首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 22 毫秒
1.
The present study reports on the treatment of pulp and paper mill effluent by Phanerochaete chlysosporium and the same has been compared at two different pH, 5.5 and 8.5. At both the pH, colour, COD, lignin content and total phenols of the effluent significantly declined after bioremediation. However, greater decolourisation and reduction in COD, lignin content and total phenols were observed at pH 5.5. Such bioremediated effluent of pulp and paper mill could gainfully be utilized for crop irrigation.  相似文献   

2.
The effect of pH, nutrient and aeration was studied on the removal of colour and reduction of BOD, COD and heavy metals with addition of readily available source of nitrogen and phosphorus in concentration of 1.0 g/L. Recalcitrant compound was effectively degraded by active microbial consortia. The isolated bacteria were identified as Pseudomonas putida (S1), Citrobacter sp. (S4) and Enterobacter sp. (S5). These organisms not only decolourised effluent upto 97% but reduced BOD, COD, phenolics and sulfide upto 96.63, 96.80, 96.92 and 96.67% respectively within 24 hrs of aeration and the heavy metals were removed upto 82-99.80%. The TSS and TDS were sharply reduced due to degradation. The absorption maxima was also decreased to 90%. However, in control without the microbial consortium no noticeable change was produced.  相似文献   

3.
Calcium carbonate is used in large amounts in the pulp and paper industry as a paper filler. When it is manufactured, the calcium carbonate waste is purged from the process. Here we demonstrate that, due to the elevated calcium concentration of 168.5 g kg−1 dry weight (dw), alkaline pH of 12.6 and neutralizing (liming) effect value of 42.4% expressed as Ca equivalents, this waste is a potential liming agent and a pH buffer. The heavy metal concentrations in the waste were lower than the new Finnish limit values for fertilizers used in agriculture, as well as for a material, e.g. ash, used as an earth construction agent. These limit values came into force in March 2007 and in June 2006, respectively.  相似文献   

4.
Potential environmental effects of the discharge of industrial wastewater from manufacturing of bleached straw pulp have been studied. Bleached neutral sulphite straw pulping results in discharges of both black cooking and spent bleaching liquors. Time proportional samples were taken from the combined bleaching effluent and the combined mill effluent, (i) Mutagenic activity of the two samples in an Ames’ test, and (ii) acute toxicity of the combined mill effluent sample towards the photosynthetic activity of natural marine phytoplankton from the receiving waters were determined. Also, acute toxicity was determined of the slowly biodegradable or persistent organics remaining after aerobic stabilization of the sample towards (ii) photosynthetic activity of natural phytoplankton, (iii) mussels (Mytilus edulis), (iv) eels (Anguilla anguilla) and, (v) crustacean (Nitocra spinipes); and furthermore, (vi) reproduction test of the crustacean and (vii) growth inhibition test of the marine diatom (Phaeodactylum tricornutum) were performed. Mutagenicity emission factors (MEF's) and toxicity emission factors (TEF's) were calculated to classify the effluents. Combined mill effluent sample showed a mutagenic activity per t90 of one fourth the activity of a kraft pulp bleaching effluent, and the inhibition of the photosynthesis of natural phytoplankton was significant up to 2600 times dilution. After aerobic stabilization, inhibition was observed up to 400 times dilution. Other effects of the combined mill effluent sample were only significant below 40 times dilution. The bleaching effluent showed a mutagenic activity per t90 comparable to kraft bleaching effluents. Other effects were only significant below 20 times dilution.  相似文献   

5.
In the present study sequential anaerobic and aerobic treatment in two step bioreactor was performed for removal of colour in the pulp and paper mill effluent. In anaerobic treatment, colour 50%, lignin 62%, COD 29%, absordable organic halides (AOX) 25% and phenol 29% were reduced in eight days. The anaerobically treated effluent was separately applied in bioreactor in presence of fungal strain, Paecilomyces sp., and bacterial strain, Microbrevis luteum. Data of study indicated reduction in colour 80%, AOX 74%, lignin 81%, COD 93% and phenol 76 per cent by Paecilomyces sp. where as Microbrevis luteum showed removal in colour 59%, lignin 71%, COD 86%, AOX 84% and phenol 88% by day third when 7 days anaerobically treated effluent was further treated by aerobic microorganisms. Change in pH of the effluent and increase in biomass of microorganism's substantiated results of the study, which was concomitant to the treatment method.  相似文献   

