E1 Effluent Research Articles

Trametes versicolour laccase immobilization by covalent binding and its application in Kraft E1 effluent pre-treated with ozone

Wastewater deriving from cellulose and paper manufacturing is one of the most important industrial effluents due to its large-volume production and high pollution load. Effluent deriving from the pulp bleaching stage (Kraft E1 effluent) remains one of the major issues faced by paper mills among all wastewaters generated in each stage of paper-making processes. Kraft E1 effluent was submitted to a sequential chemical (ozonization) – biological (immobilized laccase) treatment. Laccase was obtained from Trametes versicolour in liquid medium of culture using 2,5 -xylidine as inducer. Crude laccase extract was immobilized through covalent binding in Montmorillonite KSF and Eupergit®C supports based on different protocols. Eupergit®C has shown the best protein immobilization (51%), retention activity (100%), and operational stability (ten oxidative cycles) results. Enzymatic treatments using free and immobilized laccase onto Eupergit®C were applied to Kraft E1 effluent. After 18-h treatment, total phenol removal reached 20% and 40% in free and immobilized laccase, respectively. Ozone combined to enzymatic processes using reactor assembled with immobilized laccase (31 U g−1, total mass = 10.0 g) had effect on decolonization efficiency and on total phenols’ removal from Kraft effluent. Ozone treatment was capable of removing 52% of total phenols and 76% of colour from the investigated effluent. Sequential enzymatic treatment has increased total phenols’ removal to 64% within 30-minute treatment and reached 70% removal within 60 minutes. The herein observed additional phenol removal based on enzymatic treatment is an important outcome if one takes into consideration the fraction of total phenols that could not be removed by the ozone process.

Studies on coupled biological and photochemical treatment of soda pulp bleaching effluents from agro residue based pulp and paper mill

AbstractBACKGROUND: The effect of coupled biological and photochemical processes for treatment of bio‐recalcitrant effluents from chlorination (C) and first alkaline extraction (E1) stages of soda pulp bleaching in an agro‐residue based pulp and paper mill has been investigated.RESULTS: The work aims to evaluate the coupled effect on the extent of degradation in terms of chemical oxygen demand (COD) reduction. Biological treatment of C and E1 effluent resulted in 30% and 57% COD, respectively, after 1 day of treatment with acclimatized activated sludge. However, further increase in retention time did not show any significant change in degradation efficiency. Investigations on photocatalytic treatment (at 365 nm and 0.625 W) of C effluent resulted in 47% degradation under optimized conditions (3 g L−1 TiO2, pH 6.0 and 0.01 mol L−1 NaOCl), and E1 effluent showed 37% degradation under optimized conditions (2.5 g L−1, pH 4.0 and 0.03 mol L−1 NaOCl) after 6 h of UV irradiation. However, photocatalytic treatment of biotreated (1 day) effluents under similar optimized conditions significantly enhanced the degradation to 81% and 93% in C and E1 effluent, respectively, after 2 h irradiation.CONCLUSION: Coupled biological treatment followed by photocatalysis is an effective method for the reduction of total organic carbon (TOC) of the test effluents and it would facilitate closed circuiting of water used for soda bleaching in an agro pulp and paper mill. Copyright © 2011 Society of Chemical Industry

Fungal laccase: copper induction, semi-purification, immobilization, phenolic effluent treatment and electrochemical measurement

The laccase activity induced by copper ions in Trametes versicolor by two inducers was studied and the aims were to show that it is possible to obtain a high laccase activity in almost 12 of the enzymes product using a basic culture medium but different copper concentration. Laccase was inducted by 2,5-xylidine and copper sulfate. Semi-purification of the crude laccase was carried out through precipitation and the column separation with NaCl gradient. In order to apply in an effluent treatment, laccase was immobilized on different vitroceramics supports, pyrolytic graphite and also on a carbon fiber electrode as biosensor. The maximum laccase activity was 40,774.0 U L-1 at the 12th day. The best support for immobilization was pyrolytic graphite (glutaraldehyde treated-94% efficiency). Total phenol removal in Kraft E1 effluent was 19% for immobilized pyrolytic graphite with the mediator present. The biosensor prepared with this material showed a good linear response to catechol. The optimization of laccase activity induction through the combination of 2,5-xylidine and cooper sulfate was obtained and led to its use in environmental remediation. Key words: Trametes versicolor, laccase induction, semi-purification, immobilization, effluent treatment.

