Abstract:
Waste water treatment using aquatic plants is gradually gaining importance. The
aquatic treatment system consists of one or more slmllow ponds in which one or
more species of aquatic macrophytes are grown. Waterhyacinth is one of the most
promising aquatic plant which has been successfully used all over the world in
industrial waste water treatment. In this study an experimental investigation has
been carried out to find the effectiveness of water hyacinth in control of pollution
by textile liquid waste.
Tlds study focuses on the c1mracteristics of liquid waste of existing textile
industries in Bangladesh. In our country very small" efforts are made for tlze
treatment of industrial waste. Most of the existing industries dispose off liquid
waste having pollution indication parameters exceeding the respective
environmental quality standard. This study shows that the effluents from these
industries can be effectively treated by water hyacinth ponds as an alternate low
cost treatment method before discharge of raw liquid waste into a surface
waterbody.
In this study different experiments have been conducted to determine the
removal rate" of pollutants with giving importance to colour, turbidity,
suspended solids from textile liquid waste at different concentrations of waste
water and at different pH. Ignoring the effect of different types of water hyacinth
in the treatment of waste water, in this study plants having long and extensive
root system are used. Representative samples of Beximco Textile Industry were
collected and polluting parameters were analysed in the Environmental
Engineering laboratory of BUET. Water hyacinth was used to treat this liquid
waste at different concentrations in some plastic buckets. Samples from these
buckets were collected at regular interval and pollutant contents were
determined. This process was repeated- to determine the removal of pollutants by
water hyacinth at different pH of raw effluent.
This study reveals tlmt water hyacinth could be positively used in the treatment
of waste water. It has found that removal rate of pollutants by water hyacinth are
excellent if the waste water is diluted fifty percent. Test results also show that
removal rate of pollutants at pH 4.8 are much better thlm at pH 6.8 of the waste
water.
Treatment of textile liquid waste by coagulation and sedimentation process gives
a better understanding of the effectiveness of alum for removal of pollutant. An
attempt was made to remove pollutants from textile liquid waste by sludge
blanket and coal filter method.
