Page 40 - ITAtube Journal 2/2019

Technical Papers
tion of renewable energies. The inauguration is planned for early 2020. The power plant will provide approximately one million house- holds with electricity.
An existing plant in Marcos Paz in Buenos Aires Province, Argen- tina will be converted into a combined-cycle power plant in a project called Genelba Plus. The conversion will increase the capacity of the power plant from 168 to approximately 364 mega- watts. It is scheduled to come into operation in mid-2019. In 2021, a new combined-cycle power plant in the Republic of Tatarstan in the Russian Federation will start gen- erating electricity. It is planned to have an available capacity of 495 megawatts.
As a replacement for
old coal- red power plants
The Scottish energy company SSE Plc. and Siemens have announced that they are working together to construct the Keadby 2 com- bined-cycle power plant in Lin- colnshire, UK. Siemens will deliver the power plant ready for use. The equivalent of approximately 400 million euros is being invested by SSE in the construction of the new power plant, which will have a capacity of 840 megawatts and an ef ciency of 63 percent. Com- mercial operation of Keadby 2 is planned for 2022, as coal- red power plants are shut down.
The new combined-cycle power plant in Lincolnshire ts in with the SSE’s objective to strengthen its activities in offshore and onshore wind energy. “Com- bined-cycle power plants will help to exibly support the electricity grid. “They provide an important contribution to support the United Kingdom in developing renewable energies and thus achieving its
carbon dioxide reduction targets,” Martin Pibworth, SSE’s Wholesale Director, points out.
Renewable energies are also impor- tant for the energy revolution in Germany. According to the govern- ment, the share of renewable ener- gies in power generation should increase to 80 percent by 2050; its current share is approximately 20 percent. “This energy revolution will only succeed with a restructur- ing of the whole energy concept,” emphasises the German Aerospace Centre’s (DLR) Institute of Propul- sion Technology. At the same time, a secure energy supply is essential for Germany as an industrial centre since the economy depends on it. “With signi cant increases in nat- urally- uctuating renewable ener- gies such as wind and solar power, state-of-the-art conventional power plant concepts are needed in order to guarantee security of supply.” The institute favours com- bined-cycle power plants, which could ful l the role of fossil fuel support for the energy transition. With over 60 percent thermal ef - ciency, they are already the most ef cient conventional power gen- eration technology on the market.
High-pressure valves for
various sectors
Furthermore, electricity from modern combined-cycle power plants produces only half as much carbon dioxide as electricity gen- erated by modern coal- red power plants. The construction times are also shorter in comparison, and the construction costs con- siderably lower. Combined-cycle power plants produce both elec- tricity and heat. Manufacturers of high-pressure valves are thus part of forward-thinking power genera- tion technology.
However, combined-cycle plants are not yet running at full capac- ity. The price of electricity can sometimes be a problem. If the market price is higher than the cost of generation, operation of the power plant can earn pos- itive pro t margins. “If not, the power plant remains shut down and is virtually in standby mode, because otherwise we would have to pay more,” explains Martin Buschmeier, director of the Trianel gas- red power plant in Hamm. It is calculated that the econom- ical operation of gas- red power plants on a full-cost basis is not yet possible in the current elec- tricity market.
But this situation will not cause manufacturers and dealers of high-pressure valves any major headaches. There are just too many ways to use them. That is why AS-Schneider designs high-pres- sure valves for measurement and control technology applications in a wide range of sectors, including chemical and petrochemical plants and the crude oil and natural gas industries. “Pressures here can often reach several thousand psi (several hundred bar), and the process media can be aggres- sive and harmful to people and the environment,” the company explains. Most valves very quickly reach their limits under these conditions.
Variable modular design
This is how the high-pressure valve is designed: the spindle sealing (packing) is made from the polymer PTFE. “Furthermore, the high-pressure valves bene t from a metallic rear seat, which provides an additional seal against the outside environment, reduc- ing the demands on the packing,” according to AS-Schneider. This
ITAtube Journal No2/May 2019
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