Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Siberian scientists learned how to reduce harmful emissions from HPPs

22.01.2018

A team of scientists from Siberian Federal University (SFU) and their colleagues from Novosibirsk and the Netherlands modeled the process of coal burning in HPP boilers and found out which type of fuel produced less harmful emissions. The study was published in Fuel journal.

Heat power plants (HPPs) supply electrical energy to many cities in the world. The production of heat and electricity starts with burning coal in a combustion chamber. Generated heat warms up the steam and smoke mixture that moves the turbine. This is how electricity is produced, and the warmth is used for heating. However, when coal is burned at HPPs, harmful nitrogen oxides are released into the atmosphere.


This is the results of modeled distribution of NOx in a combustion chamber: a) regular boiler, kg/m3; b) three-step combustion boiler with the use of mechanically activated micro-milled coal, g/m3

Credit: Alexander Dekterev

One of the most prospective emission-cutting technologies is post-combustion or three-stage fuel combustion. After the first combustion stage during which the main part of the coal burns out and the air is scarce, the remains of the fuel are transferred to a special area above the combustion chamber.

Additional fuel is also transported here. Nitrogen oxides react with the hydrocarbon forming hydrogen cyanide and molecular nitrogen, and the volume of nitrogen oxide emissions drops by about 10%.

"The environmental impact of oil and gas post-combustion is more evident, but we also have to work with coal. It has a great practical importance as many HPPs use it," explained Alexander Dekterev, a co-author of the article, candidate of technical sciences, and head of the department of thermal physics at SFU.

Many scientists conducted experiments in order to understand which properties of coal and combustion techniques allow for maximum emissions reduction. Recently physicists have offered to mill coal down not to average powder (with particle size of about 200 micron, like in facial powder) but to micro-particles (20-30 micron). This technique provides for a more stable flare in HPPs, as coal micro-particles are mixed better and burned quicker.

Previously this effect was demonstrated in small experimental boilers. The flame from the burning of coal micro-particles resembled that of burning oil, and the particles were almost invisible. Still it wasn't clear whether the effect would be the same in regular HPP boilers, and the scientists from Krasnoyarsk decided to model that.

They took a standard steam boiler BKZ-500-140 of Krasnoyarsk HPP-2 as a model, as all experimental data on it was available. The data were downloaded into the model and after that is was reconfigured taking the post-combustion into account. In the new model the basic fuel was brown Kansk-Achinsk coal, and the post-combustion fuel was formed by jet coal from Kuznetsk. According to initial calculations, the mathematical model implemented by the authors of the article in the in-house software correctly described the processes in the boiler.

The team modeled three burning schemes - with regular coal, micro-particle coal, and mechanically activated fuel. The latter variant proved to be preferable and led to 50% reduction in Nox emissions compared to the basic variant and by 20% to the regular coal.

The work might be of interest for developers and engineers working on the improvement of the existing boiler equipment and design of power blocks. The authors continue to develop mathematical modeling methods to improve burning technologies both for widely used and unconventional fuel types.

Media Contact

Yaroslava Zhigalova
press@sfu-kras.ru
7-391-291-2733

 @SibFUniversity

http://www.sfu-kras.ru/en 

Yaroslava Zhigalova | EurekAlert!

More articles from Power and Electrical Engineering:

nachricht Failures in power grids: Dynamically induced cascades
25.05.2018 | Technische Universität Dresden

nachricht Beyond the limits of conventional electronics: stable organic molecular nanowires
24.05.2018 | Tokyo Institute of Technology

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

If solubilty is the problem - Mechanochemistry is the solution

25.05.2018 | Life Sciences

Investigating cell membranes: researchers develop a substance mimicking a vital membrane component

25.05.2018 | Interdisciplinary Research

When corals eat plastics

24.05.2018 | Ecology, The Environment and Conservation

VideoLinks
Science & Research
Overview of more VideoLinks >>>