Removing sulfur dioxide from exhaust gases produced in thermal power plants is not an environment-friendly practice that is why none of these stations in Iran are equipped with special devices that can be installed on smokestacks, the head of Environment Protection Department at the Thermal Power Plants Holding Company said.
“Not only does the process produces gypsum plaster waste that is hazardous for the ecosystem, but it also raises water consumption in the facility by at least 50%,” Sanaz Jafarzadeh was also quoted as saying by Barq News.
“Sulfur removal process from liquefied fuels like mazut and diesel should be done in refineries and not in power plant,” she added, noting that the quality of mazut delivered to thermal power stations is very low, so when it is burnt instead of natural gas, it adds to the air pollution menacing large cities.
Jafarzadeh said there are about 100 thermal power plants in the country, of which 20 have to burn mazut in winter when natural gas delivery decreases due to massive consumption in the household sector.
Blaming other factors such as the large number of gas guzzlers in megacities, she argued that power stations in the proximity of big cities like Tehran are not allowed to use liquefied fuel in winter.
Despite what the official claims, Shazand Thermal Power Plant in Markazi Province has started burning mazut since last month, 50 days sooner than the time it used the liquid fuel last year.
A steam turbine power plant with a capacity of 1,300 megawatts, it runs on dual fuel. The primary fuel used for power generation is gas. However, in case of gas shortage, the plant can also run on mazut.
Mazut is a heavy, low quality fuel oil used as an alternative to run thermal power plants and factories.
Gas Supply
With the onset of winter and higher home gas consumption, gas supply to power plants may be disrupted as priority shifts to households, which forces power plants to use liquid fuel.
Using mazut has been a routine in Shazand power plant in previous years during winter as it is not provided with enough gas. The power station consumed more than 470 million liters of mazut last year, registering a new record in this regard.
In the past 30 days, brownish smoke associated with burning mazut rising from the power plant’s flue-gas stack has been seen but no comments have been made by the relevant authorities and no response has yet been given to alleviate the concerns of people.
The burning of natural gas produces pale white smoke, whereas using mazut for energy production leads to the emission of brown smoke that is carried over kilometers by wind and remain in the air for hours, adding to the issue of air pollution.
Mazut is not suitable for power plants because it doubles maintenance costs, increases water consumption and decreases output. However, when power plants do not receive adequate gas, they need to either reduce output or burn liquid fuel to avoid outages in regions under their electricity coverage.
