S. R. Wate

Removal of probable human carcinogenic polycyclic aromatic hydrocarbons from contaminated water using molecularly imprinted polymer.

A molecularly imprinted polymer (MIP) adsorbent for carcinogenic polycyclic aromatic hydrocarbons (PAHs) was prepared using a non-covalent templating technique. MIP particles sized from 2 to 5 microm were synthesized in acetonitrile by using six PAHs mix as a template, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. When compared with the non-imprinted polymer (NIP), the MIP showed an excellent affinity towards PAHs in aqueous solution with binding capacity (B(max)) of 687 microg g(-1)MIP, imprinting effect of 6, and a dissociation constant of 24 microM. The MIP exhibited significant binding affinity towards PAHs even in the presence of environmental parameters such as dissolved organic matter (COD) and total dissolved inorganic solids (TDS), suggesting that this material may be appropriate for removal of carcinogenic PAHs. The feasibility of removing PAHs from water by the MIP demonstrated using groundwater spiked with PAHs. In addition, the MIP reusability without any deterioration in performance was demonstrated at least ten repeated cycles.

Kinetic study approach of remazol black-B use for the development of two-stage anoxic–oxic reactor for decolorization/biodegradation of azo dyes by activated bacterial consortium

The laboratory-isolated strains Pseudomonas aeruginosa, Rhodobacter sphaeroides, Proteus mirabilis, Bacillus circulance, NAD 1 and NAD 6 were observed to be predominant in the bacterial consortium responsible for effective decolorization of the azo dyes. The kinetic characteristics of azo dye decolorization by bacterial consortium were determined quantitatively using reactive vinyl sulfonated diazo dye, remazol black-B (RB-B) as a model substrate. Effects of substrate (RB-B) concentration as well as different substrates (azo dyes), environmental parameters (temperature and pH), glucose and other electron donor/co-substrate on the rate of decolorization were investigated to reveal the key factor that determines the performance of dye decolorization. The activation energy (E(a)) and frequency factor (K(0)) based on the Arrhenius equation was calculated as 11.67 kcal mol(-1) and 1.57 x 10(7)mg lg MLSS(-1)h(-1), respectively. The Double-reciprocal or Lineweaver-Burk plot was used to evaluate V(max), 15.97 h(-1) and K(m), 85.66 mg l(-1). The two-stage anoxic-oxic reactor system has proved to be successful in achieving significant decolorization and degradation of azo dyes by specific developed bacterial consortium with a removal of 84% color and 80% COD for real textile effluents vis-à-vis >or=90% color and COD removal for synthetic dye solution.

Selection of indicator bacteria based on screening of 16S rDNA metagenomic library from a two-stage anoxic-oxic bioreactor system degrading azo dyes.

Dye degradation has gained attention of late due to indiscriminate disposal from user industries. Enhancing efficiency of biological treatment provides a cheaper alternative vis-à-vis other advanced technologies. Dye molecules are metabolized biologically via anoxic and oxic treatments. In this study, bacterial community surviving on dye effluent working in anoxic-oxic bioreactor was analyzed using 16S rDNA approach. Azo-dye decolorizing and degrading bacterial community was enriched in lab-scale two-stage anoxic-oxic bioreactor. 16S rDNA metagenomic libraries of enriched population were constructed, screened and phylogenetically analyzed separately. Removal of approximately 35% COD with complete decolorization was observed in anoxic bioreactor. Process was carried out by uncultured gamma proteobacterium constituting 48% of the total population and 12% clones having homology to Klebsiella. Aromatic amines generated during partial treatment under anoxic bioreactor were treated by aerobic population having 72% unculturable unidentified bacterium and rest of the population consisting of Thauera sp., Pseudoxanthomonas sp., Desulfomicrobium sp., Ottowia sp., Acidovorax sp., and Bacteriodetes bacterium sp.

Energy efficient--advanced oxidation process for treatment of cyanide containing automobile industry wastewater.

