South African cement group Pretoria Portland Cement (PPC) is to undertake a major project to reduce dust emissions at its De Hoek factory in the Western Cape. The cost of the project is about R70-million and will be completed by 2011.
This is in line with the company’s commitment to improve the environment around the communities in which it operates countrywide and adhere to international environmental best practices.
Even if the current dust emission levels are not regarded as a health threat, reduced emissions will further improve the air quality for both employees and residents and ensure that the company complies with the new legislation.
The South African Department of Environ-mental Affairs and Tourism believes that the new legislation to deal with air pollution is an indication of government’s determination to enforce citizens’ constitutional right to a clean and safe environment.
The Cabinet recently approved the national environmental management’s Air Quality Bill for public comment on how air pollution, greenhouse gases and ozone-reducing substances could be controlled to ensure that the air quality did not result in ill health.
The bill sets standards that will define air quality and, once determined, provision is made for the means by which these standards may be achieved and maintained.
PPC operates two production facilities in the Western Cape, one at De Hoek, near Picketberg, and the other at Riebeeck West. De Hoek, the larger of the two facilities, produces about 800 000 t/y of cement for the Western Cape market from two rotary cement kilns.
The kilns are currently fitted with electrostatic precipitators, older technology, which uses electric power to separate dust particles from the kiln exhaust gas, enabling cement plants to operate with low dust emissions.
PPC COO Dr Orrie Fenn says that the precipitators will be replaced with state-of-the-art bag-filter technology, where the kiln gas is dedusted in a better way, similar to a very large vacuum cleaner.
Modern bag filters are much more efficient at removing dust from gas, with the dust concentration in the cleaned gas seldom exceeding 20 mg/m3.
“This is well below the level of 50 mg/m3 required by international and European standards and will comfortably meet the expected requirements of the new South African Air Quality Act,” says Fenn.
The engineering design for the new bag filters is currently under way. The expected lead time for delivery of the equipment is one year and it is planned to have the new dedusting systems installed and fully operational by 2011. Until then, PPC will increase the efficiency of the current dedusting equipment to ensure that the lowest possible emission levels are maintained.
Fenn states, “PPC is committed to working closely with the authorities and communities in all the areas where we operate to ensure that environmental impacts from ongoing operations are kept to a minimum. In addition, we seek to actively improve the lives of our employees and local communities by investing in upliftment projects and education.”
The De Hoek project follows similar successful projects carried out at PPC’s lime manu- facturing operation in the Northern Cape, where R20-million was spent on bag filter technology, and at PPC’s Slurry, Jupiter, Hercules and Port Elizabeth cement plants, where over R40-million has been spent to date on improving environmental conditions.