Many nations of the world seek to achieve a clean environment through the production of clean oil and gas and reduction of Green House Gas (GHG) emission and putting an end to flaring due to its negative environmental impact.
To this effect, many of these nations are parties to one environmental treaty or the other.
The use of renewable energy has been a major way forward in this regard.
However due to the capital intensive nature of renewable energy various efforts has been made to make fossil fuel cleaner or reduce the impact of flaring.
Over the years many production techniques and technologies has been developed in a bid to reduce flaring and make fossil fuels cleaner, profitable and more environmentally friendly, such technologies includes Compression of natural gas, gas to liquid conversion (GTL), Allam cycle and green completion.
This article makes a comparative study of three selected technologies, in other to give incite on which technology can be more sustainable to the energy industry.
A reduction in green house effect has been a major source of concern to the global energy industry, during production, well testing and some other completion process green house gas are released, stored or flared, flaring is not environmentally friendly because it does not only increase the green house effect but also distorts ecological balance.
In a bid to cut down flaring and maximize the use of clean energy source such as natural gas, several countries of the world adopted various gas utilization policies, programs and technology in bid to ensure that the use of fossil fuel is sustainable.
Despite these advances in technology, gas flaring is rather on the increase, according to a data released June 2019 by world bank’s Global Gas flaring Reduction Partnership (GGFR), billions of cubic meters of natural gas is flared annually at oil production site around the world, global gas flaring showed a 3% increase in 2018 to 145 billion cubic meters of gas, which is equivalent to total annual consumption of central and north America.
Gas flaring wastes a lot of useful energy regardless of the reason behind it.
Top Ten Flaring Countries
The following technologies were developed in a bid to ensure the proper utilization of cleaner energy sources such as natural gas and other gases.
CLEAN OIL AND GAS PRODUCTION TECH
Gas to liquid Technology (GTL)
Gas-to-liquid technology was developed in other to produce clean liquid fuels from gas, it is not a new technology as it was developed and used by the Germans during World War II.
The gas conversion is either done directly or through a syngas in a process known as Fischer-Trospch process this conversion can yield a variety of clean fuels such as diesel, gasoline and Naphtha. GTL products are known for their high quality, trials has shown that GTL fuel can reduce Nitrogen oxide (NOx) emission by up to 70% and particulate matter (PM) by up to 90% compared to conventional diesel.
Indeed GTL fuels are clean energy source when compared to the conventional refinery process. However, there are currently (as at the time of this publication) six GTL plants around the world two are under construction in South Africa and Uzbekistan, this is due to the capital intensive nature of the plants and other factors that will be subsequently outlined, since natural gas is the cleanest burning fossil fuel, GTL products are seen as way forward in the reduction of GHG emission.
The Clean Energy of “Green Completion Technology”(REC)
After oil and gas wells has been drilled special installation and operations are carried out to bring the well to flow, the stream of fluids during the well completion process is referred to as “flow back”.
During completion, the reservoir is connected to the wellbore allowing flowback of drilling and reservoir fluid.
(Water, gas, oil, mud, etc) if the completions involve hydraulic fracturing there is usually a high rate of flowback when compared to the conventional well completion due to the large quantities of water and propant used to fracture the reservoir.
Sometimes it takes more than one week to complete during which the flow back is released to an open pit or tank where the gases are either vented or flared depending on the prevailing regulatory practice and operators tradition.
If the gas is vented it may generate a significant amount of methane and hydrocarbons to the atmosphere and if flared may also generate a significant amount of carbon di oxide gas, both flaring and venting results in lose of a clean energy source, and hence considered wasteful.
In other to offset the losses of Methane and other hydrocarbon during flowback a technology known as “Reduced Emission Completion”(REC) also known as green completion was developed.
REC is an alternative practice that captures the produced gas during well completions and workover operations, it is brought temporarily to the well site to separate gas from liquids and solids in the flow back stream producing a gas stream that is nearly ready for sales pipeline.
Green completion can provide environmental and economic benefits to the oil and gas operation as the incremental cost associated with the capital investment of acquiring green completion or equipments rental and labor can be offset by the revenue generated from sales of gas.
Reverse Combustion Technology/Carbon Engineering(RCT)
In recent past various attempt has been made to capture and sequester carbon in underground reservoir in a bid to rid the atmosphere of carbon di oxide, however this method of carbon reduction and utilization has no major proven means of giving individuals and or organizations involved in it a Return of Investment (ROI).