Toxicity Assay in Kraft E1 Effluent Treated by Ozone: Algae Growth Inhibition and Cytotoxicity in V79 Cells

The efficiency of an ozonation process in the degradation of the Kraft E1 effluent was evaluated. The investigation was focused on the reduction of chemical oxygen demand, total phenols, color and the absorbance at 254 nm. The chronic toxicity was evaluated by growth inhibition of algae Selenatrum capricornutum and cytotoxicity evaluation of effluents samples by determination of the nucleic acid content (NCA) endpoint. After 60 minutes of ozonation, COD and UV254 only reached 21% and 34% efficiency reduction. Total phenols and color were more rapidly removed (at 10 minutes of treatment). The results showed that the chronic toxicity (Selenastrum capricornutum algae) decreases for all effluent doses studied. The cytotoxicity assay indicated that toxic compounds were not generated by the ozonation process.

Fungal laccase: copper induction, semi-purification, immobilization, phenolic effluent treatment and electrochemical measurement

The laccase activity induced by copper ions in Trametes versicolor by two inducers was studied and the aims were to show that it is possible to obtain a high laccase activity in almost 12 of the enzymes product using a basic culture medium but different copper concentration. Laccase was inducted by 2,5-xylidine and copper sulfate. Semi-purification of the crude laccase was carried out through precipitation and the column separation with NaCl gradient. In order to apply in an effluent treatment, laccase was immobilized on different vitroceramics supports, pyrolytic graphite and also on a carbon fiber electrode as biosensor. The maximum laccase activity was 40,774.0 U L-1 at the 12th day. The best support for immobilization was pyrolytic graphite (glutaraldehyde treated-94% efficiency). Total phenol removal in Kraft E1 effluent was 19% for immobilized pyrolytic graphite with the mediator present. The biosensor prepared with this material showed a good linear response to catechol. The optimization of laccase activity induction through the combination of 2,5-xylidine and cooper sulfate was obtained and led to its use in environmental remediation.

Remediation of Kraft Effluent by Ozonation: Effect of Applied Ozone Concentration and Initial pH

ABSTRACT In this study, the impact of ozone concentration (14 and 7mg/L−1 applied for 120min) and pH (10 and 12) on color removal, and reduction of dissolved organic matter (DOC) and total phenol of Kraft E1 effluent was investigated. The degradation kinetics for the all parameters at pH 12 were slower than of those at pH 10. The degradation at pH 10 ceased after approximately 120min, while for the ozonation at pH 12, ozone was still being consumed even after 5h of treatment. When the ozone dose was increased, the removal efficiency increased; however, the DOC removal efficiency continued limited.

Treatment of the effluent from a kraft bleach plant with the white-rot fungus Pleurotus ostreatoroseus sing

The ligninolytic fungus Pleurotus ostreatoroseus (synonymy of Pleurotus ëous) was used to treat the first alkali extraction stage (E1) effluent of a kraft bleach plant. It was pelletized and used for two continuous experiments in a two-liter turbulent-flow bioreactor. In the first experiment, the average removal of color and of total phenols was 18.6 and 11.6%, respectively, after the addition of glucose. During the second experiment, which was developed with the addition of several quantities of glucose, the maximum removal of color, of total phenols and of lignin/chlorolignin was 19.4, 9.4 and 44.5%. For both experiments, the best results were obtained when the effluent was diluted and enriched with glucose. This indicated the need for an extra carbon source for the fungal treatment. Using the mycelial mass in suspension, three experiments were carried out. The best results were obtained with 20% fungus and shaking of the effluent. During the last three days of the experiment the average removal of color, of total phenols and of lignin/chlorolignin was 84.4± 6.1, 82.1± 5.7 and 72.4± 8.9, respectively. The results indicate the potential of Pleurotus ostreatoroseus for use in the treatment of E1 effluent.

