By Sonny Atumah
The reduction of greenhouse gas emissions has become a real issue globally. Many believe that environmental wisdom begins with the fear of greenhouse effect.
The greenhouse effect or global warming is an environmental matter that deals with the potential for global climate change due to increased levels of atmospheric greenhouse gases, according to the Intergovernmental Panel on Climate Change, IPCC.
The greenhouse gases include water vapor, carbon dioxide, methane, nitrogen oxides, and some engineered chemicals such as chlorofluorocarbons. Experts say while most of these gases occur in the atmosphere naturally, levels have been increasing due to the widespread burning of fossil fuels as human populations increase. Fossil fuels include coal, oil and natural gas.
Global appeals have been for abandonment of fossil fuels such as coal and oil in the name of global warming and climate change.
The focus of environmental programmes in countries is the alluring switch to natural gas. Natural gas is a mixture of combustible hydrocarbon gases mostly methane and ethane, found trapped in the pore spaces of some sedimentary rocks, often along with petroleum deposits. The different variations of natural gas include shale gas, deep natural gas, tight gas, methane hydrates and coal bed methane. There are two types of natural gas, the sweet and the sour.
Sweet gas is natural gas that doesn’t contain significant amount of hydrogen sulfide. Sweet gas is preferable because it does not contain much contaminant. In its purest form it can be used with very little refining. Sour gas is natural gas that contains significant amounts of acidic gases such as hydrogen sulfide and carbon dioxide, CO2. Hydrogen sulfide and carbon dioxide corrode piping during gas production and transportation. High concentrations decrease the amount of energy yielded when burning the gas.
Renown agencies attest to the fact that natural gas can be used in the transportation sector to cut down high levels of pollution from gasoline and diesel-powered cars, trucks and buses. Natural gas provides an efficient, competitively priced fuel for the generation of electricity. The increased use of natural gas allows for the improvement in the emissions profile of the electric generation industry. The use of natural gas to power both industrial boilers and processes significantly improves the emissions profiles for these sectors.
The combustion of natural gas emits almost 30 percent less carbon dioxide than oil, and just under 45 percent less carbon dioxide than coal. But one issue that has arisen with respect to natural gas and the greenhouse effect is the fact that methane, the principle component of natural gas, is itself a potent greenhouse gas. Methane has an ability to trap heat almost 21 times more effectively than carbon dioxide. Experts believe that natural gas is the cleanest of the fossil fuels.
As the world energy balance tilts towards natural gas, investors and operators are determined to ensuring that the process of producing natural gas is environmentally friendly. The International Energy Agency, IEA, reports that about 43 percent of the world’s natural gas reserves, excluding North America, are sour. In Russia, the world’s largest natural gas producer, 34 percent of total reserves are sour gas. Up to a third of the world’s natural gas reserves contain high concentrations of sour and contaminated gas, with the Middle East a region where such fields are prevalent. At the Soar Oil and Gas Technology, SOGAT 2019 conference, in Abu Dhabi, UAE on May 1, a new technology approach would be presented to address H2S removal in small amine and claus process plants. The process for liquefying natural gas in order to be transported requires extremely low concentrations of CO2—less than 50 parts per million, ppm. This is because when the gas is cooled for liquefaction CO2 will freeze, causing blockage of flow lines and other operational problems.
With global capital expenditure, CAPEX expected to reach around US$1.13 trillion by 2025; Nick Coles, conference director at Dome exhibitions believes the future looks bright for natural gas projects. In the gas processing, Russia is to spend US$40.8 billion on 13 new projects, expected to come online during the outlook period. On the LNG liquefaction front, the US leads with estimated CAPEX of US$216.4 billion on 32 upcoming liquefaction terminals by 2025, while China leads in regasification CAPEX, with US$18.1 billion to be spent on 22 upcoming regasification terminals.
In the underground gas storage segment, Turkey leads with estimated CAPEX of US$11.4 billion to be spent on seven planned gas storage terminals by 2025, while for liquids storage terminals, the US leads with CAPEX of US$9.3 billion expected to be spent on 32 upcoming projects. Ten countries hold more than two-thirds of the world’s total proven natural gas reserves, with Russia, Iran, Qatar, the US and Saudi Arabia in a descending order. Nigeria is the ninth in world’s total proven natural gas reserves. With a production of 734.5 billion cubic metres, bcm in 2017, the US is the top natural gas-producing country in the world, though it does not lead in terms of reserves, according to BP’s 2018 Statistical Review of World Energy.