Also attempts has been made to thermally disintegrate captured carbon di oxide into carbon monoxoide and oxygen, but this process consumes a lot of energy because carbon di oxide is chemically stable this has led to eyebrow being raised because it is not energy efficient.
Carbon engineers’ captures carbon directly from the atmosphere purifies it and produces a pipeline ready compressed CO2 gas using energy and water.
The co2 can then be combined with non fossil fuel generated hydrogen to produce ultra low carbon intensity hydrocarbon fuels such as gasoline, diesel and jet fuel, in a process similar to the F-T process.
The reverse combustion technology is designed to capture the end products of combustion (predominantly co2) just before it is released to the atmosphere and utilize it.
The system is designed to mimic photosynthesis. It is made up of solar receptor and a nano catalyst ,incident sun rays activates the catalyst and breaks down co2 to co & O2 and also breaks up H2O into Oxygen and hydrogen, the co and the h2 produced are mixed up to produce a hydrocarbon similar to the F-T process the produced hydrocarbon can then be used to produce ultra clean liquid fuels such as high cetane diesel and gasoline.
|MATURITY||Has been in use in the industry for many years||Has also been in use in the industry for a good number of years||An emerging technology, not yet extensively tested|
|AVALABILITY||Not readily available, although modular GTL are being developed||It is available for sales and rent.||Currently undergoing commercialization|
|ECONOMICS||GTL plants are capital intensive. GTL plants thrive in areas where there are more gas reserves than oil. The economics depends on the price of liquid petroleum products.||Cost of buying and setting up of REC can be offset with the profits made from sales of produced gas. Hence the economics depends on the price of gas||RCT offers a reasonable return of investment, as it converts what has been considered as waste into valuable products.|
|ENVIRONMENTAL IMPACT||It discourages venting and flaring while encouraging the utilization of natural gas in the production of clean liquid fuels with high quality that burns with reduced emission||Helps to prevent flaring and venting at well completion and production platforms||Can Collect CO2 before it is released into the atmosphere and turn it into valuable hydrocarbon, mimicking the natural photosynthetic process. Hence even when flaring must be carried out for safety purposes the air wil not be polluted|
|SOCIAL IMPACT||Creates employment or Job opportunities||Creates employment or Job opportunities||Creates a new area for study research and development.|
|RANGE OF APPLICATION||Applicable in areas with high gas reserves, gases from onshore platforms can easily be channeled to a GTL plant. However it is difficult to apply the GTL process in offshore situation||Can be applied in most production platforms as its more concise compared to GTL plant||Some are built modular such that it can easily be connected with chimney , flare stations, to process co2|
Conclusions and Recommendations
The GTL plants and REC technologies has offered a meaningful way of utilizing gas and hence mitigating global warming, however the capital intensive nature of GTL plants and their economic dependence on the price of liquid petroleum products has also been an area of concern.
It is also challenging to set up a GTL plant in an offshore environment.
On the other hand RCT is offering the energy industry a chance to eat their cake and have it again as it not only allow a guilt free combustion but also offer the rare opportunity of turning what was once perceived as total waste into a valuable feedstock.Ugochukwu Uche Sosthenes
But the technology yet to be extensively tested!
Since the RCT is still an emerging technology compared to other clean fuel processing technology, producing companies should invest in as it promises to be a veritable tool in the production of ultra clean fuels.
More research work should be carried out on its viability and improvement.
Current fuel use trends put the world on the path towards a dramatic rise in average global temperature.
The cleaner fuels R&D portfolio can help stave off that threat while increasing economic competitiveness and energy independence.
But if there is massive and constructive investment in the carbon engineering field and further research work to better GLT and improve the RCT can go a long way to set the world on a part to safe environment, competitive industry and sustainable energy industry. RCT now offers a real field for research and development.
It may cost us a lot to afford clean energy, however,we cannot afford to continue harming our planet, just as some persons spend fortunes wile trying to save their lives, genuine concern for the earth will make us to save it no matter the cost.Ugochukwu Uche.
- Top Ten Flaring Countries
- Gas to liquid Technology (GTL)
- The Clean Energy of “Green Completion Technology”
- Reverse Combustion Technology/Carbon Engineering
- Conclusions and Recommendations