6.
Assessment of agropotentiality of the effluent coming out from century pulp and paper mill, Ghanshyamdham, Lalkua (Uttaranchal) has been made on wheat (Triticum aestivum var. UP-2329) crop grown in two soils differing in texture with different effluent concentrations. Diluted effluent increased the chlorophyll content, plant height, shoot and root biomass, grain yield, protein, carbohydrate and lipid contents in wheat grains, while undiluted effluent caused inhibition in plant growth resulting in a sharp decline of yield. Pure soil provided better growth and yield results than those soil mixed with sand.  相似文献   

7.
A screening was carried out in a river receiving pulp mill discharges (BioBio river, central Chile) to study the bacterial population able to tolerate and degrade chlorophenols. In four selected stations and at different seasons, water samples were taken from the river. Total bacterial population and the number of chlorophenol tolerant bacteria were counted. Bacterial tolerance to 25, 50, 100, 200 and 400 μg/ml of 2,4‐dichlorophenol (DCP), 2,4,6‐trichlorophenol (TCP) and pentachlorophenol (PCP) was determined. Strains able to tolerate at least 400 μg/ml chlorophenols were found. Eighteen bacterial strains able to use chlorophenols as the sole carbon source were isolated: five of them were Pseudomonas fluorescens, two Alcaligenes sp., one Citrobacter freundii, one Aeromonas sp. and nine unidentified Gram negative bacilli. A good correlation (r 2 = 0.758) between the logarithm of DCP tolerant bacteria and the content of adsorbable organic halogen (AOX) at low dilution in the river water was established. Four groups of tolerant bacteria were found: growing on PCP and DCP, growing on PCP and TCP, growing only on PCP and growing only on TCP.  相似文献   

8.
A local referendum on a proposed pulp mill in eight New Hampshire towns provides a particularly apt sample for examining preferences on environmental issues. Interviews with 359 voters are examined to test various determinants of voting behavior. A utility maximizing model is tested using multiple-regression logit techniques. Significant variables are respondent's location, income, occupation, and education and the initial environment of the community. There is a brief discussion of public policy issues which these results may illuminate.  相似文献   

9.
Pulp paper mill pollutants are the major source of aquatic contamination having metals, lignin and chlorophenols. Study was conducted to see the effect of these contaminants on antibiotic resistance pattern of isolated bacteria. Pulp paper effluents were evaluated for its physico-chemical properties i.e, BOD 72143 +/- 164.81 to 22.32 +/- 2.48, COD 213136 +/- 583.59 to 60.40 +/- 6.34, total phenol 386 +/- 71.24 to 0.43 +/- 0.0, lignin 26312 +/- 258.59 to 73.67 +/- 31.81and microbial quality i.e. K. pneumonae, S. typhi, S. faecalis, P. aeruginosa, E. coli, Ent. faecalis, A. hydrophila, B. subtilis, S. aureus, Y enterolitica and V vulrificus. Antibiotic sensitivity (10-30 microg), heavy metal resistance (100-1000 microg ml(-1)), lignin (1000-10,000 ppm) and pentachlorophenol (100-1000 ppm) tolerance of bacterial strains were assessed by seven classes of antibiotics. Eleven bacterial isolates were found multidrug resistant towards antibiotics, heavy metal, lignin and PCP. Out of 11 isolates, 90.9% were found resistant against eleven antibiotics which acquired 100% resistant in presence of heavy metal, lignin and chlorophenols. Results also revealed that concentration of lignin (50-350 ppm) and PCP (5-30 ppm) induced maximum growth (273-8050 cfu ml(-1)) of pathogenic bacteria in river water.  相似文献   

