IGCC technology - High performance, low emissions
Since the 1950s, Japan has focused on using exhaust gas treatment technologies and equipment in coal fired thermal power plants to control air quality. Manufacturers of coal fired thermal power plants have always paid much attention to the development of low-heating value and high-sulfur coal combustion technologies, which however have the potential to significantly reduce the toxic gases released to the environment such as NOx, SO2, CO2, etc.
Currently, the ultra-supercritical coal combustion technology (USC) is an advanced technology being used in many countries, which can improve the generation efficiency up to 42.5%, with the fuel consumption rate of only 0.425 kg per kWh.
Japan is the leading country in developing high - performance technology thanks to the integrated coal gasification combined cycle – IGCC technology, which has been successfully tested in Osaki (Hiroshima). Japan has been constructing thermal power plants using this technology in Nakoso and Hirono (Fukushima). This solution aims to improve the efficiency of coal use, which allows the use of low quality coal (Bituminous A, Lignite); in particular, it can produce gas for generating electricity through gas turbines or steam turbines, like the natural gas combined cycle.
According to Mr. Takehiro Katsushi, Head of Coal Division, Department of Fuel Resources under the Energy Resources Agency of Japan (METI), the new feature of this technology compared to USC (ultra - supercritical) technology is the possibility to increase the generation efficiency by about 46 - 50%. In particular, the CO2 volume that can be separated and captured is much higher than that of conventional coal thermal power technology, thus CO2 emissions decrease by 20% compared to the USC technology.
Coal port of Vinh Tan 4 Thermal Power Plant
Coal fired thermal power development in Vietnam
According to international experts, at present, many coal fired thermal power plants in Vietnam are using modern technologies, similar to those being used in the region and the world, meeting environmental requirements. In particular, some power plants such as Vinh Tan 4, Vinh Tan 4 Extension, Duyen Hai 3 Extension, are applying supercritical and ultra – supercritical technologies, improving power generation efficiency and reducing CO2 emissions. Power plants those being constructed in the previous periods are also prioritized to be additionally invested with the aim of upgrading technological equipment lines, increasing capacity of power units and reducing impacts on the environment.
However, with the average growth rate of Vietnam's electricity demand of about 10% per year, in order to ensure national energy security, further development of clean coal thermal power plants is essential to meet the electricity demand for socio-economic development in association with environmental protection.
According to Mr. Takehiro Katsushi: “The application of new technologies, from supercritical, ultra - supercritical and followed by integrated coal gasification combined cycle will enable coal fired thermal power plants to operate in a sounder and cleaner manner. Vietnam is fully capable of developing this super clean coal thermal power generation type. After the success of adopting IGCC technology in Japan, we look forward to cooperating and building a typically environmentally friendly coal fired power plant in Vietnam”.
Mr. Takehiro Katsushi noted that, in addition to increasing the efficiency of electricity generation, to mitigate environmental impacts, coal fired thermal power plants need to strictly implement measures to remove toxic substances before being released to the environment. Results of environmental impact mitigation by advanced technologies should be regularly assessed.