Research finds Thar coal suits power plants.
Fuel Research Centre of PCSIR, Karachi has found that Thar Coal is suitable as a solid fuel in its natural form for coal fired power plants and boiler furnaces in industry. The research has been done by Anila Sarwar, a PhD scholar, under the supervision of Prof Dr M Nasiruddin Khan of Karachi University's Chemistry Department.
The study focuses on quality and reactivity assessment of Block V of Thar. Its primary objective was to access quality of coal and set up a database for measuring its reactivity to understand its suitability for designing and setting up commercial plants.
The research titled 'Kinetic studies of pyrolysis and combustion of Thar coal by thermo gravimetry and chemo metric data analysis' has been published in the Journal of Thermal Analysis and Calorimetry.
The most important finding of the study is ranking of coal as lignite to sub-bituminous under standard classification of coal by American Standard and Testing Materials (ASTM). Sub-bituminous is a type of coal used as fuel for steam for generating electricity.
Dr Nasiruddin Khan adds that Thar coal has low sulfur content and ash making it better than other coals as it helps reduce repair and maintenance costs significantly. This is an attractive economical aspect of Thar coal.
The study also showed that Thar coal can be converted into gas and liquid fuel easily with a good yield of substitutes for oil or natural gas.
Thar coal is suitable as solid fuel in its natural form, needs less energy for igniting it and its combustion is safe for environment as it produces less ash and poisonous gases, says the research.
Most samples studied by the research team were found to have low ash (less than 10%) and low sulfur (less than 2%). Combustion of this coal is considered safe for environment as it produces very little ash and low amount of SOx (oxides of sulfur) gases.
Ignition temperature (the temperature required to start ignition) of the coal varied from 315AdegC to 450AdegC. Activation energy (Ea) for pyrolysis and combustion reactions was calculated as 35.50 and 34.27 kJ/mol, respectively.
It is significantly less than the Ea of foreign coals. Low activation energy values of Thar coal categorise it as a reactive coal and can undergo pyrolysis and combustion reactions easily, says the research.
In brief, Thar has better coal than Lakhra which has high sulfur content (between 1.2 and 14.8%), and high ash (between 4.3 and 49). High ash and high sulfur content in coal damage plants, which then require expensive maintenance.
Thar coal was discovered in 1991 and Geological Survey of Pakistan developed four blocks between 1994 and 2000. This research is the first comprehensive study on its characters. There is no data describing it as low quality lignite.
There is a strong need to learn from past mistakes and explore new reserves that have the potential to be used as raw material, says Dr. Khan. Characterisation and combustion study of a new coal reserve is the first step towards its proper utilisation.
|Printer friendly Cite/link Email Feedback|
|Publication:||Pakistan Engineering Review|
|Date:||Jun 15, 2013|
|Previous Article:||Engineering design completed Const'n of Bunji soon.|
|Next Article:||Why is Lakhra off?|