Why is Pakistan's coal-fired power plant eco-friendly?

[Beast]

 

[ozranger]

I think it is actually ultra supercritical, one level up compared to supercritical, isn't it?

 

[Beast]

China modern coal fired power station standard is so strict that EU coal power station will not passed into China. There is reason why a sudden rekindle interest of coal power station in China.

It still emission CO2 but at 1/10 of what EU plant do.

 

[niaz]

Before commenting on the video kindly let me explain the difference between Supercritical & sub-critical power plants.

When you boil water, the water temperature does not increase beyond 100 deg C, instead, the heat is absorbed by the water converts into steam, but the temperature of steam remains at 100 deg C. The heat required to convert water into steam is called latent heat which is 586 calories per gram of water. The temperature of steam only increases after all the water has been converted into steam and if the system is under pressure.

All with the knowledge of ‘Thermodynamics’ know that most fluids have a critical temperature & pressure. This is the point where the liquid turns to vapors without any heat lost as ‘Latent Heat’. The critical stage of water arrives at 374 deg C and at a pressure of 3, 200 psi (22.12 MPa to be exact). At this point, the Latent Heat is zero, and the Density of water, as well as steam, is the same at 324 Kg/cubic meter.

Nearly all modern coal-fired plants are Super Critical, meaning that operating temperature & pressure is in excess of the critical point of water. The main advantage is an increase in thermal efficiency which can be as high as about 45% whereas even a most modern sub-critical power plant would be no more than about 35% thermally efficient. Increased efficiency means less coal is used to generate the same quantity of steam.

Because of the very high pressure, supercritical power plants were considered too expensive, and the first plant ever to use supercritical technology was not built until 1967. However, these days supercritical power plants are the norm, and even an ultra-critical coal-fired power plant (760 deg C and 5,000 psi) went into operation in 2012 in Arkansas.

Nearly all coal-fired plants in Europe are now fitted with particulate matter removal, sulfur dioxide removal, and nitrogen oxide removal equipment. But since the supercritical power plant burns less coal, the power plant produces less sulfur dioxide, less nitrous oxides, less smoke, and less carbon dioxide. Despite a super-critical coal-fired plant producing about 20% less carbon dioxide; the plant would only be less pollutant but not classified as ‘Environment Friendly’ unless a ‘Carbon Capture’ plant has been installed as well.

It is true that most of the European and US coal-fired plants emit more carbon dioxide but only because these were designed before the supercritical technology was made economically viable.