spacecraft landing. Previous studies verified numerous MEID performances through various types of simulations and experiments. However, previous studies discussing the optimal design methodology for MEIDs are limited. This study explicitly derived the optimal design parameters of MEIDs, which control the controlled object’s displacement and velocity to zero in one-dimensional motion. In addition, the study derived sub-optimal design parameters to control the controlled object’s velocity within a reasonable approximation to derive a practical design methodology for MEIDs. The derived sub-optimal design methodology could also be applied to MEIDs in two-dimensional motion. Furthermore, simulations conducted in the study verified the performances of MEIDs with optimal/sub-optimal design parameters.


2021 ◽  
Vol 43 ◽  
pp. 102203
Author(s):  
Paulo Marcos Faria Maciel ◽  
Natália de Melo Nasser Fava ◽  
Antônio Wagner Lamon ◽  
Pilar Fernandez-Ibañez ◽  
John Anthony Byrne ◽  
...  

Author(s):  
Ю.А. Ремизова ◽  
А.П. Голованова ◽  
Д.А. Рудакова ◽  
А.Г. Митилинеос

Для удаления остаточных количеств фармацевтических соединений, присутствующих в питьевой воде, на всех этапах водоподготовки могут применяться разнообразные способы очистки, основанные на различных физико-химических принципах. В работе приведены результаты экспериментального исследования эффективности удаления с помощью бытовой стационарной системы водоочистки остаточных количеств фармацевтических препаратов – антибиотика левомицетина (хлорамфеникола) и стероидного гормона эстрона – из модельного раствора, приготовленного на основе водопроводной воды с добавлением лекарственных препаратов. Показано, что бытовая система водоочистки обладает способностью существенно снижать остаточные концентрации фармацевтических препаратов левомицетина и эстрона на всем протяжении заявленного производителем ресурса. В секторе бытовой водоочистки установки адсорбционного типа по-прежнему остаются наиболее востребованным типом водоочистных систем, обеспечивающих высокую эффективность удаления различных загрязнителей при минимальных капитальных затратах. To remove residual amounts of pharmaceutical compounds present in drinking water, a variety of purification methods based on various physicochemical principles can be used at all stages of water treatment. The paper presents the results of an experimental study of the efficiency of removing residual concentrations of pharmaceuticals – laevomycetin antibiotic (chloramphenicol) and estrone steroid hormone – from a model solution prepared on the basis of tap water with the addition of drugs, using a home fixed water purification system. It is shown that the home water purification system provides for the significant reduction of residual concentrations of chloramphenicol and estrone throughout the service life declared by the manufacturer. In the household water purification sector, adsorption-type units are still the most in-demand type of water purification systems that provide for the high efficiency in removing various pollutants with minimal capital costs.


2011 ◽  
Vol 31 (16) ◽  
pp. 3354-3357 ◽  
Author(s):  
Lorena Aires Lombardi Queiroz ◽  
Mariana de Oliveira Carvalho ◽  
João Borges Laurindo ◽  
Vivaldo Silveira Júnior

1994 ◽  
Vol 20 (3) ◽  
pp. 360-366
Author(s):  
Yasuo Koseki ◽  
Nobuko Hashimoto ◽  
Kazuhiko Takino ◽  
Toshihiko Kaneko ◽  
Syunji Honma

2016 ◽  
Vol 4 (1) ◽  
Author(s):  
Shavin Pinto ◽  
Yung Wong ◽  
Kyle Fennesy ◽  
Yan Tang ◽  
Mark Compare

This paper presents the design and commissioning of a solar powered water purification system at the Ryan Epps Home for Children (REHC) in Michaud, Haiti. This systemsupplies clean drinking water to the 200 children who live and go to school at REHC and also tothe community in the form of a micro-business. This micro-business is the mechanism for incomegeneration for sustainable system operation. The purifier uses a three stage filtration system witha disc-type sediment filter, a 0.1 micron ultrafiltration membrane, and an ultraviolet light fordisinfection. The backwash cycle extends the life of the ultrafiltration membrane to 4 – 7 yearsbefore a new filter is required. Simplicity in operation was an important design considerationbecause it facilitates local operator training, and understanding. To further ensure completeunderstanding of operation, a pictorial quick-start manual was developed so that operators onlyneed to follow the diagrams laid out on the manual. The design folder with CAD drawings,schematics, datasheets, and troubleshooting guide are left with the local operators. Testingbefore shipping and after installation to ensure proper operation upon installation and on-sitewater quality testing ensures it will promote improved community health.


2020 ◽  
Author(s):  
Bradley Rogers ◽  
Mark Henderson ◽  
Thomas Sugar ◽  
Chell Roberts

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