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Treatment of Pulp and Paper Mill Effluent Using Photo-fenton`s Process  [PDF]
A.Y. Zahrim,Melissa L. Gilbert,Jidon Janaun
Journal of Applied Sciences , 2007,
Abstract: Wastewater from pulp and paper mill is one of the most important sources of pollutants mainly due to the pulping and bleaching processes. This study evaluates the effectiveness of photo-Fenton`s process in reducing organic and suspended solid in pulp and paper mill wastewater. The photo-Fenton`s process produces the strongest oxidation and consumes lower Fe2+ compared to the conventional Fenton`s process. The conditions of the photo-Fenton`s process were optimized such as the initial pH, the H2O2 concentration and the FeSO4.7H2O concentration. It was found that the optimal pH for Fenton`s process was pH 5. The optimal initial concentration of H2O2 and FeSO4.7H2O were 500 and 400 mg L-1, respectively. The overall efficiency of BOD3 and TSS reduced by the Fenton`s process under optimal conditions attained up to 87.5 and 87.0%, respectively. Thus, the photo-Fenton`s process has the potential to be used in the treatment of pulp and paper effluent.
Engineering bacterial strains through the chromosomal insertion of the chlorocatechol catabolism tfdI CDEF gene cluster, to improve degradation of typical bleached Kraft pulp mill effluent pollutants
Bobadilla,Roberto; Varela,Cristián; Céspedes,Ricardo; González,Bernardo;
Electronic Journal of Biotechnology , 2002,
Abstract: chloroaromatic pollutants from bleached kraft pulp mill effluents (bkme) are difficult to degrade, because bacterial strains present in bkme aerobic treatments, only partially degrade these compounds, accumulating the corresponding chlorocatechol intermediates. to improve the catabolic performance of chlorocatechol-accumulating strains, we introduced, by chromosomal insertion, the tfdicdef gene cluster from ralstonia eutropha jmp134 (pjp4). this gene cluster allows dechlorination and channelling of chlorocatechols into the intermediate metabolism. two bacterial strains, r. eutropha jmp222 and pseudomonas putida kt2442, able to produce chlorocatechols from 3-chlorobenzoate (3-cb) were used. acinetobacter lwoffii rb2 isolated from bkme by its ability to grow on guaiacol as sole carbon source and shown to be able to produce the corresponding chlorocatechols from the bkme pollutants 4-, and 5-chloroguaiacol, was also used. the tfdicdef gene cluster was inserted in the chromosome of these strains using minitn5-derived vectors that allow expression of the tfd enzymes driven by the laciq/ptrc or tfdr/ptfd-i regulatory systems, and therefore, responding to the inducers isopropyl-?-d-thiogalactopyranoside (iptg) or 3-cb, respectively. crude extracts of cells from strains jmp222, kt2442 or rb2 engineered with the tfd genes, grown on benzoate and induced with iptg or 3-cb showed tfd specific activities of about 15% - 80% of that of the strain jmp134. dechlorination rates for 3-cb or chloroguaiacols correlated with levels of tfd enzymes. however, none of the strains containing the chromosomal copy of the tfdicdef cluster grew on monochloroaromatics as sole carbon source. experiments with bkme aerobic treatment microcosms showed that the catabolic performance of the engineered bacteria was also lower than the wild-type r. eutropha strain jmp134.
The electro-oxidation of lignin in Sappi Saiccor dissolving pulp mill effluent
B Moodley, DA Mulholland, HC Brookes
Water SA , 2011,
Abstract: Electro-oxidation reactions using a nickel anode were carried out on the calcium-spent liquor effluent obtained from Sappi Saiccor (formerly South African Industrial Cellulose Corporation) dissolving pulp mill as well as on lignin- and lignan-type compounds previously identified in the effluent. Voltammograms were obtained for each solution in order to identify the oxidation potentials of the compounds to be electro-oxidised. Value-added products such as vanillin and syringaldehyde were identified in the electro-oxidised reaction mixtures using gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC). Profiles of the changes in concentration of these compounds were determined as a function of time with maximum concentrations reached within the first half hour. These findings are significant in that few electro-oxidation reactions have been carried out on the effluent of a pulp mill which uses the acid bisulphite pulping process and no results have previously been reported on the electro-oxidation of syringaldehyde. This study contributes to a further understanding of the electro-oxidation of lignin and is of value to the paper and pulp industry at large. Reduction of the organic content of the effluent by electro-oxidation was shown to be possible.
