scholarly journals Předčištění odpadních vod z produkce vína

Entecho ◽  
2020 ◽  
Vol 3 (1) ◽  
pp. 10-16
Author(s):  
Nikola Musilová ◽  
Martin Pečenka
Keyword(s):  
Biological Treatment ◽  
Cod Removal ◽  
Ph Adjustment ◽  
Term Operation ◽  
Winery Wastewater ◽  
Laboratory Conditions

Práce se zabývá porovnáním procesů předčištění odpadních vod z výroby vína za laboratorních podmínek. Tyto vody jsou charakteristické nízkým pH a vysokým obsahem organických a nerozpuštěných látek. Nadlimitní hodnoty parametrů CHSKCr a BSK5 jsou často v rozporu s příslušným kanalizačním řádem, což komplikuje jejich odvádění a čištění na biologických čistírnách odpadních vod. Z fyzikálně chemických metod předčištění byla testována koagulace v kombinaci s flokulací. Zároveň byly provozovány dva vsádkové reaktory za rozdílných provozních podmínek. Cílem práce bylo nalezení efektivního a ekonomicky únosného postupu pro snížení hodnot CHSKCr a BSK5 za účelem přiblížení se limitům daných kanalizačním řádem. Abstract (en) COD removal from winery wastewater by physicochemical and biological treatment at lab scale was studied. Both experiments were performed with sludge from clarification under laboratory conditions. The aim of those experiments was to meet regulations. Coagulation under different pH was studied. By combination of coagulant Yesfloc (c) SG and flocculant Yesfloc® COE65 or flocculant Yesfloc® COEX88 28 % of COD was removed by pH = 6 and 27 % of COD was removed by pH = 8. Two SBR reactors under different conditions were studied. Average of COD removal with both SBR was 77 %, which met regulations. There was no significant lack of nutrients, which could occur in a long-term operation. The pH adjustment for SBR was not necessary. The composition and season dependency could be a problem for biological treatment, but the sludge adaptation was really quick.

Analysis of crystallite size changes in a hematite and magnetite formed on steel used in the power idustry

2017 ◽  
Vol 1 (21) ◽  
pp. 65-73
Author(s):  
Monika Gwoździk
Keyword(s):  
Elevated Temperature ◽  
Oxide Layer ◽  
Cross Section ◽  
X Ray ◽  
Term Operation ◽  
Diffraction Line Profile ◽  
Crystallite Sizes ◽  
Scherrer Formula ◽  
Pipe Outlet

The paper presents results of studies on the crystallite sizes of oxide layer formed during a long-term operation on 10CrMo9-10 steel at an elevated temperature (T = 545° C, t = 200,000 h). This value was determined by a method based on analysis of the diffraction line profile, according to a Scherrer formula. The oxide layer was studied on a surface and a cross-section at the outer and inner site on the pipe outlet, at the fire and counter-fire wall of the tube. X-ray studies were carried out on the surface of a tube, then the layer’s surface was polished and the diffraction measurements repeated to reveal differences in the originated oxides layer.

Characterization and treatability studies of cigarette industry wastewaters: a case study

1997 ◽  
Vol 36 (2-3) ◽  
pp. 69-74
Author(s):  
G. Bozarslan ◽  
S. K. Çelebi ◽  
F. Sengül
Keyword(s):  
Chemical Treatment ◽  
Biological Treatment ◽  
Continuous System ◽  
Cod Removal ◽  
Optimum Dose ◽  
Fenton Reagent ◽  
Cigarette Industry ◽  
Settling Behaviour ◽  
Characterization Studies

In this study, the wastewater of one of the cigarette factories in Izmir was characterized and treatability studies were done. The characterization studies of the wastewater showed that the COD, and the pH changes drastically. The chemical treatability studies of the influent wastewater were done by using Ca(OH)2, FeCl3 and Fenton Reagent. The optimum dose of FeCI3 was determined by jar tests. When using Ca(OH)2, the best flocculation, settling behaviour, and the highest COD removal occurred around pH 11. The optimum doses of Fenton Reagent (FeSO4 and H2O2) were determined. The supernatants of the previously chemically treated wastewaters were used for biological treatment. According to total COD removal efficiencies and the amount of sludge production during chemical treatment, FeCl3 was found to be the most economical and effective coagulant. Chemical treatment units were designed for a batch and a continuous system. The batch system has more advantages than a continuous system in this case.

