Improvement of Technological Modes of  Electrodialysis Apparatus for Treatment of Chromium-Containing Waste Waters

Retaining of water resources quality is one of the global ecological problems of the modern time. The most promising direction in solving the problem of water resources protection is the reduction of negative environmental influence of waste water from production facilities by upgrading the existing water treatment technologies. To treat utility water, technical and rain water from site facilities of Transneft system entities, the specialists developed and approved standard technological diagrams, which are used in producing treatment facilities. The standard technological diagrams provide for all necessary stages of waste water treatment ensures the reduction of pollution level to normal values. However, during operation of treatment facilities it was established, that to ensure the required quality of waste water treatment with initially high levels of pollution, the new technological solutions are necessary. The author presents the results of scientific-research work, in the context of which the best affordable technologies were identified in the area of the treatment of waste water with increased content of pollutants and non-uniform ingress pattern. On the basis of the research results the technical solutions were developed for optimization of operation of existing waste water treatment facilities by means of using combined treatment of technical and rain waters and utility waste waters and applying bioreactor with movable bed – biochips. The use of bioreactor with movable bed allows the increase in the area of active surface, which facilitates increase and retention of biomass. Biochips are completely immersed into waste waters, and biofilm is formed on the entire volume of immersion area, facilitating retention of biomass and preventing formation of sediments. Due to mixing the floating device with biofilm constantly moves along the whole area of bioreactor, and, in doing so, speeds up biochemical processes and uniformity of treatment. The advantages of a bioreactor with movable bed – its active sludge durability against increased and changing pollutant concentrations, change of waste water temperature and simplicity of application – ensured the possibility of its use for blending utility waters, technical and rain waters.

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Water quality. Determination of the growth inhibition effects of waste waters, natural waters and chemicals on the duckweed Spirodela polyrhiza. Method using a stock culture independent microbiotest

10.3403/30331691 ◽

2017 ◽

Keyword(s):

Water Quality ◽

Growth Inhibition ◽

Natural Waters ◽

Waste Waters ◽

Spirodela Polyrhiza ◽

Stock Culture ◽

Culture Independent

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Maize Stalk as Natural Ion Exchanger for Hazardous Pollutants

Revista de Chimie ◽

10.37358/rc.17.8.5753 ◽

2017 ◽

Vol 68 (8) ◽

pp. 1726-1731

Author(s):

Nicoleta Mirela Marin ◽

Luoana Florentina Pascu ◽

Ioana Stanculescu ◽

Ovidiu Iordache ◽

Denisa Jianu ◽

...

Keyword(s):

Ion Exchange ◽

Kinetic Models ◽

High Selectivity ◽

Ion Exchanger ◽

Exchange Equilibrium ◽

Waste Waters ◽

Cationic Species ◽

Hazardous Pollutants ◽

Tailing Ponds

This paper recommends maize stalk as a cheap natural ion exchanger. Ion exchange equilibrium was studied using thermodynamic and kinetic models. The results showed a high selectivity towards cationic species of antimony (III), molybdenum (VI), lead (II) and arsenium (III). Waste waters and sediments from tailing ponds samples were analysed.

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Coagulation & Ultra-filtration of Laundry Waste Waters using the Shower Water Reuse System (SWRS)

10.21236/ada602659 ◽

2013 ◽

Author(s):

Brian Dempsey

Keyword(s):

Water Reuse ◽

Waste Waters ◽

Ultra Filtration ◽

Reuse System

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Composting of Sewage Sludge of Moscow Waste Water Treatment Plants Using Recycling Filler

Water Practice & Technology ◽

10.2166/wpt.2007.003 ◽

2007 ◽

Vol 2 (1) ◽

Author(s):

D.A. Danilovich ◽

M.N. Kozlov ◽

V.I. Sklyar ◽

Yu.A. Nikolaev ◽

N.M. Shchegolkova ◽

...

Keyword(s):

Waste Water ◽

Water Treatment ◽

Waste Water Treatment ◽

Maximum Temperature ◽

Waste Waters ◽

Organic Additives ◽

Organoleptic Properties ◽

Water Treatment Plants ◽

Waste Water Treatment Plants ◽

The City

This work demonstrates a possibility of composting of municipal waste waters sludge (WWS) digested during 5-7 days, of the Kuryanovo waste water treatment plants (the city of Moscow) without the use of traditional organic additives – sawdust, peat, thatch. As a recycling filler (repeatedly used), enhancing the porosity of the composted mixture, ribbed polyethylene spheres (∅=8 cm) and wood chips (having dimension of 5-10 cm) were used. Composting was performed efficiently in both cases, however, the use of wood ships had technological and economical advantages. The process of composting was carried out during 2-4 weeks and was composed of classical phases of active heating (a rate of 0.2-0.3oC/h was obtained), maintaining of maximum temperature during 1-2 days, and cooling down to the ambient temperature. During the course of composting, a product was obtained, having attractive organoleptic properties, suitable for application in municipal laying-out of greenery.

