Performance evaluation of vinasse treatment plant integrated with physico-chemical methods.

With an objective to assess environmental management criteria of a vinasse treatment plant (VTP) and to evaluate the critical environmental parameters, a study was undertaken in a multi-product (packaged apple juice, distillery, brewery, packaged drinking water) brewery-cum-distillery unit. The facility with a volumetric loading rate of 11-15 kg COD m(-3).day, 3.6-4.5 h hydraulic retention time and 20 g l(-1) VSS had a scientifically managed technically sound effluent treatment system. While the water quality parameters were found within the acceptable limits, there was 99.07% reduction in BOD, from 43140.0 to 398.0 mg l(-1) and 98.61% reduction in COD from 98003.0 to 1357.0 mg l(-1). There was appreciable improvement in mixed liquor suspended solids (MLSS), mixed liquorvolatile suspended solids (MLVSS) and sludge volume index (SVI). A striking feature was the integrated aerobic-anaerobic highly efficient Up-flow Anaerobic Sludge Blanket (UASB) treatment for biodegradation and energy production that reduced energy and space needs, producing utilisable end-products and net savings on the operational cost. The end-point waste management included terminal products such as fertile sludge, cattle feed supplement, recyclable water and biogas. Vast lagoons with combined aerobic-anaerobic approaches, biogasification unit, sludge recovery, remediated irrigable water were the notable attributes.

An investigation into the prospects of arsenic(v) removal from contaminated groundwater using untreated bauxite ore.

Steady-state experiments were conducted on arsenic (V) removal from contaminated groundwater using two different grades of bauxite ore. The materials considered were refractory grade bauxite (RB) with high alumina and low iron content and feed bauxite (FB) with moderate alumina and high iron content. Adsorption studies were carried out for different parameters such as pH, adsorbent dosage, As(V) concentration and reaction time to establish optimum conditions. RB was found to be the better adsorbent compared to FB with a maximum As(V) adsorption capacity of 1.49 mg As(V)/g compared to 1.26 mg As(V)/g of FB. Both the adsorbents showed similar type of behavior with varying magnitude. As(V) adsorption was independent of the ionic strength suggesting an inner-sphere surface complexion mechanism. The kinetics of the As(V) adsorption could be best explained by pseudo-second-order rate equation. The adsorption was found strongly pH dependent, with maximum adsorption over a wide range of pH approximately 4.0 to 7.5. The column study results showed that at a adsorbent bed depth of 30 cm and feed flow rate of 50 ml/h, the RB was capable of treating 256 bed volumes of As(V) contaminated water (Co=1.79 mg/L) before breakthrough (Ce=0.01 mg/L).