CONSERVATION OF WET ALKALINE SOIL BY BIOLOGICAL TREATMENT OF ALKALINE TEXTILE INDUSTRIAL WASTEWATER

In the endeavor of making the environment pollution–free, some industries are enforced to treat their wastewater before its release in the environment. Wastewaters emanated from industries may be toxic, hot, highly acidic or alkaline, colored etc. where general micro-flora cannot exist. Textile wastewater is such type of wastewater which is highly alkaline (pH-12) and thus it is difficult to treat because general micro-flora cannot survive in such adverse conditions. Present work deals with biological treatment of industrial wastewater, which causes the high alkalinity in the soil of industrial premises (Punjab, India) where wastewater is released.

For the isolation, soil sample of high alkalinity was taken from the textile industrial premises. Different concentrations of soil extract mixed with alkaline bacillus medium were used as media to entrap the desired micro flora after enriching the soil in soil extract for two days at 120rpm/320C. On the basis of high pH tolerance (12.0), a gram positive and aerobic bacterium was screened which is identified as Kurthia sp. Alkaline bacillus medium (ABM) was selected as the suitable medium and maximum growth of one-liter culture could be achieved in ten hours. For the neutralization of textile wastewater, ten hours grown culture was centrifuged and the pellet was added to alkaline (pH 12.0) textile wastewater. In order to check the secretion of extra cellular amylase, a smear of Kurthia sp. was made in the center of the experimental starch agar media plates and incubated for 48 hours at 370C. After getting the visible growth of bacteria, plates were flooded with Lugols Iodine followed by destaining with distill water.

The isolated bacterium was identified as Kurthia sp., which is capable to neutralize the alkaline wastewater. In a trial to neutralize the alkaline industrial wastewater, this bacterium has been found capable to neutralize textile industrial wastewater from pH 12.0 to pH 7.5 within two hours. A clear zone was obtained in the experimental starch agar plates when flooded with Lugols Iodine, which indicates the capability of this bacterium for starch degradation. This kind of promising biotechnological processes may be of high importance in conserving the alkaline soil.