10.
The UF membrane fouling by down- and up-flow BAC effluents were compared. Up-flow BAC effluent fouled the membrane faster than down-flow BAC effluent. The combined effects dominated irreversible fouling. The extent of fouling exacerbated by inorganic particles was higher. The TMP, permeate flux, and normalized membrane flux during 21 days of UF of DBAC and UBAC effluents. Fouling during ultrafiltration of down- and up-flow biological activated carbon effluents was investigated to determine the roles of polysaccharides, proteins, and inorganic particles in ultrafiltration membrane fouling. During ultrafiltration of down- flow biological activated carbon effluent, the trans-membrane pressure was≤26 kPa and the permeate flux was steady at 46.7 L?m2?h1. However, during ultrafiltration of up-flow biological activated carbon effluent, the highest trans-membrane pressure was almost 40 kPa and the permeate flux continuously decreased to 30 L?m2?h1. At the end of the filtration period, the normalized membrane fluxes were 0.88 and 0.62 for down- and up-flow biological activated carbon effluents, respectively. The membrane removed the turbidity and polysaccharides content by 47.4% and 30.2% in down- flow biological activated effluent and 82.5% and 22.4% in up-flow biological activated carbon effluent, respectively, but retained few proteins. The retention of polysaccharides was higher on the membrane that filtered the down- flow biological activated effluent compared with that on the membrane that filtered the up-flow biological activated carbon effluent. The polysaccharides on the membranes fouled by up-flow biological activated carbon and down- flow biological activated effluents were spread continuously and clustered, respectively. These demonstrated that the up-flow biological activated carbon effluent fouled the membrane faster. Membrane fouling was associated with a portion of the polysaccharides (not the proteins) and inorganic particles in the feed water. When there was little difference in the polysaccharide concentrations between the feed waters, the fouling extent was exacerbated more by inorganic particles than by polysaccharides.  相似文献   

11.
The effect of Kraft black liquor on the lipid peroxidation of rat homogenates was examined. The lipid peroxidation of homogenates from different organs (kidney, brain, lung, and liver) was induced by Fenton's reagent. The products of lipid peroxidation, lipid hydroperoxides and TBARS were measured by FOX method and TBA assay, respectively. It was found that black liquor significantly reduced the concentration of TBARS, but not the concentration of lipid hydroperoxides. This inhibition was directly proportional to the concentration of Kraft black liquor and the incubation temperature. Conclusively, the black liquor from pulp and paper industry exhibited an antioxidant activity.  相似文献   

12.
The physico-chemical characteristics of paper mill industry effluent were measured and some were found to be above the permissible limits prescribed by Indian irrigation water standard. A study was conducted in pots to investigate the effects of different concentrations (10, 20, 30, 40, 50, 60, 70, 80 and 100%) of paper mill effluent on growth and production of rice, mustard and peafor three years. The study reveals that the paper mill effluent has deleterious effect on the growth of crop at higher concentrations. However, at lower concentration (viz. 10 to 40% in rice, 10 to 50% in mustard and 10 to 60% in pea) of effluent, beneficial impact on general welfare of the crops was noticed. Growth and development was increased with increasing the concentration of the effluent up to 30% in rice, 40% in mustard and 50% in pea. Investigation showed that the growth and production of rice, mustard and pea was found maximum at a concentration of 30, 40 and 50% effluent respectively.  相似文献   

13.
Paper mills have severe problem in disposing effluent or semisolid sludge despite repeated recycling. It requires treatment prior to disposal of sludge. In recent years biological treatment methods received much attention and considered as efficient low-cost treatment. One such method is vermiculture treatment. The present study was carried out to dispose the paper mill sludge biologically using 2 exotic species (Eudrilus eugineae and Eiseniafoetida) and an indigenous species (Lampito mauritii) of earthworm. The paper mill sludge in various concentration 25%,50% and 75% were subjected to vermitub treatment for a period of 60 days. During the period of study data were collected on reproductive strategies of earthworm and chemical analysis of wastes before and after treatment. Results obtained indicate that 25% concentration of sludge was ideal and of the three worms used Eiseniafoetida proved to be the best worm for biomanagement.  相似文献   

