Performance studies of ECORITE PAC-2010 as a coagulant in water treatment.

This paper describes the performance evaluation studies of ECORITE PAC-2010 of M/s Shriram Consolidated Limited (DSCL) as a coagulant. It was observed that ECORITE PAC-2010 acts as a good coagulant over a wide range of turbidity and produces larger and more rapidly settleable flocs than the alum. The residual aluminium is less in ECORITE PAC-2010 treated water than that in alum treated water. The sludge volume generated by ECORITE PAC-2010 is less than that generated by alum for attaining the same quality of settled water from turbid raw water.

Removal of basic dyes from aqueous medium using a novel polymer: Jalshakti.

Studies were carried out to remove basic dyes such as safranine T, methylene blue, crystal violet, light green, brilliant milling violet and patent blue VS from their aqueous solutions using biodegradable polymeric absorbent material, viz., Jalshakti (JS). Results showed that 93% safranine T, 98% methylene blue and 84% crystal violet were adsorbed on JS relative to their initial concentration (10 mg L(-1)). The optimum pH was found to be 6.0+/-0.5 and smaller size of particle of JS resulted better adsorptive removal of the dyes. IR spectroscopic and potassium ion release studies revealed that basic dyes were selectively removed through adsorption-ion-exchange mechanism involving carboxylic groups and K+ ions of JS.

Polychlorinated biphenyls in compost amended soil of a landfill site.

The soil receives enormous quantities of pesticides and PCBs as a waste product each year due to their wide application. The degradation and eventual fate of these chemicals in the soil largely determine ultimate environmental impact. A survey of an abandoned landfill site has been conducted in a fast developing industrial city Nagpur (India) to assess the degree of environmental contamination with PCBs. The purpose was to determine if any of the mixture of PCBs, Aroclor 1254 and Aroclor 1260 are retained in the compost amended soil of the site despite atmospheric losses possible due the peak summer (100-117 degrees F) in the city. The accuracy and precision for Aroclor 1254 and Aroclor 1260 determinations in the soil samples have been calculated as 76.5 and +/- 0.92 and 83.3 and +/- 1.13 respectively. The samples analysis showed the presence of Aroclor 1254 and Aroclor 1254 and Aroclor 1260 up to the levels of 0.55 and 0.80 mg/g respectively. The maximum total PCBs on dry weight basis are found as 1.2 mg/g.

Laboratory and field assessment of arsenic testing field kits in Bangladesh and West Bengal, India.

High concentrations of arsenic in ground waters in West Bengal and Bangladesh have become a major cause for concern in recent years. Given the enormity and the severity of the problem of arsenic poisoning, a task of evaluating the commercially available arsenic detection field kits for their capabilities was undertaken. In the light of the findings, generic specifications were recommended which could form the basis for indigenous manufacture of these kits in the arsenic affected countries. This article presents the results of the laboratory and field evaluation conducted in Bangladesh and West Bengal of five arsenic testing field kits. The salient features of the kits, their merits and limitations have been brought out. Based on the criteria of kit design, quality of chemicals used, colour comparator charts, detection range, time required for analysis, cost etc., a comparative ranking of the kits has been made to facilitate the choice of the kit to meet specific requirements.