Destruction of cyanide (CN) from an automobile industry wastewater by advance oxidation process (AOP) has been evaluated. The operating conditions (in an indigenously designed photoreactor) for three different treatment strategies have been optimized. The treatment strategies involved use of, ultra violet light (UV), hydrogen peroxide (H(2)O(2)) and ozone (O(3)) in various combinations. Treatment of automobile industry wastewater (250 mg/L CN) showed fastest CN destruction, which was significantly (P<0.05) faster than that observed with synthetic wastewater (with similar CN concentration). A combined application of H(2)O(2)/O(3) was found to be the best option for maximum CN destruction. This treatment allows CN to reach the regional/international limit (of 0.02 mg/L) for safe industrial wastewater discharges to the receiving water bodies. The specific energy consumption by the photoreactor following this treatment was comparable to that obtained by conventional treatments, which use photocatalyst. Since the present treatment does not use catalyst, it provides an excellent energy efficient and economical option for treatment and safe disposal of CN containing industrial wastewater.

Pretreatment of banana agricultural waste for bio-ethanol production: individual and interactive effects of acid and alkali pretreatments with autoclaving, microwave heating and ultrasonication.

Banana agricultural waste is one of the potential lignocellulosic substrates which are mostly un-utilized but sufficiently available in many parts of the world. In the present study, suitability of banana waste for biofuel production with respect to pretreatment and reducing sugar yield was assessed. The effectiveness of both acid and alkali pretreatments along with autoclaving, microwave heating and ultrasonication on different morphological parts of banana (BMPs) was studied. The data were statistically analyzed using ANOVA and numerical point prediction tool of MINITAB RELEASE 14. Accordingly, the optimum cumulative conditions for maximum recovery of reducing sugar through acid pretreatment are: leaf (LF) as the substrate with 25 min of reaction time and 180°C of reaction temperature using microwave. Whereas, the optimum conditions for alkaline pretreatments are: pith (PH) as the substrate with 51 min of reaction time and 50°C of reaction temperature using ultrasonication (US).

How safe are the global water coverage figures? Case study from Madhya Pradesh, India

The World Health Organization (WHO)/United Nations Children’s Fund (UNICEF) Joint Monitoring Programme (JMP) for Water Supply and Sanitation was designed to provide reference figures for access in individual countries to safe water. The JMP is based on non-administrative or nongovernment data from national-level surveys such as the Multiple Indicator Clusters Survey (MICS) or Demographic Health Survey. In the 2007 JMP report, India is noted to have water supply coverage of 89% (95% in urban areas and 85% in rural areas) compared to the Government of India estimates of 95%. The central state of Madhya Pradesh is noted by the Government of India to have coverage of 60%. However, the definition of access to safe water currently does not consider the quality or safety of the water being consumed. This paper, therefore, presents results from the application of a statistical tool (random multiple cluster technique—termed Rapid Assessment of Drinking Water Quality [RADWQ]) to Indore Zone in Madhya Pradesh. When results provided by the RADWQ technique are compared to the JMP MICS data, coverage levels reported in the JMP are reduced by up to 40% due to the high risk of microbiological (thermotolerant coliforms) contamination. In Indore Zone, the coverage of safe water reduced from 42% to 25% through the inclusion of the water safety parameters. The study recommends the inclusion of water quality/safety data in reported data under the UNICEF/WHO JMP.

Groundwater quality and water quality index at Bhandara District

The present investigation reports the results of a monitoring study focusing on groundwater quality of Bhandara District of central India. Since, remediation of groundwater is very difficult, knowledge of the existing nature, magnitude, and sources of the various pollution loads is a prerequisite to assessing groundwater quality. The water quality index (WQI) value as a function of various physicochemical and bacteriological parameters was determined for groundwater obtained from a total of 21 locations. The WQI during pre-monsoon season varied from 68 to 83, while for post-monsoon, it was between 56 and 76. Significantly (P < 0.01) lower WQI for the post-monsoon season was observed, indicating deterioration of the groundwater overall in corresponding season. The study revealed that groundwater from only 19% locations was fit for domestic use, thus indicating the need of proper treatment before use.