14.
Wood charcoal production provides affordable energy in many developing countries and has substantially contributed to the economy through the provision of rural incomes. In several countries, charcoal production leads to overexploitation of forests due to inefficiencies in processing. This study was undertaken in central Laos to (1) examine and document traditional charcoal production systems; (2) investigate the production capacity, recovery efficiencies and economic gains of existing traditional charcoal production methods; (3) characterize the chemical properties of wood charcoal and investigate the potential for soil restoration and (4) investigate local charcoal producers' perception on forest degradation and their species preferences. Through a socio-economic survey, a cost-based method for economic valuation was undertaken on a range of charcoal production methods currently being used. Laboratory chemical analyses were performed on wood charcoal samples. Results indicated that the traditional mud charcoal mound was used by the majority (82%) of charcoal producers. Total charcoal production per production cycle varied between 400 (produced from 2.7 m3 of wood) and 1600 kg (produced from 18 m3 of wood), with a mean of 938 kg (±120) for traditional mud charcoal mounds. The volume of the traditional mud charcoal mounds correlated positively and significantly with total charcoal production (R 2 = 0.45, p?=?0.03), whereas correlated negatively and significantly with the recovery efficiency (R 2 = 0.58, p?=?0.01). On average, the local producers receive a total net benefit of 457,272 Lao kip (USD 57.2) in 17 days. We also identified a rice husk mound method of charcoal production, which may not encourage further deforestation while producing rice husk biochar that can be used for soil restoration. Furthermore, we found that there are significant differences (p < 0.05) between the sampled wood charcoals in chemical properties, indicating that the potential of using wood charcoal for the restoration of degraded soils varies from charcoal to charcoal.  相似文献   

15.
Bioleaching of a low grade chalcopyrite (ball mill spillage material) was tested for copper recovery in shake flasks. The original samples (as received) were thermally activated (600°C, 30 min) to notice the change in physico-chemical and mineralogical characteristics of the host rock and subsequently its effect on copper recovery. A mixed culture of acidophilic chemolithotrophic bacterial consortium predominantly entailing Acidithiobacillus ferrooxidans strain was used for bioleaching studies and optimization of process parameters of both original and thermally activated samples. Mineralogical characterization studies indicated the presence of chalcopyrite, pyrite in the silicate matrix of the granitic rock. Field emission scanning electron microscopy coupled with Energy dispersive spectroscopy (FESEM-EDS) and X-ray Fluorescence (XRF) analysis indicated mostly SiO2. With pH 2, pulp density 10% w/v, inoculum 10% v/v, temperature 30°C, 150 r·min-1, 49% copper could be recovered in 30 days from the finest particle size (-1+ 0.75 mm) of the original spillage sample. Under similar conditions 95% copper could be recovered from the thermally activated sample with the same size fraction in 10 days. The study revealed that thermal activation leads to volume expansion in the rock with the development of cracks, micro and macro pores on its surface, thereby enabling bacterial solution to penetrate more easily into the body, facilitating enhanced copper dissolution.  相似文献   

16.
Environmental Chemistry Letters - Wastewater pollution is a major issue requiring advanced treatment methods such as nanotechnologies. In particular, nanocelluloses appear promising as adsorbents...  相似文献   

17.
Passerine species have been increasingly used as monitors of metal pollution, especially by making use of non-destructive indicators of bird exposure, such as collecting feathers, faeces or blood. During this study, mercury concentrations were determined in feathers, faeces and blood of nestling great tits (Parus major) in industrial (a paper mill) and rural sites on the west coast of Portugal. The aim of this study was to compare the level of mercury in both areas over the study period, as indicated by nestlings’ mercury levels, while assessing possible contamination effects on the breeding performance and health status of great tits. Over the years, feathers showed a significant annual decrease in mercury contamination in the study area. Blood analyses also revealed a significant annual decrease in mercury concentrations, but no significant differences were detected between areas. Faeces data showed no significant difference between years or areas. We found no direct influence of mercury levels on nestling health status or great tit breeding performance.  相似文献   

