The Ghana National Gas Company (GNGC) says it is now in the market to scout for a prospective company that can buy its residual gas, Isopentane — a flammable liquid gas — for energy generation.
It is expected that any successful buyer of the gas will have the capacity to covert the Isopentane into an energy generation resource and allow Ghana Gas Company to commercialise the product in line with the country’s “no gas-flaring” policy.
According to the GNGC, the search for an Isopentane processing company is part of the plan to monetise all natural gas liquids (NGLs), including Isopentane — which is less than 0.5 percent of the gas extracted from the Jubilee Oil Field and processed by the Atuabo Gas Plant in the Western Region.
Petroleum Minister Emmanuel Armah Kofi Buah, alongside the Chief Executive Officer of the Ghana National Gas Company, George Sipa Yankey, disclosed this to the Government Assurances Committee last Thursday, saying that government is currently looking for a company that can use Isopentane to produce energy so that it will be commercialised rather than flared.
The announcement comes ahead of plans by the Ghana Gas company to begin full operations on April 1st, which will see the company ramp up its gas production and processing capacity from the current 74 million standard cubic feet to 150 million standard cubic feet.
Presently, the country’s major power generator Volta River Authority, which is the only company to have an off-taker agreement with Ghana Gas, is anxiously waiting for a company that can convert the Isopentane into gas that can be utilised.
“We are anxious to make sure that we monetise all the liquids…we have done a lot and we are going to make sure the Isopentane that is lifted is monetised as quickly as we can get a commercial entity to take those liquids,” he said
He noted that his outfit has been working with a company that is prepared to take that waste product and then convert it into gas; and so sooner than later after the agreement has been reached and the company sets up its plant, the waste product will be used to produce power of about 21 Megawatts that can be added to the national grid.
Mr. Sipa Yankey also explained to the Committee that Isopentane is actually a waste product from the gas processing , but added that GNGC is striving to monetise it because of the Ghana’s petroleum industry’s ‘no flaring’ policy.
“I don’t want us to leave here with any impression that we are burning money.
“The Isopentane in actual fact is a waste product in most countries it is flared. But we in Ghana, because of the [GNGC’s] zero-flaring policy, are dripping some of that into even the condensates that we produce for power production,” he added.
Mr. Sipa Yankey said: “We have been working with a company that is prepared to take that waste product and then convert it into gas; and so hopefully in the next few months, once it finishes the arrangement and the company gets its plant established, the waste product will be used to generate power of about 21megawatts — so it’s all part and parcel of a comprehensive programme that is being done. We want to make sure that every molecule of liquid is monetized”.
Isopentane
Isopentane, C5H12 — also called methylbutane or 2-methylbutane, is a branched-chain alkane with five carbon atoms.
It is an extremely volatile and extremely flammable liquid at room temperature and pressure.
The normal boiling point is just a few degrees above room temperature, and Isopentane will readily boil and evaporate away on a warm day.
Isopentane is commonly used in conjunction with liquid nitrogen to achieve a liquid bath temperature of −160 °C. It is 1% or less of natural gas.
In a related , the Ghana Gas Company says it is ‘happy’ with the speedy resolution of challenges posed by Tullow Ghana’s compressors at the FPSO Kwame Nkrumah that affected regular gas supply to the country’s gas processing plant sited at Atuabo.
Mr. George SipaYankey told the B&FT that: “They (compressors) have started working now. Tullow has rectified the problem and we are very happy with the state of the compressors on the FPSO.
“Tullow has assured Ghana Gas that it is able and ready to supply about 140 million standard cubic feet of natural gas daily for processing. The main challenge with off-taking the processed 140 million scf of natural gas from the FPSO is a lack of generating facilities to utilise or receive the processed gas.”
The compressor used by the oil company works in a similar fashion to pumps. It increases the pressure on a fluid and can then transports it through a pipe.
Tullow is responsible for the supply of gas from the Jubilee Oil and Gas Field to the country’s only gas processing plant sited at Atuabo in the Western Region, but challenges with its compressors in the past have limited the output to between 50 and 74 million standard cubic feet of gas per day (MMSFCD) during the commissioning stage of the Gas Processing Plant.
While gas supplied from the Jubilee Field may not be the sole answer to the country’s energy crisis, it certainly is an important component in reducing the current power supply deficit. That has plunged the country into power rationing over the past year.
The current power supply deficit has been necessitated by the poor inflow of water into the Bui and Akosombo Dams for hydropower generation, as well as funding challenges for crude oil purchases.
Producers expect a peak supply of about 80million standard cubic feet of gas from Nigeria and about 150 million standard cubic feet of gas from Jubilee Field in Ghana, bringing the total supply to about 220million standard cubic feet of gas per day.
Mr. Sipa Yankey added that so far, two units of VRA’s T1 plants at Aboadze have been operating satisfactorily for some time now, receiving an average of about 55 million scf of lean gas per day.
Currently, two thermal units of the VRA at Aboadze are now operated solely on gas supplied by the Ghana Gas Processing Plant which sources its gas from the Jubilee oil and gas fields.
The VRA says the two units at the Aboadze thermal plant are currently able to utilise the entire 50 million standard cubic feet of gas per day supplied by the Ghana Gas Company.
The coming on-stream of the country’s gas could mean a 20% reduction in fuel costs to the power industry, or savings of US$2billion over a 10-year period. For the industry as a whole, this is enough to fund one 400MW power plant every other year.
Again, it will reduce the cost of maintenance for thermal plants by some 50 percent, according to the VRA and increase the availability of thermal plants.
Aside from Jubilee, the country is expecting gas from other fields like Sankofa and the TEN project area.
Source: Bft