Biodegradation of chlorolignin and lignin-like compounds contained in E1-pulp bleaching effluent by fungal treatment.

The ligninolytic system from the fungi Trametes villosa and Panus crinitus can efficiently degrade all fractions of different molecular mass contained in E1-bleaching effluent, but with different degradation rates. The lower-molecular-mass (MM) materials were better characterized when the elution in the size-exclusion high-performance liquid chromatography were monitored at 210 than at 280 nm, which indicates that these compounds may be ring cleavage byproducts from depolymerized chlorolignin. The biodegradation of E1 effluent by both fungi was a multistage process, involving an initial chemical modification of the higher-MM compounds and concomitant oxidation of the lower-MM materials. A subsequent depolymerization of chemically modified polymeric lignin-like compounds also took place. Each stage may require one or several different enzymes. The results suggested that laccase was involved in the initial stage.

Some Chemical and Toxicological Aspects about Paper Mill Effluent Treatment with Ozone

The paper mill industry produces high effluent volumes that normally cause a high environmental impact. In this work, Kraft E1 effluent was treated with ozone and some chemical parameters (total organic carbon, molecular mass distribution and total phenols) were analysed at different ozonization times. The toxicity of the effluent was determinated during the ozonization process, using the bacterium Escherichia coli, by a respirometric test. After sixty minutes of ozonization, total organic carbon decreased to around 12%, total phenols to 70% and effluent colour to 35%. The effluent molecular mass was significantly reduced during the process and the toxicity to E. coli decreased with effluent ozonization.

Semiconductor-assisted photodegradation of lignin, dye, and kraft effluent by Ag-doped ZnO

This work reports a preliminary study of semiconductor-assisted photochemical degradation of lignin, Remazol Brilliant Blue R and Kraft E1 paper effluent by using ZnO and Ag-doped ZnO photocatalysts. The doped semiconductor was prepared in the reaction media by photoreduction of silver nitrate. With the use of 100 mg of ZnO and 15 mg of Ag–ZnO, almost total decolorization of the dye and lignin samples in reaction times lower than 60 min were observed. Extending the photochemical reaction up to 120 min, the total organic carbon content (TOC) was reduced in 90%. For the paper effluent, a fast decolorization was obtained for relatively short reaction times. However, de TOC reduction was negligible (near of 10%) up to high reaction times (300 min). By using the Ag–ZnO photocatalyst, the toxicity of lignin and Kraft E1 effluent toward E. Coli was completely removed. For the dye, the formation of transient toxic species was observed.

Degradation of Low and High Molecular Mass Fractions of Kraft E1 Effluent by Trametes Villosa

A very efficient Trametes villosa strain was selected from a screening in our laboratories, which exhibited a high capability of bleaching effluent (E1) biodegradation. This fungus decolorized 70–80% in 24–48h incubation time and degraded 80% of total phenol acting on E1 effluent. Size exclusion high pressure liquid chromatography (HPLC) showed that 75% of total color can be attributed to the high-molecular mass materials (MM> 15000 Da). The change in the MM distribution during the incubation period showed evidence that both high and low molecular mass fractions were biodegraded by the fungal treatment. The HPLC analyses of the original E1 effluent (MM< 1000 Da) revealed that four compounds were responsible for 99% of the sample composition.

Decolorization of Pulp Mill Effluents with Immobilized Lignin and Manganese Peroxidase from Phanerochaete Chrysosporium

The immobilization of lignin and manganese peroxidase produced by Phanerochaete chrysosporium on Amberlite IRA-400 resin and its utilization on the remediation of effluents from the pulp and paper industry was evaluated. The ion exchange resin shows great efficiency for the enzyme immobilization, allowing almost total enzymatic activity retention in a short period at (30 min). The immobilized enzyme was very efficient to removing colour and phenolic species from Kraft E1 effluent with insignificant adsorption of coloured species by the support. Effluent decolorization of over 50% for 3 h of enzymatic treatment was obtained. For bleaching mixture effluent and black liquor, substantial decolorization ratios were also observed. Unfortunately, a considerable fraction of this decolorization was due to adsorption on the resin surface.

