[Credit: Mitsui]

Good, some facts!

"The plant will be equipped with Ansaldo GT26 class gas turbines, with a net generating capacity of 235MW each, and two steam turbines with a capacity of 284MW each. The project will also comprise four boilers".

So somewhat bigger than I speculated and about 1,000 MW of waste heat to dump!

" Ansaldo Energia will supply the main power train equipment components, including, for each power plant, four GT26 gas turbines, four heat recovery steam generators, two steam turbines and six turbo generators, to SEPCOIII (Shandong Electric Power Construction Corp) of China "

Coal fired power stations installed Flue Gas Desulphurisation plants, passing the flue gas through limestone, to remove sulphur dioxide.  Initially this was an expensive exercise until someone found out that by forcing the oxidation a little further the end by-product was about 97% pure gypsum which could be sold to make plasterboard.  In the UK alone at least 500,000 tons per year of it is used in this way.  The FGD gypsum comes from power stations all over Europe who sell this by product to the plasterboard manufacturers for a tidy sum.

That's interesting, I know also that the ash is used in construction somehow.


Stephen

Stephen Biddle:

That's interesting, I know also that the ash is used in construction somehow.


Stephen

Breeze blocks https://en.wikipedia.org/wiki/Concrete_masonry_unit  can be made out of power station ash, with added cement.

The picture of the power station in Oman is using an air cooled condenser as against a cooling tower, which is historically more common in the UK. Both can be used by coal fired power stations and CCGT plants like the one in Oman. The third alternative is direct cooling, usually using seawater, but can be from lakes or rivers if the supply is adequate.

Direct cooling is the most efficient, followed by cooling towers, with air cooled condensers being the least efficient.

All UK nuclear power stations are direct cooled, but cooling towers are used in other parts of the world.

Modern UK CCGT power stations with cooling towers use the lower height forced air type i.e. they have a fan, rather than parabolic shaped type, which are more efficient, but more expensive.

The choice of cooling used for nuclear, coal, oil, gas and CCGT plants depends on water availability, environmental constraints and cost. The three cooling technologies will work in each case.

Lynton

I worked on the West Midlands power stations in the '70s and was told by one of the Scientific Services engineers that one of the cooling towers at Rugeley was a dry one whilst the remainder were wet. The dry one was also used as a spares store.

There are proposals for extracting power from the small temperature difference between surface and deep ocean water in places like Hawaii, using ammonia as a working fluid. Surely a coal-fired power station has much higher residual heat than that. So why not put an ammonia-cycle turbine or Sterling engine on the back end instead of blowing all that heat away as steam? You could do the same with any significant waste heat, be it from a steam turbine or a diesel.

Cooling water leaving the condenser of a steam turbine is at about 30 degrees centigrade. Extracting useful energy from this is expensive in capital terms. A CHP plant provides heat, hot water or steam, at a higher temperature, but at the cost of reducing the amount of electricity generated i.e. the electricity generating part of the cycle is less efficient, but if the heat is used effectively the overall cycle is more efficient.

At one time Drax power station's cooling water was used for heating greenhouses growing vegetables, tomatoes I think, but it wasn't economic and stopped.

Lynton

Or use cooling towers for community heating systems for homes, sports centres, pre-heating water for domestic and commercial use, etc, instead of venting valuable steam into the air as 'cloud factories' as my children used to call them?