Vermifilters: a tool for aerobic biological treatment of herbal pharmaceutical wastewater

Herbal pharmaceutical wastewater possesses high chemical oxygen demand (COD) (21,960-26,000 mg/l) and biochemical oxygen demand (BOD) (11,200-15,660 mg/l) and suspended solids (SS) (5,460-7,370 mg/l). It cannot be directly discharged into surface water bodies, due to its highly biodegradable nature. Herbal pharmaceutical wastewater has been treated by using vermifilter, which is an ecosystem consisting of biosoil with bacteria and earthworms producing vermicastings. In the present studies a cost-effective, eco-friendly and sustainable method has been applied for the treatment of herbal pharmaceutical wastewater using earthworms. Studies were carried out at different organic loadings, ranging between 0.8 and 3.2 kg COD/m(3)day at three different hydraulic loadings of 1, 2 and 4 days. Vermifilters packed with 1:1:1 ratio of soil, sand and vermicast as media matrix along with the twenty adult earthworms in each reactor was used for the experiments. Treated effluent was colour and odour free. Efficient COD/BOD removals in the range of 85.44%-94.48% and 89.77%-96.26% were obtained respectively at 2 days hydraulic retention time (HRT). Heavy metal removals were also observed and no sludge production problem was encountered, only nutrient rich vermicast from the filters were removed and analysed after the experiments. It showed higher manurial value than control in terms of available nitrogen, phosphorus and potassium (NPK) and were in the range of 178.75-278.75 Kg/hectare available nitrogen, 16.128-50.4 kg/hectare of available phosphorus and 19.3-28.6 kg/hectare of available potassium at maximum HRT and at different organic loadings. This paper discusses in detail the feasibility of vermifilters in herbal pharmaceutical wastewater treatment at different organic and hydraulic loadings.

Pretreatment of garden biomass using Fenton’s reagent: influence of Fe2+ and H2O2 concentrations on lignocellulose degradation

Garden biomass (GB) is defined as low density and heterogeneous waste fraction of garden rubbish like grass clippings, pruning, flowers, branches, weeds; roots. GB is generally different from other types of biomass. GB is mostly generated through maintenance of green areas. GB can be processed for bio energy production as it contains considerably good amount of cellulose and hemicellulose. However, pretreatment is necessary to delignify and facilitate disruption of cellulosic moiety. The aim of the present investigation was to pretreat GB using Fenton’s reagent and to study the influence of Fe2+ and H2O2 concentrations on degradation of lignin and cellulose. The data were statistically analyzed using ANOVA and numerical point prediction tool of MINITAB RELEASE 14 to optimize different process variables such as temperature, concentration of Fe2+ and H2O2. The results of the present investigation showed that Fenton’s reagent was effective on GB, however, concentration of Fe2+ and H2O2 play crucial role in determining the efficiency of pretreatment. An increase in H2O2 concentration in Fenton’s reagent significantly increased the rate of cellulose and lignin degradation in contrast to increasing concentration of Fe2+ ion which led to a decrease in lignocellulosic degradation.

Development of Microbial Consortia for the Effective Treatment of Complex Wastewater

The complex wastewater was characterized for physicochemical parameter. Five microbial species were isolated from different potential sources and their degradation potential was evaluated individually and in the form of consortia. Accordingly, lab studies were carried out in biological treatment system using aerobic microbial consortia along with individual microbial species in separate reactors. Temperature and pH of reaction tank was continuously monitored during study period. Other vital physicochemical parameters viz. COD, BOD, TSS and TDS were evaluated during 72 hours of study. The microbial consortia comprise of Pseudomonas spp., Actinomycetes spp., Bacillus spp., Streptomyces spp. and Staphylococcus spp. was able to trim down the physicochemical parameters of complex wastewater. The consortia demonstrated high COD and BOD reduction up to 90.17% and 94.02% respectively, compared to individual microbial species ranging from 42.11-59.76% for COD and 58.55-77.31% in case of BOD.