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41.
A novel reactor concept has been developed that combines Ca2+ removal and BOD conversion under mesophilic (30 °C ) as well as under thermophilic (55 °C ) conditions. Soluble Ca2+, present in many industrial wastewaters, precipitates as a result of forced aeration in the aerobic bioreactor. The CaCO3 precipitates, in turn, act as a carrier material for biofilm growth. This resulted in dense rapidly settling sludge granules covered with a biofilm on the surface. These sludge characteristics facilitate the application of hydraulic retention times of 1 h while maintaining a high biological activity in the reactor. 相似文献
42.
Two kinds of biocarriers were adopted and a combined process of “AMC (Anaerobic microorganism carrier)-UASB and PBG (Porous bio-gel)-MBBR” was operated at the pilot scale for the treatment of real textile wastewater. The influence mechanism of the two carriers on the start-up, pollutant removal and sludge reduction were investigated within 118 days of operation. The dominant functional bacteria in anaerobic and aerobic systems were identified by high-throughput sequencing, and the possible ways and related mechanisms of nutrient removal and sludge reduction were analyzed based on the data. 37.0 ± 7.5 % and 53 ± 12.7 % of COD removal efficiencies were achieved in anaerobic system and aerobic system, respectively. Ammonia nitrogen concentration decreased from 20 to 45 to 3.49 ± 0.54 mg/L after treatment. An anaerobe was found to be closely related to color removal, which existed in both anaerobic and aerobic systems, achieving 84.0 % of color removal. With the operation of the system, the sludge yield decreased gradually. The sludge yields of anaerobic and aerobic systems were calculated individually and compared with similar studies. Aging biofilms were characterized to explore the factors associated with biofilm renewal. 相似文献
43.
《Biocatalysis and Biotransformation》2013,31(2):255-259
AbstractHydrogen peroxide was produced from bran by a two-step process using cellulase/xylanase and glucose oxidase, sequentially. The decolourization efficiency of the produced reagent was tested using paprika oil dye (effluent from industrial source) and high levels of colour removal (96%) were achieved after saponification pre-treatment and hydrogen peroxide application. The method is economically and environmentally advantageous since lower energy and chemical input are needed and wastewater pollution is considerably reduced. At the same time, the utilization of waste materials was successfully achieved. 相似文献
44.
A biofilter composed of yeasts and cassava peel was used to detoxify fertilizer plant effluent. The biological oxygen demand was reduced on treatment from a range of 1200–1400 mg/l to a range 135–404 mg/l. The ammonia-nitrogen (NH3–N) and nitrate-nitrogen (NO3–N) were reduced after treatment from 1000 to 10 mg/l and from 100 to 17.6 mg/l, respectively. The biofilter is simple and easy to handle with high efficiency of 98%. 相似文献
45.
Bakshi Dapinder K. Gupta K.G. Sharma Prince 《World journal of microbiology & biotechnology》1999,15(4):507-509
Biodecolorization of a synthetic commercial textile dye effluent (0.1 gl–1) by Phanerochaete chrysosporium was enhanced by improving the original Kirk's medium with respect to buffer, C:N ratio, Mg2+ and Zn2+ ions, inoculum, temperature shifts, agitation and sunflower oil additon. An increase of 6.7-fold in lignin peroxidase (LIP) level, 4-fold in biomass and 45.5% enhanced decolorization of effluent was achieved. Degradation was both enzymatic (47.2%) and by biosorption (61.67%). 相似文献
46.
47.
Dyes have been synthesised1, which make it possible to prestain proteins prior to electrophoresis on polyacrylamide gels. After discussing the criteria which have to be fulfilled by the dyes, their method of application is described. The method has been tested on a number of selected acidic and basic proteins and also on peptide obtained by the digestion of bovine serum albumin with cyanogen bromide. Excellent reproducibility, stoichiometry and a sensitivity of 0.2 μg with some proteins has been obtained. 相似文献
48.
Muthu Manikandan Judy Gopal Rangarajulu Senthil Kumaran Vijayaraghavan Kannan Sechul Chun 《Preparative biochemistry & biotechnology》2016,46(2):192-199
Phytoremediation using timber-yielding tree species is considered to be the most efficient method for chromium/tannery effluent-contaminated sites. In this study, we have chosen Albizzia lebbeck, a chromium hyperaccumulator plant, and studied one of its chromium detoxification processes operated by its endophytic bacterial assemblage. Out of the four different groups of endophytic bacteria comprising Pseudomonas, Rhizobium, Bacillus, and Salinicoccus identified from A. lebbeck employed in phytoremediation of tannery effluent-contaminated soil, Bacillus predominated with three species, which exhibited not only remarkable chromium accumulation ability but also high chromium reductase activity. A chromate reductase was purified to homogeneity from the most efficient chromium accumulator, Bacillus sp. DGV 019, and the purified 34.2-kD enzyme was observed to be stable at temperatures from 20°C to 60°C. The enzyme was active over a wide range of pH values (4.0–9.0). Furthermore, the enzyme activity was enhanced with the electron donors NADH, followed by NADPH, not affected by glutathione and ascorbic acid. Cu2+ enhanced the activity of the purified enzyme but was inhibited by Zn2+ and etheylenediamine tetraacetic acid (EDTA). In conclusion, due to its versatile adaptability the chromate reductase can be used for chromium remediation. 相似文献
49.
The aim of the present work was to observe microbial decolorization and biodegradation of the Direct Violet 51 azo dye by
Candida albicans isolated from industrial effluents and study the metabolites formed after degradation. C. albicans was used in the removal of the dye in order to further biosorption and biodegradation at different pH values in aqueous solutions.
A comparative study of biodegradation analysis was carried out using UV–vis and FTIR spectroscopy, which revealed significant
changes in peak positions when compared to the dye spectrum. Theses changes in dye structure appeared after 72 h at pH 2.50;
after 240 h at pH 4.50; and after 280 h at pH 6.50, indicating the different by-products formed during the biodegradation
process. Hence, the yeast C. albicans was able to remove the color substance, demonstrating a potential enzymatic capacity to modify the chemical structure of
pigments found in industrial effluents. 相似文献
50.
Prabhat Kumar Rai 《International journal of phytoremediation》2008,10(5):430-439
The level of heavy metal pollution in Singrauli, an industrial region in India, was assessed and the phytoremediation capacity of a small water fern, Azolla pinnata R.Br (Azollaceae), was observed to purify waters polluted by two heavy metals, i.e., mercury (Hg) and cadmium (Cd) under a microcosm condition. Azolla pinnata is endemic to India and is an abundant and easy-growing free-floating water fern usually found in the rice fields, polluted ponds, and reservoirs of India. The fern was grown in 24 40-L aquariums containing Hg2+ and Cd2+ ions each in concentrations of 0.5, 1.0, and 3.0 mgL?1 during the course of this study. The study revealed an inhibition of Azolla pinnata growth by 27.0–33.9% with the highest in the presence of Hg (II) ions at 0.5 mgL?1 in comparison to the control. After 13 days of the experiment, metal contents in the solution were decreased up to 70–94%. In the tissues of Azolla pinnata, the concentration of selected heavy metals during investigation was recorded between 310 and 740 mgKg?1 dry mass, with the highest level found for Cd (II) treatment at 3.0 mgL?1 containing a metal solution. 相似文献