OBJECTIVE To examine the effect of a new point-of-use treatment for drinking-water, a commercially developed flocculant-disinfectant, on the prevalence of diarrhoea in children. METHODS We conducted a randomized controlled trial among 514 rural Guatemalan households, divided into 42 neighbourhood clusters, for 13 weeks, from 4 November 2002 through 31 January 2003. Clusters assigned to water ...

The processes of coagulation and flocculation using high molecular weight long-chain polymers were applied to treat mine water having fine flocs of which about 93% of the total mass was less than 3.02 microm, representing the size distribution of fine particles. Six different combinations of acryl-type anionic flocculants and polyamine-type cationic coagulants were selected to conduct kinetic t...

To identify the allergy problem of a 36-year old swimming instructor, who experiences heavy itching and rashes whenever she comes in contact with pool water. Patch tests were performed with European standard series and materials from the work floor. A positive patch test to aluminum chloride and flocculant was observed. Occupational dermatitis is, based on a contact allergy to aluminum chloride...

The effect of the degree of polymer branching on retention and drainage performance of flocculated kraft pulp fiber suspensions containing precipitated calcium carbonate (PCC) was investigated and has been correlated with flocs properties obtained by light diffraction scattering (LDS). The results show that polymers of medium charge density are more adequate to be used as retention aids since l...

The importance of various factors relating to the preparation of polyacrylamide flocculant solutions was investigated. For optimum results, these solutions should be agitated for at least 2 hours before use while water of high ionic content should be avoided. The quantity of calcium phosphate precipitated during the clarification reaction and the calcium concentration in clear juice are shown t...

Thickener is a main and fundamental step in modern mining separation processes. In this research, the effectof flocculant consumption rate and feed solid concentration of settling rate of layers was studied with differentconcentrations in iron ore mine of Jalalabad, Zarand, Kerman, Iran. The experiments were performed in two1000 ml graduated cylinders (61 and 62 mm diagonal an...

This study aims at evaluating the impacts of flocculant addition to a submerged membrane bioreactor (SMBR). Three types of common flocculants (FeCl3, PACl and chitosan) were tested based on the performance of organic and nutrients removal, respiration test and fouling control. The data showed that all of the flocculants not only could keep high removal efficiencies of DOC and COD (>90%) compare...

The accumulation of phosphorus (P) and metals is a serious concern with the continuous application of manure to agricultural soils. Solid-liquid separation of swine slurry is a promising approach to reduce P and metal loadings through application of separated liquid (SL) as a nutrient source. However, little information is available on nutrient and metal loadings with the application of SL comp...

Household point-of-use (POU) water treatment technologies targeted at vulnerable populations are microbiologically effective and, in small trials, improve health. We do not understand the factors that influence preference for and adoption of these technologies by target end-users. We cycled 400 rural subsistence farm households in western Kenya through three randomly ordered two-month trials of...