Retention and expression of recombinant plasmids in suspended and biofilm-bound bacteria degrading trichloroethene (TCE)

1997 ◽  
Vol 36 (10) ◽  
pp. 1-8 ◽  
Author(s):  
James D. Bryers ◽  
Robert R. Sharp
Keyword(s):  
Biofilm Reactor ◽  
Bacterial Biofilm ◽  
Laboratory Evaluation ◽  
Recombinant Bacteria ◽  
Suitable Host ◽  
Term Operation ◽  
Open Environment ◽  
Recombinant Microorganisms ◽  
Extracellular Polymer

Exposure of plasmid recombinant microorganisms to an open environment, either inadvertently or intentionally, requires research into those fundamental processes that govern plasmid retention, transfer and expression. In the open environment, a majority of the microbial activity occurs associated with an interface, within thin biological layers consisting of cells and their insoluble extracellular polymer, layers known as biofilms. Current toxic wastewater or wastegas treatment reactors exploit bacterial biofilm systems for certain system operating advantages. Using recombinant bacteria within a biofilm reactor to degrade xenobiotic wastes requires finding a suitable host to harbor and express the desired plasmid phenotype. Suitable host characteristics include: the ability to produce copious amounts of biofilm, resistance to waste-related injury and toxicity, and the ability to retain and express the desired plasmid during long term operation. This paper reports on a laboratory evaluation of factors governing plasmid retention and the expression of trichloroethene (TCE) degradative capacity in both suspended and biofilm cultures.

Restoration of cylinder liners for automotive tractors engines in modern conditions

2020 ◽  
pp. 122-133
Author(s):  
Vyacheslav A. Denisov ◽  
Aleksandr Yu. Kostyukov ◽  
Roman N. Zadorozhniy
Keyword(s):  
Adhesion Strength ◽  
Electrode Materials ◽  
Research Purpose ◽  
Laboratory Studies ◽  
Term Operation ◽  
Operational Load ◽  
Operational Tests ◽  
Conducting Research ◽  
Cylinder Liners

One of the most promising technologies for restoring machine parts and cylinder liners is electric spark treatment as the most versatile technology that provides high-quality restoration of worn parts with wear up to 0.5 mm. (Research purpose) The research purpose is in developing a technology for restoring various cylinder liners by means of electric spark processing, selecting optimal modes and electrode materials that allow improving the quality of repair and increasing the post-repair life of the sleeve. (Materials and methods) It was taken into account when conducting research aimed at restoring the geometric parameters of the sleeve, that the coating must have sufficient adhesion strength to the surface of the sleeve under mechanical, thermal loads and long-term operation. Laboratory studies of the adhesion strength of electric spark coatings on the separation (adhesive) and on the cut, as well as tribotechnical studies of interfaces were conducted. Authors have found by analyzing the results of operational tests of restored and new cylinder liners the prospects for using electric spark treatment of worn parts, including diesel engine liners. (Results and discussion) It was shown by laboratory studies of the adhesion strength of electric spark coatings with a 0.2 mm thick BrMKc 3-1 electrode to the working surface of cylinder liners that their separation strength (adhesive) was 20-40 megapascals, and the shear strength (cohesive) was 50-80 megapascals. It was found that this provides the required functional strength of coatings with maximum operational load. The article presents the results of comprehensive research in graphs and tables. (Conclusions) The research conducted in the CCP "Nano-Center" of the FSAC VIM and operational tests in the 2nd bus fleet of Moscow confirmed the principal possibility of effectively restoring cast iron liners (blocks) using the technology of electric spark processing.

Structure and properties of rails after extremely long-term operation

2020 ◽  
pp. 30-39 ◽  
Author(s):  
Yu. F. Ivanov ◽  
V. E. Gromov ◽  
V. E. Kormyshev ◽  
A. M. Glezer
Keyword(s):  
Surface Layer ◽  
Lattice Parameter ◽  
Crystal Lattice Parameter ◽  
Subgrain Structure ◽  
Structure And Properties ◽  
Term Operation ◽  
Head Section ◽  
Structure Phase ◽  
Defective Surface

The paper reveals regularities and mechanisms of structure-phase states and properties formation of of differentially hardened 100-m rails of DT 350 category after the passed tonnage of 1411 mln. tons brutto. The formation of highly defective surface layer with nanosize (40–50 nm) grain-subgrain structure of pearlite colonies and submicrocrystal (150–250 nm) structure grains with structure free ferrite is detected. The change of hardness, microhardness, crystal lattice parameter, microdistorsion level, scalar and excess dislocation density on the rails head section are analyzed. The possible mechanisms of cementite plates’ transformation at extremely long-term operation are discussed.

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