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Flocculation of Waste Waters from Petroleum Refineries

Water Quality Research Journal ◽

10.2166/wqrj.1974.028 ◽

1974 ◽

Vol 9 (1) ◽

pp. 302-314

Author(s):

André Hade ◽

Acher Elcabetz

Keyword(s):

Electrophoretic Mobility ◽

Light Transmittance ◽

Waste Waters ◽

Critical Coagulation Concentration ◽

Mobility Rate ◽

Anionic Polymers ◽

Petroleum Refineries ◽

Binary Suspension

Abstract Waste waters from petroleum refineries can be considered as a ternary-like system, the components of which have been characterized. They are: the alkaline liquor, the hydrocarbon rich oil in suspension and the silica rich solid also in suspension. The parameters controlling the destabilization and the flocculation of these suspensions have been studied by light transmittance and electrophoretic mobility. Rate of flocculation, critical coagulation concentration (CCC) , critical restabilization concentration and optimum flocculation conditions have been determined for different combinations of added polyelectrolytes and/or simple electrolytes. Among eleven different polyelectrolytes, four of the cationic type were selected for their property to flocculate the suspension. It has been shown that an excess of polyelectrolyte brings about the restabilization of the particules. No flocculation has been observed for any of the anionic polymers tested. Simple electrolytes are found to obey the Schulze-Hardy rule in their flocculation capacity. Various combinations of a polyelectrolyte with a simple salt lead to a lower CCC together with a broader concentration range between destabilization and restabilization. It is concluded that this binary suspension behaved essentially like a classical lyophobic sol.

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Stabilization of Hazardous Materials into Ferrites

Water Science & Technology ◽

10.2166/wst.1991.0438 ◽

1991 ◽

Vol 23 (1-3) ◽

pp. 399-404 ◽

Cited By ~ 12

Author(s):

Y. Tamaura ◽

P. Q. Tu ◽

S. Rojarayanont ◽

H. Abe

Keyword(s):

Aqueous Solution ◽

Heavy Metal ◽

Metal Ions ◽

Present Method ◽

Hazardous Materials ◽

Precipitation Process ◽

Waste Waters ◽

Formation Reaction ◽

Coating Method ◽

Hazardous Metal

Stabilization of the hazardous materials by the Fe3O4-coating method was studied. In the ferrite-formation reaction in the aqueous solution, the adsorption of the metal ions and the oxidation of the adsorbed Fe(II) ions are repeated on the surface of the ferrite particles. This reaction was adopted to the coating of the hazardous materials with the Fe3O4(or ferrite). By repeating the two steps of l)the addition of the Fe(II) aqueous solution into the suspension of the hazardous materials, and 2)the oxidation by passing air through the reaction suspension, with the Fe3O4 layer, we could coat the surfaces of the hazardous materials, such as the heavy metal sludge from the neutralization-precipitation process, the CaF2 precipitates in the treatment of the waste waters containing fluoride ion along with hazardous metal ions, and the soils containing Cd(II) ion. These Fe3O4-coated hazardous materials are very stable and no heavy metal ions are leached under the normal environmental conditions. The ferrite sludges formed in the “Ferrite Process” were highly stabilized by the present method, and by the heat-treatment.

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Cake Formation in Cross-Flow Microfiltration Systems

Water Science & Technology ◽

10.2166/wst.1992.0244 ◽

1992 ◽

Vol 25 (10) ◽

pp. 149-162 ◽

Cited By ~ 20

Author(s):

V. L. Pillay ◽

C. A. Buckley

Keyword(s):

Cross Flow ◽

Operating Conditions ◽

Waste Waters ◽

Domestic Waste ◽

Time Curve ◽

Good Correspondence ◽

Operating Variables ◽

Start Up ◽

Turbulent Flow Regime ◽

Cake Formation

Cross-flow microfiltration (CFMF) has potentially wide application in the processing of industrial and domestic waste waters. Optimum design and operation of CFMF systems necessitates a knowledge of the characteristic system behaviour, and an understanding of the mechanisms governing this behaviour. This paper is a contribution towards the elucidation and understanding of the behaviour of a woven fibre CFMF operated in the turbulent flow regime. The characteristic flux-time curve and effects of operating variables on flux are presented for a limestone suspension cross-flow filtered in a 25 mm woven fibre tube. The phenomena contributing to the shape of the flux-time curve are discussed. A model of the mechanisms governing cake growth and limit is presented. Predicted steady-state fluxes show a notably good correspondence with experimentally measured values. It is also found that the flux may not be uniquely defined by the operating conditions, but may also be a function of the operating path taken to reach the operating point. This is of significance in the start-up and operation of CFMF units.

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Discharge of Stable Organic Substances from the Chemical Industries

Water Science & Technology ◽

10.2166/wst.1994.0474 ◽

1994 ◽

Vol 29 (9) ◽

pp. 179-185 ◽

Cited By ~ 1

Author(s):

Åke Undén

Keyword(s):

Waste Water ◽

Organic Substances ◽

Waste Waters ◽

Major Chemical

In a programme started in 1988, the waste water discharges from the major chemical industries in Sweden have been investigated. The primary objectives were to gather information on the major sources of such discharges and to initiate action so as to achieve significant reductions where required. In this paper the investigation programme is presented together with some early conclusions. As could be expected there are no simple common rules for these industries, each effluent should be considered as a separate problem. It was concluded that these waste waters were in most cases more toxic than was acceptable, and that further purifying measures were required in these cases.

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