PAPERmaking! g FROM THE PUBLISHERS OF PAPER TECHNOLOGY Volume 2, Number 1, 2016
Chlorophenol concentration Chlorophenols are important biocides and as by-product of bleaching in the pulp and paper industry. Their widespread use has resulted in broad distribution of these compounds in the environment. Environmental contamination with chlorophenols is widespread due to the importance of these chemicals as industrial intermediate, pesticides and solvents. Eisenia fetida can be a significant fate for the chlorophenol removal because physical and chemical methods are not feasible due to high cost and generate secondary pollutants and a single microorganism is unable to mineralise a wide range of different chlorophenols. Field and Sierra-Alvarez (2008) wrote a comprehensive review on the aerobic and anaerobic biotransformation of chlorophenols by microorganism. From the present result, we found that all the 12 different chlorophenols decreased significantly as compared to control having very high concentration (Table 4). Chlorophenols were decreased gradually with time; at 90 days from all the three sets, we did not observe any chlorophenols from the sample whereas in control chlorophenols, concentration was remaining the same (Table 4). From the 2nd experiment having spiked concentration of PCP about (100mg/kg) after 90 days, we found that there is also significant decrease in the concentration of PCP and left about 0.02mg/kg, which shows that vermicomposting having high potential for the removal of chlorophenol from the pulp and paper mill sludge. It is well-established that a large number of organic wastes can be ingested by earthworm and egested as peat-like material termed as vermicompost. Edwards (1988); Kaushik and Garg (2003, 2004) have reported the vermicomposting of textile mill sludge using Eisenia fetida . Butt (1993) showed that solid paper mill sludge was a suitable feed for Lumbricus terrestis under laboratory conditions. Elvira et al. (1998) have reported vermicomposting of paper mill sludge using Eisenia Andrei under laboratory as well as field conditions and found suitable for mineralisation and compost formation. Some report also indicates that other annelids, such as aquatic Polychaetes, can metabolise benzopyrene, because they possess cytrochrome P450 enzymes capable of degrading this compound (Driscoll and McElroy 1997). The same enzymatic activity was found in terrestrial earthworms such as Eisenia fetida (Achazi et al. 1998). This may be a reason for Eisenia fetida to remove organic compounds and metabolise successfully. Autochthonous microorganisms degrade hydrocarbons (Johnsen et al. 2005), but if earthworms are added to soil, they will improve aeration, and stimulate microbial activity, thus increasing biodegradation. Eijsackers et al. (2001) reported that there was a steady decrease in the concentrations of Phenenthrene in soil when they added worms and only very low concentrations of Phenanthrene were detected after 40 days.
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Article 2 – Treating Paper Mill Sludge
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