The Uses of Natural Gas
Why do we need natural gas?
Natural gas is used to produce electricity
In Trinidad and Tobago, a large percentage of the natural gas transported and sold by NGC is used for power generation, by power plants both in Trinidad and Tobago. Natural gas is used to run the turbines at these plants, and the turbines generate a continuous supply of electricity, every day of the year.
Other fossil fuels, like oil, coal or diesel, can be used to generate electricity, but they produce large quantities of greenhouse gases and other pollutants. Natural gas is comparatively clean-burning, and is better for the environment.
Natural gas is also one of the cheapest fuels, and in T&T its use is subsidised by the government, which means the government pays part of the cost. Because of this, we pay less for electricity in our homes and businesses than most other countries in the region.
Natural gas is used to make ammonia
Natural gas is a collection of different gases, all of which are comprised of molecules of carbon and hydrogen. (To learn more about the composition of natural gas, read What is Natural Gas.)
Ammonia is made up of nitrogen that is taken from the air, combined with the hydrogen present in the gas stream. It is a clear, colourless liquid with a strong odour.
Ammonia is produced in very large quantities in factories at the Point Lisas Industrial Estate in Couva. In fact, Trinidad is one of the largest exporters of ammonia in the world, from a single site. That’s pretty impressive, for such a small island!
This ammonia is used for industrial purposes as a cleaner, in the production of a wide range of chemicals, and as a fertiliser.
But ammonia is also a naturally occurring compound. It is found in the soil as a result of bacterial activity, and also when plant and animal matter decays. You also have quite a lot of ammonia in your body, as it is an essential building block for proteins and other substances.
Which brings us to:
Natural gas is used to make urea
Actually, to be more specific, AMMONIA is used to make urea. It is combined with liquid carbon dioxide at factories on the Point Lisas Industrial Estate, under pressure and high heat. As it cools, it solidifies into white grains.
Urea is sold as a fertiliser. You’ve probably seen it if you live in an agricultural area. In Trinidad we often simply call “salt”. Urea is also used to produce many other chemicals, including medicines, plastics, resins and glues.
Like ammonia, urea is produced naturally in your body. You can find it in human milk, sweat, bile and blood. It is the result of metabolism, and a lot of it is excreted in your urine.
Natural gas is used to make methanol
Remember, most of the natural gas stream is comprised of methanol, which is the lightest and least complex hydrocarbon molecule. Factories on the Point Lisas Industrial Estate use methane to produce methanol.
First, they create a synthetic gas made up of carbon monoxide and hydrogen gas by passing the methane over a catalyst (a substance that can stimulate a chemical reaction) under very high temperatures and pressure. The resulting gas is mixed with carbon dioxide and exposed to another catalyst, and methanol is formed.
Methanol is a clear liquid that is actually a form of alcohol, but unlike alcoholic beverages such as rum or wine, it is highly toxic and can blind or kill if ingested.
Liquid methanol is exported from Trinidad to other countries by ship. As with ammonia, we are among the largest exporters of methanol in the world, from a single site.
If you were to list the uses of methanol, that list would be as long as your arm. But a few of these are in the production of medicines; to make paint and adhesives; to produce plastic; as an antifreeze in cold climates; as a booster for gasoline; to make fabrics and clothing; and for making pesticides, solvents, and other industrial chemicals. Some vehicles even use methanol as a fuel!
Natural gas is used to make metals
No, the gas itself doesn’t become a metal, but it is used in the furnaces to produce very high heat to make important metals such as iron and steel.
To produce iron, iron ore that is mined from the ground is heated in a blast furnace with charcoal or coke (a substance made from coal) and limestone. Temperatures in this furnace can reach up to 1,600 degrees Celsius! The limestone and impurities in the iron ore combine to form slag, while the molten iron is allowed to flow out of the furnace.
This unrefined iron is known as pig iron. It is too brittle to be useful, so it must be further processed. It can further be refined in different ways:
- It can be melted and mixed with slag to create wrought iron, used in gates, fences and furniture
- It can be melted with scrap iron and other metals to make cast iron
- Or it can be further purified to form steel, which is very strong indeed
Not only are there companies on the Point Lisas Industrial Estate that produce iron and steel using natural gas for heat, but there are smaller companies that use these metals to create a variety of other industrial and household products.
Natural gas is an environmentally responsible vehicular fuel
Compressed natural gas, or CNG, is making a comeback in T&T. You’re probably too young to remember, but a few years ago it was introduced to the market. It’s a cheaper fuel, and burns more cleanly than gasoline or diesel.
But back then, filling your CNG tank took a long time, and very few gas stations had CNG fuelling pumps. The CNG tank also took up a lot of trunk space in your car. So in spite of the many advantages of this useful fuel, it wasn’t very popular.
But things have changed. CNG tanks take up much less space in cars, and some cars even come CNG-ready straight from the factory. Gas stations all over the country are installing new, faster pumps, so that filling up will be faster and easier. Many public transportation vehicles, such as buses, will soon be using CNG. The government is also offering tax incentives to people who convert to gasoline.
So it’s only a matter of time before the travelling public falls in love with CNG. As a matter of fact, most of NGC’s newest fleet of vehicles uses CNG. We love to lead by example.
Natural gas is used in air conditioning systems
Natural gas is used for cooking, baking and sterilising
Soft drink and juice manufacturers use it to heat their sterilisers for bottles and other containers.
Other companies use natural gas for
- Steam cleaning and heating in laundries
- Heating kilns to make clay products such as pots and deyas
- Heating plastics to shape them into pots, buckets and water containers
Natural gas is even converted to Liquefied Natural Gas (LNG) under high pressure and extremely low temperatures, and shipped to consumers in the USA and Europe.
Natural gas is very useful indeed!
We could go on and on about the many ways in which natural gas is used but you’ve already absorbed so much information!
As you go, just remember that natural gas is one of the cleanest, cheapest, most versatile and efficient fossil fuels. Very few of us live our lives untouched by it, or products that depend on it, and that’s why NGC works so hard to ensure safe, reliable and satisfactory delivery of this precious fuel to its consumers every day of the year.