Abstract:
The wastewater from dyes and their intermediate manufacturing industry causes
serious impact on natural water bodies and land surfaces in the surrounding area. The
dye wastewater is treated by using many effective physical, chemical or biological
techniques in the world. High values of COD and BOD, presence of particulate matter
and sediments that give intense color intensity and turbidity in the effluents are some
factors leading into the depletion of DO. There are five dyeing cottage industries in
operation at Maruthamunai and above mentioned problems are noticed to be occurring
in that area. In this part of study, we used different materials with the objective to select
some efficient ones to control the COD and the colour intensity of the wastewater by
adsorption from one of those dyeing industries. Dye wastewater parameters, such as
pH, EC, colour intensity, and COD were analysed by using HACH multi-parameter,
pH and conductivity meter, spectrophotometer (HACH, DR 2010) and titrimetric
methods, respectively before and after the treatments with the different materials.
Oxidizing properties of H2O2 and adsorption properties of charcoal were used for
treating dye wastewater in our work, in addition to different materials such as coal
(from fire wood) paddy husk, saw dust, dry peel of ariconut, nirmali (S. potatorum)
seeds, etc used. These results indicated that H2O2 oxidizes both organic and inorganic
pollutants which contribute to COD. Adsorption was an effective process for
decolourization of textile dyes. Although different materials were tried, activated
carbon was the most effective adsorbent due to its high surface area. Using these two
substances H2O2 and activated C, we were able to reduce the COD (60.2%.and 9.5%,
respectively), pH (3.61%, and 2.61% respectively), EC (22.2%, and 5.3% respectively)
and colour (88.33%, and 82.58% respectively) of dye wastewater. The results showed
that the adsorption process using activated carbon insured a good degree of color
reduction and chemical oxidation using H2O2 as oxidant allows the effective control of
organic load, offensive odor and foaminess in domestic wastewater.
