Cement firm in Mombasa goes for waste tyres and bag filters to reduce pollution

Bamburi Cement Production Superintendent Alfred Sieur (left) explain to journalists how cement is produced. [PHOTO: GIDEON MAUNDU/STANDARD].

MOMBASA: Bamburi Cement has adopted the use of waste tyres as a source of energy instead of coal in its efforts to reduce air pollution.

The firm has also installed larger bag fillers that will suck the dust emitted by the factory, thus greatly reducing pollution.

Ordinarily, cement is produced by using ultra-high heat to burn up raw materials to form clinker, the essentialcomponent.

“We import coal worth billions of shillings to burn raw materials in the process of cement manufacturing,” says Peter Gibendi, the plant manager at Bamburi Cement Factory in Mombasa.

But Bamburi has since switched to burning waste tyres as a source of energy instead of relying on the expensive coal. “With this, we were able to rid the environment of used tyres, while reducing – albeit to a small extent – the amount of money we spend on coal,” says Gibendi.

The tyre waste management is vital in eliminating open tyre burning that causes air pollution.

According to Gibendi, the Bamburi Cement kiln is the only facility approved by the National Environment Management Authority (Nema) to burn tyres in Kenya.

The factory also incurs the cost of energy used for trapping dust, a process which uses electricity powered filters. The Bamburi plant houses two operating lines, one which emits 10mg per m3 (way blow the international standard of 50mg per m3).

“The company invested in a bag filter, the best filtering technology, at the cost of Sh500 million, which has brought good results. The other line emits 110mg/m3, but still this is not visible pollution,” he pointed out.

Over the years, Bamburi has been bombarded by complaints from local residents, especially in Mwembe-Legeza, who complained about too much dust being emitted by the cement factory.

“The factory emits too much dust. We breathe this dust and it causes a lot of health problems. We have complained about it but no authorities have ever cared to find a solution to this,” Amina Chanzu, an old resident of Mwembe-Tayari in Bamburi, said.

Gibendi admitted that two years ago, dust pollution was a real problem.

However, he says with recent measures that saw the installation of a bag filter, dust pollution has been tamed to a large extent and what the factory emits now is within recommended international levels.

The use of tyres to burn cement has come with other benefits to the locals. The factory buys waste tyres from small-scale collectors and safely burns them as the cement is manufactured.

Coal, a fossil fuel, emits greenhouse gases when burnt and therefore has long-term effects on global warming.

Waste tyres, on the other hand, are burnt completely to the point that “very little if anything goes back into the environment”.

The complaints about dust continue, though. But Gibendi says the company has done what it can to ensure as little dust as possible is emitted: “Our aim is to bring dust emission to almost zero.”