Solid and effluent waste streams which cannot be avoided through cleaner production technologies, require treatment and mitigation. Opportunities also exist to consider waste as renewable resource, with potential for sale-able by-products recovery, e.g. high quality calcium sulphate, calcium carbonate, magnesium carbonate, sulphur and valuable metals Technology solutions for waste treatment, product recovery and pollution mitigation focus largely on support to industry and municipalities, supporting the objectives of sustainable development and industrial ecology.
Through directed research and technology intervention, the CSIR aims to support those organisations tasked with the improvement of effluent water quality for the benefit of society. The cost-effective production of high quality effluent from various waste streams is the group's priority and in achieving this objective, it will be making a meaningful and sustainable contribution to the quality of life, including that of future generations. Some utilities responsible for waste treatment are moving away from regulatory compliance towards increased economic incentives, in recognising the value of waste and wastewater as a resource. This includes the recovery of nutrients, metals and other chemicals as part of the wastewater treatment process. Further beneficiation of recovered by-products to enhance waste utilisation is included in the group’s research and development focus. The CSIR recognises that to ensure technology uptake and impact in the market place, the technology needs to be assessed in terms of sustainability and financial viability, from early conceptualisation through to implementation. Sustainability assessment methods and technology comparisons will form an integral part of pollution and waste treatment technology development.
Acidic and decant water:
Research conducted in our chemical and biological laboratories places NRE in a strong position with respect to research and technology development in the treatment of acidic mine water. Suspended material, both organic and inorganic, found in industrial and mining wastewater can be removed via conventional filtration technology, however, the dissolved solids (including nutrients) cause increasing salinity and metal ions concentrations resulting in environmental pollution. Viable solutions are recommended to treat the acidic water that is currently discharged from mines or used and recycled in the processing plants. The CSIR’s treatment process (e.g. ABC, limestone/lime neutralization) has been implemented in recent years at several industrial plants and is now recognised worldwide by leading engineering firms as the best practice for water treatment in various applications.
Municipal wastewater treatment:
Existing wastewater treatment facilities in South Africa are rapidly running out of capacity mainly due to urbanisation and therefore, expertise to deal with the steadily increasing demands are required.. The CSIR’s research into municipal wastewater treatment aims to address pre-treatment of raw wastewater (so as to increase downstream and secondary treatment capacity); improved and optimised operation of existing (and sometimes old) treatment technologies; assisting in the implementation of best available new technologies, not yet established in South Africa.
Laboratories and equipment
In order to conduct research in waste and wastewater treatment, the Waste Treatment and Utilisation (WT&U) research group utilises several well equipped modern laboratories, such as the chemical and biological process laboratories, analytical laboratory and pilot plant laboratory for on-site pilot plant operations.