South Africa’s first vertical shaft brick kiln (VSBK), which boasts material energy savings, is being constructed at clay brick manufacturer Langkloof Bricks, in the Eastern Cape.
The technology transfer project is occurring in partnership with the Swiss Agency for Development and Coopera- tion (SDC), together with its implementation partners, Swisscontact and Skat.
The kiln, being built by Langkloof Bricks at its factory located between Humansdorp and Jeffreys Bay, will be complete and commissioned in August this year.
It has the biggest internal shaft dimension yet built, with a cluster of six shafts being built on a single raft foundation.
The open-source technology kiln, which was originally used in Asia, is an environment-friendly project that reportedly satisfies all the criteria of sustainable development and complies with government’s call for a 33% reduction in South Africa’s carbon footprint by 2020.
Namakwa Stene owner and VSBK project initiator Kevin Fruin explains that the VSBK offers a solution that will reduce coal consumption by up to 50% and improve the energy efficiency of the brick-firing process as well as lead to a 50% reduction in carbon dioxide (CO2) emissions.
The VSBK process cuts the time of brick firing from eight weeks using the clamp method to just 24 hours. It also reduces particle matter, which causes most of the respiratory illnesses in the labour force, by 90%.
“The VSBK offers safer and healthier working conditions, as workers are not exposed to the elements because of the roof over the top of the kiln. This will result in improved labour efficiency. In addition, the technology for the VSBK requires specialist skills, which will increase worker knowledge,” he says.
Fruin says that the macroeconomic benefits are also clear and in line with government’s job creation plan for the future.
“Continuing as we are today does not create additional employment, whereas making the investment in VSBK will result in 930 000 worker-days created during construction of the shafts,” he says.
The SDC has committed to the Clean Development Mechanism registration of the project, which hopes to result in 700 000 potential certified emission reduction credits, trans- lating into R960-million in foreign capital inflow over a ten-year period.
Fruin says that the target for phase one is to have 180 shafts up and running in South Africa by the end of 2013, which will result in a CO2 saving of about 150 000 t/y.
The final target is to have VSBKs firing 50% of the bricks produced in South Africa, which will mean a CO2 saving of 1,305-million tons a year.
Founded in China and improved in India, the VSBK is a continuous process where the bricks are fed in from the top and travel down the shaft through a central firing zone.
A total of 12 to 13 batches for each shaft, with 475 unfired bricks per batch, will fill a shaft and be hydraulically lowered from the top of the VSBK through the firing zone every two hours.
The foundation for this 12-m-high VSBK contains 105 m3 of concrete and 25 t of steel and the shaft will take about 220 000 normal bricks and 30 000 refractory bricks to construct.
All brickmakers in South Africa use some form of fossil fuel and account for 1,5% of South Africa’s coal consumption.
The VSBK will allow brickmakers to experi- ment with different fuel types more efficiently than clamp operations.
Langkloof Bricks executive director Nico Blake says that clay bricks are the best walling material option for the lowest life-cycle energy costing of any building material for the South African climate.
“The VSBK will allow us to continue making high-quality clay bricks through green technology,” he says.
Clay brick makers are under a lot of pressure in the marketplace, not only because of the economy but also because of alternative building mechanisms as well as tightening legislation.
For the first time, clamp operations have emission targets that need to be met and maintained, and need to monitor the amount and quality of coal used. The monitoring requirements will only increase over time.
The Air Quality Act regulations will become stricter over time and it will become increasingly difficult to report on and monitor clamp operations.
“The building industry, in general, also has a moral obligation to reduce its greenhouse-gas emissions and reduce its energy consumption. With coal being a finite resource and [given] the reality of global warming, this is something we need to implement. The VSBK is contributing to the brick sector’s to becoming much more environmental friendly,” says Fruin.
An issue that baffles Fruin, however, is the lack of local government cooperation in the project.
In achieving the target of 50% of bricks manufactured using the VSBK method, based on the production of five-billion bricks a year, 1 550 shafts will be required and R700-million in capital.
The SDC and investors have funded the project development and technology transfer so far, while the single entrepreneur has paid for the construction of the plant.
“The South African government up to now has acknowledged the benefits of the technology but has failed so far to provide clear support and incentives for its promotion through the green development funds,” says Fruin.