Process Waste Water Treatment Plant
BASF is the world’s leading chemical company which offers its customers intelligent system solutions and sophisticated products. The BASF group has an African footprint and has been active on the continent for close to 90 years. Its headquarters are in Germany and the key Industries involved with this company are construction, textiles, agriculture, automotive and the health care and plastics sectors. From 1958, the BASF Group Company Wintershall has be producing oil onshore in Libya and it is also involved in the offshore oilfield. Its production facilities for emission catalysts, construction chemicals, coil coatings, dispersions and polyurethane plastics are based in South Africa.
The agricultural division of BASF had been having a problem with the quality of the water produced by its processes. The water quality was not meeting the municipal discharge specifications, therefore they contacted Watericon to seek a solution. When the water was tested it was found to contain Manganese, Fluoride, and Iron, there was also a problem with the colour of the water, turbidity as well as COD levels.
In order to treat the water, the Watericon engineers designed a Wastewater Treatment Plant consisting of chemical pre-treatment, followed by primary slow dual-media and secondary slow activated carbon filtration complete with chemical dosing for the addition of chemicals at certain pre-determined stages of the treatment process.
The WWTP consisted of the following:
- Raw water storage and pumping
- Reaction vessels
- Chemical dosing system
A waste water treatment plant was designed. The process begins at the raw water collection tank, the pH is then corrected followed by floc addition as well as floc aid to improve the reaction. To allow sufficient retention time, a settling process is next in-line, followed by filtration to remove the suspended solids as well as other constituents in the water. For the growth control of micro-organisms, a chemical is dosed and then the water is sent to the filtered water tank. For the removal of fluorides in the water, absorption columns are incorporated and water leaving the columns will be within the SANS discharge specifications.
Results and discussions
Please note that the pH units have been multiplied by a factor of 100 for the purpose of variation in the scale. To get the actual value of the pH, one should divide by a factor of 100. Graph 1.1 above informs us that there is a decline in the major parameters such as the level of COD, TSS and Colour as well as conductivity. The pH experienced an increase because the raw water sample contained a low pH but after pH correction it was restored to a neutral pH that is within the discharge specification.
For the turbidity, we achieved removal of about 98.4 %, for the COD, the achieved removal was 80.2 %. Removal efficiencies of 96.4 and 93.7 % were also found for the TSS and the colour respectively. These results prove that the processes designed by the watericon engineers bring excellent and sustainable results.