Sindh preparing policy to produce gas from Thar coal
The Sindh energy department will prepare a draft policy for production of liquid gas from coal, said Asif Mangi, Deputy Director Sindh Coal Authority (SCA), in an interview with WealthPK.
This decision was made in a high-level meeting of Sindh Coal Authority chaired by Sindh Energy and Planning Minister Syed Nasir Hussain Shah recently.
SCA consultant Dr Farid A Malik told WealthPK that Thar coal was declared a subject for gasification in the international laboratory of South Africa. He said the meeting was also informed that gas production from coal could save about 500 million dollars in foreign exchange annually.
In terms of gas import, an energy system from Thar’s 175 billion tons of coal reserves could reduce the energy import bill by 50 percent. It was decided that Nasir Shah would personally contact the federal energy minister in connection with coal gasification.
Coal gasification is a process that converts solid coal into a combustible gas, composed primarily of carbon monoxide and hydrogen, by adding an oxidizing agent (air, oxy-gen, water vapor). Coal gasification offers a practical means of utilizing coal for meeting the stringent environmental control requirement. In the gasification process, the sulfur present in the coal is converted to hydrogen sulfide (H2S) and minor amounts of carbonyl sulfide (COS).
These sulfur compounds can be easily and economically removed from the gas streams by a wide variety of commercially available processes (i.e. acid gas removal systems).
The SCA conducted a study some time ago to evaluate the viability of Thar coal for conversion to gas, liquid and urea. Samples of coal were shipped to a South African laboratory for testing and evaluation. The study revealed that Thar coal had high tar yields of 20 percent (air dried basis) and high CO2 reactivity, which were typical of lignite coal and suitable for gasification.
The report also said that the sulfur content of Thar coal was higher than expected, but it was not a concern from the gasification point of view. The ash flow temperatures are around 1320-1340 degrees Celsius. The studied sample was found to show relatively higher char–CO2 gasification reactivity compared to bituminous coals. The study suggested that Thar coal is viable for conversion into gas, liquid and urea.