BENEFICIATION
RDF plant situated at the Interwaste Germiston depot .
Interwaste the RDF is important to guarantee a product consistent in quality .
Secondly , the chlorine content of the RDF could have an effect on the process . If the chlorine content exceeds 1.5 %, it is at risk of evaporation and condensing of chlorine gas in the system , which over time could weaken the refractory bricks in the cement kiln .
Chlorine content may also affect the quality of the cement , or intensify corrosion of steel rebar in concrete structures . From a production perspective , producers need to strike a balance between the amount of chlorine and Sulphur in the process .
Long-term financial gains
Despite standard new technology challenges , the economic and environmental benefits of using waste derived alterntive fuels to
replace fossil fuels in cement plants are vast . Considering global climate change discourse and how fast Europe is moving , it is not a case of ‘ if ’, but rather ‘ when ’ to convert to cleaner sources of fuel .
Financially , the impact is two-fold : firstly , RDF minimises the direct cost of energy through a cheaper fuel source . Secondly , carbon tax legislation could provide massive economic gains .
“ Using a fuel that is less than the base price for coal automatically reduces the direct cost of energy . If the South African government passes the carbon tax bill , cement producers will also be able to claim back for lower emissions . For every tonne of coal that you substitute with RDF , producers reduce their CO 2 emissions by 1.5 tonnes . We essentially provide our customers with a solution to reduce operational expenses , while acting responsibly towards the environment ,” Young concludes .
Pressure to cut emissions is mounting both globally and locally , and the RDF facility presents an alternative for South African cement producers to scrutinise their current processes and adopt greener operational practice .
As with any innovation , supply and demand speaks volumes . In this case , quite literally . To produce RDF at economically viable quantities , the plant requires high volumes of waste set off against stable demand from cement kilns .
External factors such as carbon tax and landfill legislation , coupled with cement producers ’ internal willingness to drive plant conversions , will dictate the success of RDF uptake in South Africa . n
QUARRY SA | JANUARY 2017 _ 25