Sable Chemical has shelves plans to use coal gasification at its fertiliser plant in Zimbabwe.
The company hoped to use coal gasification as a solution to the energy intensive electrolysis process used to produce the hydrogen requires for the manufacture of ammonium nitrate.
However, the use of electrolysis in the process has come at a high cost to Sable.
The company is now looking to use coalbed methane (CBM) instead of coal gasification.
An unnamed Chinese company has since been engaged to carry out a feasibility study expected to lead to fundraising based on the CBM alternative.
Sable is Zimbabwe’s sole manufacturer of nitrogenous fertilisers.
CBM gas contains hydrocarbons from which the fertiliser feedstock can be derived through a simpler and cleaner process than electrolysis.
Sable Chemical CEO, Jack Murehwa, confirmed in an email that the company would no longer pursue coal gasification, as CBM was a more viable way of getting the hydrogen.
Coal gasification is the process of producing syngas, a mixture of gases consisting primarily of methane carbon monoxide, hydrogen, carbon dioxide and water vapour, from coal and water, air and/or oxygen.
"While Sable has been pursuing coal as the feedstock towards change of technology, a more practical and convenient feedstock, coal bed methane, has just been confirmed to be a more pragmatic option,” Murehwa said.
"In that light, work is currently going on with a Chinese engineering company to produce a feasibility study, which will lead straight into fundraising for the project based on coal bed methane," Murehwa added.
The Sable Chemical CEO said the company was getting enough electricity, however, amid revelations that the company currently requires an average of 80 MW.
Industry sources said the Kwekwe based company has accrued a US$123 million power bill, as it struggled to cope with its huge appetite for power. However, Murehwa dismissed the claims as "untrue".
The huge power consumption nature of the electrolysis plant has been at the heart of the perennial viability challenges the firm has faced in recent years, prompting TA Holdings to write off its investment in Sable.
Sable Chemical Deputy Chairman, Misheck Kachere said CBM was a more clear gas and simpler way of getting hydrogen from hydrocarbons, which are extracted from the underlying seams of coal.
He said the process produces less material that pollutes the environment, such as hazardous gases and ash, which needs careful disposal.
Zimbabwe has, in recent years discovered huge reserves of CBM gas in Matabeleland North Province, and the resource is largely believed to be in such abundance as to exceed the entire reserves in the SADC region. SADC gas resources amount to 420 billion m3, while it is estimated that the Hwange/Lupane basins have about 765 billion m3 of sulfur-free CBM.
Edited from various sources by Sam Dodson
Read the article online at: https://www.worldcoal.com/cbm/16122014/sable-opts-for-coalbed-methane-over-coal-gasification-cbm172/