HiQ speciality gases and equipment from The Linde Group have a role in many areas of power generation.
In oil, coal and gas-fired power plants, high-precision gas mixtures and high-purity instrument gases are used to monitor flue-gas treatments and calibrate continuous monitoring systems for stack emissions. Accurate measurement helps the power plant run at peak efficiency and ensures compliance with environmental legislation. In addition to concerns over the more conventional pollutants - nitrogen oxides (NOx) and sulphur oxides - reducing carbon dioxide and mercury emissions has also become an enormous proposition for the power generation industry. Coal, oil and gas-fired plants face challenging circumstances relating to the need to meet increasingly strict regulatory requirements.
There is a clear trend moving from process control to legal compliance and further to economic emissions trading. To support legal compliance and emissions trading, metrology has progressed to increasingly higher levels of precision and accuracy. This development has been enabled by improved international standards and global recognition of these standards, such as ISO 17025 and the ISO Guide 34. However, many pockets of local, national and regional requirements are still in place, for instance the GBW standards in China and the US EPA.
To keep pace with technological advances and legislative requirements in the power generation industries, The Linde Group ensures its calibration gas mixtures remain at the forefront of technology. For example, Linde was the first company to offer a gaseous mercury standard able to measure mercury as low as a parts-per-trillion level, for the monitoring and detection of emissions from power-generation plants. Waste-to-energy power generating facilities will also use high-purity gases and mixtures for de-NOx process control and stack emissions monitoring.
Nuclear power stations use instrumentation gases with nuclear counter devices to check the environment and/or specific items for radioactivity. These counters work by detecting the ionisation produced by a radioactive particle. Every time a particle of radiation is detected, the counter records it, then the total number of particles recorded over a period of time indicates the amount of radiation present. Typically, this is done over one-minute intervals, resulting in counts per minute (CPM). Higher CPM indicates increased radiation levels. A proportional counter is a measuring device that counts particles of ionising radiation and measures their energy. It works on the same principle as the Geiger counter, but uses a lower operating voltage.
Several gas mixtures are used for the measurement of radioactivity and ionisation, such as carrier gas for proportional counter P5 and P10 mixtures (5% and 10% methane in argon respectively), carrier gas for Geiger counters (0.95% isobutane in helium) and quench gas (1.3% n-butane in helium).
In modern solar power generation, photovoltaic cells are used to capture the sun's rays. These cells are manufactured using a range of different technologies, but each process will use high-purity gases such as hydrogen and nitrogen along with electronic grade semiconductor gases and chemicals.
Speciality equipment such as Baseline and Redline cylinder regulators and gas supply systems are recommended to be used in many areas in order to control gas cylinder pressure while ensuring that the purity of the speciality gases is not compromised.
The Linde Group is a world-leading gases and engineering company with around 62,000 employees in more than 100 countries worldwide. In the 2012 financial year, Linde generated revenue of EUR 15.280 bn. The strategy of the Group is geared towards long-term profitable growth and focuses on the expansion of its international business with forward-looking products and services. Linde acts responsibly towards its shareholders, business partners, employees, society and the environment - in every one of its business areas, regions and locations across the globe. The company is committed to technologies and products that unite the goals of customer value and sustainable development.