18.
A series of activated carbons with high surface area were prepared from walnut shell using chemical activation with ZnCl2. In this research the carbonization stage was carried out at 500℃. The performance of the synthesized carbons evaluated in adsorption of benzene and toluene from waste gas. The influence of impregnation ratio on the characteristics of synthesized activated carbons as well as their adsorption capacity was investigated. The ratio of activation agent to walnut shell was selected in the range of 0.5-2.0 wt/wt. The synthesized activated carbons were characterized using XRD, SEM, BET and FTIR techniques. The highest activated carbon production yield was obtained at impregnation ratio of 1.5 wt/wt. The XRD analysis illustrated that peaks intensity decreased with increasing impregnation ratio showing that amorphous property of samples was increased. The SEM analysis revealed successful pore development in synthesized activated carbons obtained at high impregnation ratios. The surface area of the activated carbons increased with increasing impregnation ratio and its maximum value reached 2643 m2.g 1 at impregnation ratio of 2/1. FTIR analysis indicated that the relative amount of different acidic surface groups on synthesized carbons was a function of impregnation ratio. Experimental results for benzene and toluene adsorption showed a high potential of employing synthesized impregnated activated carbon for treatment of waste gas. Generally, the amount of VOC adsorbed on the surface was affected by physicochemical properties of synthesized activated carbons.  相似文献   

19.
Biosorption potential of green macroalgae Cladophora sp., (GAC) for the removal of hexavalent chromium (Cr(VI)) and malachite green (MG) from aqueous medium was investigated. Optimal conditions for biosorption experiments were determined as a function of initial pH, GAC dosage, temperature and initial concentration of Cr(VI) and MG. The biosorption equilibrium data were fitted with the isotherm models of Langmuir, Freundlich, Kiselev, Frumkin and Jovanovic, while the experimental data were analysed using the kinetic models such as pseudo-first-order, pseudo-second-order, Ritchie's and intraparticle diffusion. The Langmuir maximum biosorption capacity was calculated as 100.00?mg/g (Cr(VI)) and 142.85?mg/g (MG). The biosorption kinetic data showed better agreement with the pseudo-second-order kinetic model. The thermodynamic parameters indicated spontaneous and endothermic nature of the biosorption process for Cr(VI) removal, whereas exothermic in the case of MG removal. Furthermore, the biosorption efficiencies of the GAC reusability were found significant up to five cycles and tested using 0.1, 0.5 and 1.0?M HCl, respectively. The results of the present study indicated that GAC is a suitable biosorbent for the sequestration of Cr(VI) and MG from aqueous solutions.  相似文献   

20.
Olive mill waste water (OMWW) originating from a two-phase olive oil-producing plant was treated with a crude peroxidase extract prepared from onion solid by-products. The treatments were based on a 3 × 3 factorial design, employing a series of combinations of pH and H2O2, in order to identify optimal operational conditions. The treatment performance was assessed by estimating the removal percentage of total polyphenols. The model established produced a satisfactory fitting of the data (R 2 = 0.94, p = 0.0158), while the second-order polynomial equation used to describe the process indicated that peroxidase-catalysed polyphenol removal in diluted OMWW is facilitated at relatively low pH and intermediate H2O2 values. A predicted value of 50.7 ± 9.5% removal was calculated under optimal operational conditions (pH 2.76, [H2O2] = 3.56 mM). Analysis of an untreated and an optimally treated sample by high performance liquid chromatography revealed that enzyme treatment brought about alteration in the original OMWW polyphenolic profile. The use of peroxidase from onion solid by-products is proposed as an alternative means that could have a prospect in bioremediation applications.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号