As soon as mercaptan removal units in gas refineries of South Pars Gas Field in the southern Bushehr Province become operational, natural gas will be replaced with condensates in thermal power plants, managing director of Iran's Thermal Power Plants Holding Company said.
“Condensates contain a gas called mercaptan that must be removed before it can be used as feedstock, otherwise a foul smell will waft up as it burns,” Mohsen Tarztalab was also quoted as saying by ILNA.
Mercaptan removal units are expected to become operational in Asalouyeh in November and till then, the addition of condensates to thermal power stations’ fuel inventory is out of the question, he added.
Tarztalab noted that a pilot project was being carried out at Asalouyeh Power Plant in Bushehr Province, but it was stopped due to the foul smell given off by the power station.
Nonetheless, as soon as mercaptan is removed, the problem will be solved.
“The cost of generating electricity from gas condensates does not vary from natural gas,” he said, adding that the important point is that Iran has a variety of fuels that should be used efficiently.
However, the advantage of using gas condensates in turbines instead of natural gas is that it has lower emissions and is more environment-friendly.
TPPHC, a subsidiary of the Energy Ministry, hopes the plan to use gas condensates for gas turbines will be implemented in winter.
A lean, premixed, pre-vaporized combustion technology has been developed that converts liquid fuels into a substitute for natural gas. This technology offers the possibility of using gas condensates for power generation in a gas turbines equipped with a dry low emission system. DLE is a technology that reduces nitrogen oxide emissions that exhausts out of gas-fired turbines.
Natural gas condensate is a low-density mixture of hydrocarbon liquids that are present as gaseous components in raw natural gas produced from gas fields.
As Iran increases gas production (1 billion cubic meters per day), gas condensate production is also rising. South Pars Gas Complex accounts for 92% of total gas condensate output, producing over 685,000 barrels per day, a part of which is sold to refineries and petrochemical complexes as feedstock.
With the Energy Ministry’s new decision, a part of the SPGC output will be supplied to power plants in winter.
Thermal power plants, which generate 80% of electricity in Iran, are seen as a major source of air pollution due to their emission of greenhouse gases.
Currently, 253 million cubic meters of natural gas is supplied to power plants across the country per day, the spokesman of the National Iranian Gas Company said.
Coal-Powered Stations
According to Tarztalab, coal accounts for up to 50% of total feedstock burnt in power plants in countries like Poland, Turkey, the US, India and China.
“Plans are in place to build coal-powered stations with a capacity of 5,000 megawatts in Iran over the next two decades,” he added.
Referring to the first coal-fired power plant in Iran, he noted that the project has registered 70% progress.
Located near the city of Tabas in South Khorasan Province, the power station will produce 650 megawatts and use feedstock from the nearby Mazino Coalmine that holds more than 600 million tons of in-place coal.
“Supplying equipment for the new power plant is the responsibility of Iran’s engineering and energy giant, MAPNA Group, and China’s Shanghai Electric,” the TPPHC chief said.
However, environmentalists have voiced strong opposition to the project, stressing that burning coal will add to the worsening pollution problems and to global warming.
Iran pledged at the Paris Climate Conference in 2015 to curb 4% of greenhouses gases by 2030 and raise electricity output capacity from renewables to 7,500 MW.
There is a robust consensus among international scientists and experts that coal has an adverse environmental impact.
According to reports, coal energy produces a tremendous amount of harmful emissions such as carbon dioxide and sulfur dioxide that contribute generously to climate change and global warming.
Diversification of Energy Sources
Nonetheless, proponents of the plan argue that building a coal plant makes sense because “it allows Iran to diversify its sources of energy, which now largely comes from thermal plants using gas".
They also claim that the relatively low cost of power generation from coal justifies such a project.
The Tabas power station, under construction in Dasht-e Kavir (the Great Salt Desert) in central Iran, will be equipped with advanced pollution-reduction systems.
According to latest reports, planned coal-fired capacity additions from a number of countries in and around the Middle East will add 44 gigawatts of new electricity generation capacity over the next decade.
Coal capacity in the region is typically less than that of other fuels, particularly compared to liquefied natural gas or petroleum-based fuels.
Turkey is the heaviest user of coal-fired power among these countries with a capacity of approximately 18.5 GW, followed by Pakistan (2.5 GW). The two counties plan to add more coal capacity over the next decade.
Egypt, Oman, Jordan and the UAE have no current coal-fired electricity generation, but they also plan to build coal-fired power plants in the near future, reports say.
