Synthesis, microscopy and manipulation of colloidal matter

Many cities need to build compact wastewater treatment plants because of lack of land. This paper discusses compact treatment methods. An enhanced primary treatment process based on coarse media filtration is analysed. A high-rate secondary wastewater treatment process has specifically been investigated, consisting of a highly loaded moving bed biofilm reactor directly followed by a coagulation and floc separation step. The objective with this high-rate process is to meet secondary treatment effluent standards at a minimum use of chemicals, minimum sludge production and minimum footprint. It is demonstrated that the biofilm in the bioreactor mainly deals with the soluble organic matter while coagulation deals with the colloidal matter. The bioreactor may, therefore, be designed based on the soluble COD loading only, resulting in a very compact plant when a compact biomass/floc separation reactor (i.e. flotation or direct filtration) is used. The paper reports specifically on the coagulant choice in flotation and filter run time in direct filtration.

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CHEMICAL AND MICROBIOLOGICAL FACTORS IN SOME QUEBEC SOILS

Canadian Journal of Research ◽

10.1139/cjr32-083 ◽

1932 ◽

Vol 7 (3) ◽

pp. 300-327 ◽

Cited By ~ 4

Author(s):

R. R. McKibbin ◽

P. H. H. Gray

Keyword(s):

Organic Matter ◽

Field Data ◽

Large Area ◽

Sandy Clay ◽

Orchard Soil ◽

Heavy Clay ◽

Colloidal Matter ◽

Soil Groups

The major soil groups in a large area of agricultural Quebec have been defined and the primary factors effecting differentiation studied. Organic-matter relations as well as the variations in mineral colloidal matter have determined the groupings adopted. Eight major soil groups are named; viz., heavy clay, sandy clay, lowland podsol, upland podsol, brown earth, orchard soil, lowland muck swamp and upland muck swamp. Chemical and microbiological studies of representative virgin soils within each of the first-named six groups are reported, and field data presented.

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A Study of Suspended and Colloidal Matter in the Leachate from Lysimeters and its Role in Pesticide Transport

Journal of Environmental Quality ◽

10.2134/jeq1999.00472425002800020025x ◽

1999 ◽

Vol 28 (2) ◽

pp. 595-604 ◽

Cited By ~ 45

Author(s):

F. Worrall ◽

A. Parker ◽

J. E. Rae ◽

A. C. Johnson

Keyword(s):

Pesticide Transport ◽

Colloidal Matter

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Interactions of emerging contaminants with model colloidal microplastics, C60 fullerene, and natural organic matter – effect of surface functional group and adsorbate properties

Environmental Science Processes & Impacts ◽

10.1039/d0em00026d ◽

2020 ◽

Vol 22 (5) ◽

pp. 1190-1200

Author(s):

Tyler Williams ◽

Clare Walsh ◽

Keith Murray ◽

Mahamud Subir

Keyword(s):

Organic Matter ◽

Particulate Matter ◽

Natural Organic Matter ◽

Emerging Contaminants ◽

Functional Group ◽

C60 Fullerene ◽

Surface Functional Group ◽

Colloidal Matter ◽

Matter Effect ◽

Effect Of Surface

Molecular properties of emerging contaminants (ECs) and interfacial compositions of colloidal matter dictate the extent of EC–particulate matter surface interaction.

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Direct Observation of Deformation in Microgel Filtration

Scientific Reports ◽

10.1038/s41598-019-55516-w ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 7

Author(s):

John Linkhorst ◽

Jonas Rabe ◽

Lukas T. Hirschwald ◽

Alexander J. C. Kuehne ◽

Matthias Wessling

Keyword(s):

Soft Matter ◽

Filter Cake ◽

Productivity Loss ◽

Microfluidic Channel ◽

Transmembrane Flux ◽

Colloidal Matter ◽

Realistic Description ◽

On Line ◽

The Individual ◽

Crystalline Domains

AbstractColloidal filtration processes using porous membranes suffer from productivity loss due to colloidal matter retention and continuous build-up by the retained matter. Especially during filtration of soft matter, the deformation of the individual colloids that make up the filter cake may be significant; however, this deformation and its impact remain unresolved so far. Yet, understanding the deformation on the single colloid level as well as on the ensemble level is important to be able to deconvolute filter cake properties from resistance increase of the membrane either by simultaneous internal adsorption or blocking of pores. Here, we report on the compression of a filter cake by filtrating soft microgels in a microfluidic channel in front of a model membrane. To study the single colloid deformation amorphous and crystalline domains were built up in front of the membrane and visualized on-line using confocal fluorescence microscopy while adjusting the degree of permeation, i.e., the transmembrane flux. Results show locally pronounced asymmetric deformation in amorphous domains, while the microgels in colloidal crystals approached regular polyeder shape. Increasing the flux beyond the maximum colloid deformation results in non-isochoric microgel behavior. The presented methodology enables a realistic description of complex colloidal matter deposits during filtration.

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