Integrated LC resonant converter and silent discharge ozonizer for colour removal

The research object is the electromagnetic processes in the semiconductor power converters based on the schemes with circuit commutation and containing resonant circuits of reactive elements and transformers with a small coupling coefficient. The research aim is to develop a technology for a fast wireless battery charging for the use in clean energy vehicles, which would be based on a resonant converter with a pulse-count adjustment with a phase shift control. The latter provides a high energy performance in a wide range of regulation and a low sensitivity to changes in the magnetic system parameters. This is a final report. The report presents the results of the work performed in accordance with the Terms of Reference for the second stage of the scientific and research work. The following theoretical problems have been solved: development of a mathematical model of a series resonant converter with a pulse-count adjustment for contactless inductive energy transmission, which provided a high accuracy for the studies of the electromagnetic processes in the power section of multi-circuit resonant converters for contactless energy transmission, as well as an opportunity to assess the energy parameters of multi-circuit converters at pulse-count adjustment; compilation of mathematical dependencies of the average input and output current values on the number of half-cycles of resonant oscillations during energy transmission to the circuit and energy dissipation, the supply voltage and the resonant circuit’s parameters, which allowed assessing the converter’s energy parameters over a wide control range; compilation of the dependencies of the converter’s output power and coefficient of efficiency on the number of halfcycles of resonant oscillations during energy transmission to the circuit and energy dissipation, on supply voltage and on the resonant circuit’s parameters, which made it possible to evaluate the efficiency of the pulse-count adjustment of resonant converters for contactless energy transmission; realization of a dynamic model of a resonant converter for contactless energy transmission in the form of transfer functions for small disturbances caused by fluctuations in supply voltage, which made it possible to estimate the effect of its instability on the quality of output current stabilization.

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Extra colour removal in a refinery

Sugar Industry ◽

10.36961/si12200 ◽

2011 ◽

pp. 718-725 ◽

Cited By ~ 1

Author(s):

Laura Diego ◽

Fernando Martín ◽

Marta G de Quevedo ◽

Jaime Sagristá

Keyword(s):

Refining Process ◽

Ion Exchange Resins ◽

Colour Removal ◽

Precipitated Calcium Carbonate ◽

Sodium Bisulphite ◽

Powdered Carbon ◽

Raw Sugar ◽

Sugar Refinery ◽

Exchange Resins ◽

Main Factor

The main factor affecting the raw sugar refining process is certainly “colour”. The higher colour removal, the higher is the obtained sugar yield. Therefore, colour removal is the main goal throughout the process. In a conventional sugar refinery colour is removed in the purification and decolorisation steps – the second one is normally done using ion-exchange resins – but there are some other ways of colour removal such as adding some colour removing agents (powdered carbon, sodium bisulphite, PCC [precipitated calcium carbonate]). In this article the pilot plant results of experiments of increasing colour removal in the refining process are described, such as PCC addition, 3rd carbonatation (re-purification), hydrogen peroxide addition, powdered carbon addition, sodium bisulphite addition and crystallization improvements. The good results achieved in some of these trials led to perform some industrial trials, the results of wich are summarized in this article as well.

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Decolorisation of natural organic matter by Phanerochaete chrysosporium: the effect of environmental conditions

Water Science & Technology Water Supply ◽

10.2166/ws.2004.0075 ◽

2004 ◽

Vol 4 (4) ◽

pp. 175-182 ◽

Cited By ~ 2

Author(s):

K. Rojek ◽

F.A. Roddick ◽

A. Parkinson

Keyword(s):

Organic Matter ◽

Ionic Strength ◽

Natural Organic Matter ◽

Phanerochaete Chrysosporium ◽

Fungal Growth ◽

Low Ph ◽

Colour Removal ◽

Humic Material ◽

Carbon And Nitrogen ◽

Carbon And Nitrogen Content

Phanerochaete chrysosporium was shown to rapidly decolorise a solution of natural organic matter (NOM). The effect of various parameters such as carbon and nitrogen content, pH, ionic strength, NOM concentration and addition of Mn2+ on the colour removal process was investigated. The rapid decolorisation was related to fungal growth and biosorption rather than biodegradation as neither carbon nor nitrogen limitation, nor Mn2+ addition, triggered the decolorisation process. Low pH (pH 3) and increased ionic strength (up to 50 g L‒1 added NaCl) led to greater specific removal (NOM/unit biomass), probably due to increased electrostatic bonding between the humic material and the biomass. Adsorption of NOM with viable and inactivated (autoclaved or by sodium azide) fungal pellets occurred within 24 hours and the colour removal depended on the viability, method of inactivation and pH. Colour removal by viable pellets was higher under the same conditions, and this, combined with desorption data, confirmed that fungal metabolic activity was important in the decolorisation process. Overall, removals of up to 40–50% NOM from solution were obtained. Of this, removal by adsorption was estimated as 60–70%, half of which was physicochemical, the other half metabolically-dependent biosorption and bioaccumulation. The remainder was considered to be removed by biodegradation, although some of this may be ascribed to bioaccumulation and metabolically-dependent biosorption.

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Use of a sequencing batch biofilter for degradation of azo dyes (acids and bases)

Water Science & Technology ◽

10.2166/wst.2000.0532 ◽

2000 ◽

Vol 42 (5-6) ◽

pp. 329-336 ◽

Cited By ~ 8

Author(s):

M. Quezada ◽

I. Linares ◽

G. Buitrón

Keyword(s):

Azo Dyes ◽

Azo Dye ◽

Degradation Rate ◽

Removal Rate ◽

Textile Effluent ◽

Colour Removal ◽

Substrate Degradation ◽

Acids And Bases ◽

Removal Efficiencies ◽

Basic Red 46

The degradation of azo dyes in an aerobic biofilter operated in an SBR system was studied. The azo dyes studied were Acid Red 151 and a textile effluent containing basic dyes (Basic Blue 41, Basic Red 46 and 16 and Basic Yellow 28 and 19). In the case of Acid Red 151 a maximal substrate degradation rate of 288 mg AR 151/lliquid·d was obtained and degradation efficiencies were between 60 and 99%. Mineralization studies showed that 73% (as carbon) of the initial azo dye was transformed to CO2 by the consortia. The textile effluent was efficiently biodegraded by the reactor. A maximal removal rate of 2.3 kg COD/lliquid·d was obtained with removal efficiencies (as COD) varying from 76 to 97%. In all the cycles the system presented 80% of colour removal.

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