Investigation on Microorganisms and their Degradation Efficiency in Paper and Pulp Mill Effluent  [PDF]
Radhakrishnan Saraswathi, Manghatai Kesavan Saseetharan
Journal of Water Resource and Protection (JWARP) , 2010, DOI: 10.4236/jwarp.2010.27076
Abstract: Paper and pulp mill is a source of major pollution generating industry leaving huge amount of intensely colored effluent to the receiving end. Rapid increase of population and the increased demand for industrial establishments to meet human needs have created problems such as over exploitation of available resources, increased pollution taking place on land, air and water environment. The intention of this research paper is to identify predominant bacteria and fungi in paper and pulp mill effluent in addition to evaluate the degradation efficiency of individual isolates and combination of isolates. Treatment efficiency of individual isolates and combination of isolates are evaluated by shake flask method. Combination of Pseudomonas Alkaligenes, Bacillus subtilis along with Trichoderma reesei shows higher BOD, COD reduction of 99% and 85% respectively. As individual isolates Pseudomonas Alkaligenes show 92% BOD reduction and 77% COD reduction over other bacterial isolates and Trichoderma reesei removed 99% BOD and 80% COD respectively.
The chemical oxidation of lignin found in Sappi Saiccor dissolving pulp mill effluent
B Moodley, DA Mulholland, HC Brookes
Water SA , 2012,
Abstract: Sappi Saiccor (situated in Durban, South Africa) dissolving pulp mill effluent, produced from an acid bisulphite pulping process, uses acacia and eucalyptus hardwoods to produce a unique and different blend of lignin that has not been previously studied. The chemical oxidation of lignin found in Sappi Saiccor’s effluent has been investigated using a number of different chemical oxidising agents, such as nitrobenzene, oxygen with and without the presence of a copper sulphate pentahydrate catalyst, and hydrogen peroxide. The reaction products were extracted with acid and identified using GC-MS and LC-MS techniques. Nitrobenzene is a good oxidising agent but tends to produce many toxic by-products and would not be acceptable on an industrial scale. Oxygen oxidation has previously been shown to produce aldehyde-type compounds, and in this work has produced good yields of both vanillin and syringaldehyde compared to previous oxygen oxidation reactions. Hydrogen peroxide is a strong oxidising agent that tends to over-oxidise the lignin during long reaction times.
Ravi Dutt Yadav,Smita Chaudhry,Saurabh Sudha Dhiman
BioResources , 2010,
Abstract: Mixed hardwood chips were treated with lignin-degrading fungi to study the effect of fungal pretreatment on bleaching characteristics of kraft pulp. Pretreated wood chips were subjected to reduced active alkali doses in comparison to untreated chips. Comparable results were obtained for pretreated chips with reduced alkali dose as was obtained with higher dose of alkali in case of untreated chips. Fungal treatment made the process more energy-efficient, and 4.8% less chlorine was consumed in comparison to the control process. Pretreatment with Ceriporiopsis subvermispora was responsible for reduction of 4.7% in lignin contents, 14.3% permanganate number, and overall reduction of 15.5 kg/T of Cl2 consumption. The pollution load in terms of COD and BOD at the CD stage was reduced by 32.6% and 41.5% respectively, whereas 12% reduction in AOX compounds was observed in effluent of pretreated pulp.
Modeling energy consumption for the generation of microfibres from bleached kraft pulp fibres in a PFI mill  [cached]
Chakraborty, A.,Sain, M. M.,Kortschot, M. T.,Ghosh, S. B.
BioResources , 2007,
Abstract: The objective of this paper is to model the energy consumed in generating cellulose microfibres, 1 μm in diameter, as reinforcing agents, by refining bleached softwood kraft pulp in a PFI mill. An average initial fibre diameter of 13 μm was assumed. 125,000 revolutions in a PFI mill was found to produce a high yield of fibres 1.3 μm in diameter, and the minimum refining energy needed to reduce the fibre diameter to 1.3 μm was estimated as 1875 kJ for each 24 g charge in the PFI mill. Since elastic deformation of the fibres was found to be negligible, the size reduction was assumed to follow Rittinger’s Law. This gave a Rittinger’s constant of 28 J.m/kg for the given system. Using this value of Rittinger’s constant, the energy required to generate microfibres 1 μm in diameter was predicted as 2480 kJ for each 24 g charge in the PFI mill. It was deduced that microfibres generated in this way would cost a minimum of $2.37 per kilogram. Hence even this relatively inefficient method of grinding would not be prohibitively expensive, provided the resulting microfibres can be used as high quality reinforcements.
