Currently, there is a significant concentration of organic materials in watercourses and
/ or water reservoirs that receive domestic hazards and non-permitted industrial
effluents, which suffer prolonged drought damage and what are the natural conditions
caused by natural chemicals. The consequences can be the eutrophication of water
bodies, with the occurrence of blooms, which lead to problems such as taste and odor,
increased formation of unwanted decoration by-products, interferences in the water
treatment process, increased consumption of chemicals, in addition to corrosion of the
supply system units. Most water treatment systems, including those with full cycle
technology, without removing organic materials. One of the alternatives used in ETAs
to remove organic material is adsorption on pulverized activated carbon (CAP), a
practice that is easy to install in existing ETAs. The implantation of an adsorption unit
prior to the rapid mixing and the use or not of the pre-oxidation, should be studied
before the installation of adsorption processes in WTPs, since longer contact times
and pre-oxidation conditions, can enhance the adsorption with reduction in both coal
consumption and sludge generation, in addition to ensuring greater operational safety
of the system by removing organics compounds and providing quality treated water. In
this context, the present work aimed to investigate the influence of the contact time,
dosage and type of pulverized activated carbon on the efficiency of the adsorption of
organic matter in raw water submitted to the water treatment process in full cycle under
conditions with and without the pre-oxidation of water. The evaluation was carried out
using 5 types of CAPs of mineral, vegetable and animal origin. CAPs of plant origin
had an influence on contact time and dosage in the removal of organic matter,
measured in total organic carbon, that is, greater dosage and contact times brought
better results. Dosages of 30 mg/L and contact time of 25 minutes obtained the best
results, reaching removal efficiencies in the order of 90% and TOC concentration
below 3,0 mg/L. Pre-oxidation with chlorine did not prove to be advantageous in
removing organic matter, and it was evident that the guarantee of the best cost-benefit
in removing organic matter with the use of activated carbon and pre-oxidation with
chlorine, requires testing preliminary.
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