Turbine components, cleaning

The gas stream must have extremely low levels of impurities not only to avoid pollution but to protect turbine components from chipping or corroding. As in the case of clean combustion, much of the sulfur-containing gas can be captured by a sorbent injected into the gasifier. 

The turbine flow-meters are suitable for use at high pressure up to 4000 bar. The measuring device could be easily mounted into high-pressure tubes. For this purpose, small instruments have been developed [56]. The use of turbines is limited to the measurement of flow of extremely clean components. Fig.4.4-2 shows an example of such a device. Other devices are so-called helical- and gear flow meters which are in use up to pressures of approx. 400 bar [56]. 

For this concept atmospheric gasification, with air as the gasification medium, has been chosen. In the future pressurised systems may be preferred. All main components of such a system do exist on the market gasifier, cleaning system, coir iressor, Fischer-Tropsch unit, gas turbine, and the steam cycle. Large-scale, as well as small-scale (15 to 100 MW ) systems belong to the possibilities. 

Consequently, the vast majority of SCF applications are based on CO2 near the GL critical point, with a possible admixture to support the ability for solvating dipolar components. The extraction of carcinogenic aromatic hydrocarbons and their nitro derivatives from diesel particulates by CO2 + toluene or methanol SCF can serve as an example. CO2 based SCF also helps in cleaning polyethylene from undesired polymer additives. In a similar way one can consider technologies focused on so called h q)er-coal, an extremely pure and environment friendly fuel for turbines in power plants. Recently, the first power plants based on this idea are being constructed in China. The removal of pesticides from meat, decaffeinated coffee and denicotinized cigarettes are the next society-relevant applications. Noteworthy is the h q)er-oxidation with supercritical water and bitumens extraction based on supercritical toluene. The latter system is also used for the liquefaction of coal. ... 

Decontamination of larger equipment items, such as the condenser and turbine units, was veiy effective. These decontamination efforts released about 90 percent of these components to the on-site scrap metal recycler. The Spent Fuel Pool was also cleaned out, drained and repainted. A thorough general cleanup of the EBWR Building (Shell) was conducted. This Phase completed in late 1989. 

Some gas turbines run on many different kinds of fuel—gas, diesel, and residual fuel. The life of their hot-section components will be very different, depending on the type of fuel they are nmning. Natural gas is generally a clean fuel and causes the least toll in parts life in a gas turbine. 

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