Degradation of pulp and paper-mill effluent by thermophilic micro-organisms using batch systems
Prenaven Reddy, Visvanathan L Pillay, Adinarayana Kunamneni, Suren Singh
Water SA , 2005,
Abstract: Paper manufacturers produce large quantities of wastewater, which can have deleterious effects on the receiving waters; therefore there is a need to find a treatment process which can minimize these effects considerably. A suitable aerobic biological treatment process that can be used with great success involves the use of thermophilic micro-organisms. This technology has many advantages, which include rapid biodegradation rates, low sludge yields, and excellent process stability. Batch studies were conducted on two types of activated sludge (pulp-mill sludge and sewage sludge) at 40°C, 50°C and 60°C to determine the feasibility of thermophilic degradation of bleach pulp-mill effluent in terms of increasing aeration, biomass concentration and nutrient addition. Preliminary batch studies had confirmed the feasibility of thermophilic degradation, as COD removal achieved with the pulp-mill sludge was 55.2%, 37.6% and 31.4% at 40°C, 50°C and 60°C after 5d, respectively while the COD removal with sewage sludge was 50.2%, 37.3% and 27% under the same conditions. Degradation was further improved, using the same inocula in subsequent experiments and this confirmed that an acclimatization period is required, prior to degrading the bleach pulp-mill effluent. Thermophilic degradation of pulp-mill effluent occurs at temperatures of up to 60°C; however, once final degradation is obtained, it decreases significantly as temperature increases.
Optimal Condition of Fenton's Reagent to Enhance the Alcohol Production from Palm Oil Mill Effluent (POME)
Supawadee Sinnaraprasat,Prayoon Fongsatitkul
EnvironmentAsia , 2011,
Abstract: Application of Fenton's reaction for a proper hydrolysis step is an essential and important step in obtaining a higher level of readily biodegradable sugars from palm oil mill effluent (POME) for improving the alcohol production by using immobilized Clostridium acetobutylicum. The objective of this research was, therefore, to investigate the optimum condition of Fenton's reaction in terms of COD: H2O2 ratios (w/w) and H2O2: Fe2+ ratios (molar ratio) used to oxidize carbohydrate and high molecular organic compounds into simple sugars, which are further fermented into alcohol. The experiments were carried out at H2O2: Fe2+ ratios (molar ratios) of 5, 10, 20, 30 and 40 and the COD: H2O2 ratios (w/w) of 50, 70, 100 and 130 (initial COD about 50,000 mg/L). The total sugar concentrations and organic compounds biodegradability (BOD5/COD ratios) were also used for investigating suitable conditions for Fenton's reaction. The concentration of Fenton's reagent at H2O2:Fe2+ and COD:H2O2 ratio of 20 and 130 was identified as the optimum operating condition for the highest simple sugars of about 0.865% and BOD5/COD ratios of 0.539. The alcohol productions were carried out in the continuous stirred tank reactors (CSTR) under an anaerobic continuous immobilization system. At a hydraulic retention time of 12 hours and POME pH of 4.8, the maximum total ABE concentration of 495 mg/L and the ABE yield of 0.236 grams of ABE produced/gram of reducing sugars were achieved at the mixed polyvinyl alcohol (PVA) and palm oil ash (POA) ratio of 10 : 3.
Golden Research Thoughts , 2013, DOI: 10.9780/22315063
Abstract: The present work was carried out to monitor the impact of paper effluent on themicrobial diversity viz., bacteria, fungi and cyanobacteria. Results of one yearecological study revealed that altogether 10 species of bacteria, 5 species of fungi and 42species of cyanobacteria were isolated from the effluent stream. Among the bacteria,Pseudomonas with two species and others with single species each were recorded.Aspergillus was dominant among fungi with 2 species followed by Penicillium withthree. Cyanobacteria, one of the dominant group of algae, inhabiting all kinds of water(effluents), recorded 42 species. Oscillatoria with 14 species was the dominant genusfollowed by Lyngbya (8), Phormedium (4), Chroococcus and Microcystis with twospecies each. Higher amounts of phosphates and nitrates, with sufficient amount ofoxidizable organic matter, limited dissolved oxygen content and slightly alkaline pHwere probably the factors favoring the growth of microbes especially cyanobacteria. Theutilization of dominant species of cyanobacteria to monitor pollution in Paper milleffluent has also been discussed.
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