The article discusses how to make coal gas using a special process called Shell coal gasification. They compare this method to another one called Texaco water coal slurry gasification. Shell coal gasification can work with more kinds of coal and uses heat better. It also lasts longer and has better controls. The team suggests ways to make Shell coal gasification even better in areas like removing waste and treating water. The research shows that Shell coal gasification is more flexible and efficient than Texaco gasification.