Effluent Treatment of Pulp and Paper, and Textile Industries using Immobilised Horseradish Peroxidase

Horseradish peroxidase immobilisation on several supports and its utilisation for decontamination of effluent from paper and textile industries was evaluated. Among the supports, Amberlite IRA-400 ion exchange resin showed the best results for enzyme immobilisation, efficiency of colour removal and degradation of phenolic species from Kraft E1 effluent (first alkaline extraction), bleaching mixture effluent and black liquor. Effluent decolorisations over 50% were obtained after 4 h of enzymatic treatment, without significant adsorption of coloured species by the support. Decolorisation in pre-irradiated Kraft E1 effluent was kinetically more efficient than in a non-irradiated one. For this reason, the combined photo-enzymatic decolorisation procedure appears to be an efficient decontamination method with great potential for industrial effluent treatment.

Adsorption effects in the decolorization of a Kraft bleach plant effluent by Phanerochaete chrysosporium

Phanerochaete chrysosporium was proposed for the decolorization and degradation of chlorinated compounds (AOX) present in the E1 stage effluent of the Kraft process. We observed that pellets of the fungus inoculated in the E1 effluent, not supplemented with nutrients, strongly absorb colour and AOX. The data were in agreement with a model describing a multilayer adsorption.

The role of ultrafiltration and nanofiltration on the minimisation of the environmental impact of bleached pulp effluents

Today the bleaching stages of the pulp industry are faced with an enormous challenge concerning the minimisation of the environmental impact of its effluents. Organochlorinated compounds (TOX) and mainly the low-molecular-weight fraction of the extractable compounds (EOX) are major pollutants because of their lipophilicity and bioaccumulation ability. This work evaluates the performance of ultrafiltration (UF) and nanofiltration (NF) on the reduction of organochlorinated matter and colour in the effluents from the first alkaline extraction (E1) of two different bleaching sequences, one with chlorine/chlorine dioxide and the other only with chlorine dioxide. Three types of membranes were used. Ultrafiltration membranes, CA-400 and ETNA01A, and nanofiltration membranes, CDNF50. The substitution of chlorine/chlorine dioxide by chlorine dioxide in the first bleaching stage reduces 84% of EOX, 82% of TOX and 72% of colour in the E1 effluent. The highest removal of TOX and colour achieved by ultrafiltration is 72 and 92%, respectively. The total removal of colour and more than 90% removal of TOX is achieved by nanofiltration. The two operations, by themselves or integrated, can serve the regulatory and/or mill demands.

A new alternative process for Kraft E1 effluent treatment

Lentinus edodes (UEC-2019 strain) was selected after screening 51 ligninolytic strains of fungi for their ability to decolorize phenolic industrial effluent with high content of lignin peroxidases, Mn-peroxidases and beta-glucosidases. This strain removed 73 % of color in theEucalyptus Kraft E1 effluent in 5 days without any additional carbon sources. A 13% mycelial adsorption was found. Correlation between mass loss, COD, TOC and decolorization was observed. When an effluent pre-irradiated (10 min) in the presence of ZnO was treated withL. edodes, a marked enhancement of the decolorization at 48 h was obtained.L. edodes is an active fungus in this pre-treatment and biobleaching process. The combined photo-biological decolorization procedure appears to be an efficient decontamination method with great potential in industrial effluent treatment.

Screening of white-rot fungi for efficient decolourization of bleach pulp effluents

Several white-rot fungi collected in the South of Chile were evaluated for their ability to decolourize kraft pulp bleached effluents. Strain 158, recently identified as aRamaria sp., showed the highest potential for the biological treatment of E1 effluent: 90% of the colour was removed by this strain grown under air, with a similar rate and extent of decolourization asPhanerochaete chrysosporium, under oxygen.

4692413 Use of rLDM£198 +0 1 + 14 6 and other ligninolytic enzymes for the decolorization of E1 effluent: Roberta L Farrell assigned to Repligen Corporation

4692413 Use of rLDM£198 +0 1 + 14 6 and other ligninolytic enzymes for the decolorization of E1 effluent: Roberta L Farrell assigned to Repligen Corporation