OSTRAVA, IT IS DEDUSTED!!!
The new dedusting facility in ArcelorMittal will significantly reduce dust emissions
21 October 2011, Ostrava –Today, company ArcelorMittal launched the latest and high-performing facility for the dedusting of the operation of iron ore sintering (the so-called agglomeration), three months before the scheduled deadline. This purely environmental investment with the value of CZK 1 billion will reduce dust emissions from Agglomeration North to less than 20 mg/m3 (from the present 50 mg/m3 allowed). Yearly emissions total of the dust from the agglomerations which are an important part of the liquid state metal production will thus drop by 270 tons per year.
“The dedusting of Agglomeration North is a major investment of ArcelorMittal Ostrava. I am happy that we can unpack this first “gift” a few months before we unpack the Christmas boxes,” Company CEO, Augustine Kochuparampil, said.
The super-efficient fibre filters can capture by 70% more of dust particles than the current electrostatic filters. Moreover, the mufflers installed in the giant piping will reduce the noise level of the filter by 15%, which is important as it will be in operation together with the other filters in the company round-the-clock. The efficiency of the facility is 99.9 % for dust particles PM1, PM2.5 and PM10 (designation of dust particles according to their size).
There are only six facilities with the fibre filters technologies in operation for the de-dusting of combustion gases of metallurgical agglomerations in entire Europe. The solution used in ArcelorMittal Ostrava is even able to capture up to 60% of sulphur dioxide and the same amount of dioxins thanks to the additional reactor.
How the New Facility Works
The new facility works similarly to a vacuum cleaner, only many times a bigger one. The combustion gases are exhausted from electrostatic filters onto special textile fabric on the surface on which the dust particles are captured. Once the entire fabric is covered by the dust layer, dust is shaken off of the fabric surface. Dust is then led to the container and disposed of.
A part of the technology is also equipment with a system of inside lamellas which reduce noise, and a reactor in which SO2 content in the combustion gases is lowered by dispensing hydrated lime. Toxic dioxins will be removed with the use of lignite coke.
Construction
The contract with the CZK 1 billion project supplier, German company Lühr Filter, was signed in 2008. In 2009, project preparation works took place and the construction of the facility for the de-dusting of the iron ore sintering operation (the so-called agglomeration) commenced in February 2010. Domestic companies participated in the design, construction and assembly works as sub-suppliers, as well. Among the most important companies were for instance ZVVZ-Enven Engineering, a.s., VS-Invest a.s., Hutní projekt Ostrava a.s., ELDAT a.s., ElLCOM, a.s., MROZEK, Elektromont Brno, a.s., Omega-Teplotechna Praha a.s., ECM ECO MONITORING spol. s r.o., and SOUND TECHNOLOGIES for the foreign companies.
The Filter Wins an Award for Benefit to the Environment
At the beginning of October, the project of the dedusting of Agglomeration North won an award for the environmental benefit, Český PATRON. The price is awarded by Czech Chamber of Commerce under the aegis of the Ministry of the Environment. The expert jury appreciated the project as the most important corporate contribution to the environmental protection in the Czech Republic. “We very much appreciate Český PATRON award; for us, it is a confirmation that the path of environmental investments intended to make the life of inhabitants of Ostrava and its surroundings more comfortable, is right,” Petr Baranek, CGO of ArcelorMittal Ostrava, said during the award presentation.
ArcelorMittal Ostrava a.s. is the largest metallurgical company in the Czech Republic and belongs to the largest global steel group ArcelorMittal. Annual production capacity of the company is 3.6 million tons of steel, of which approximately 50% is exported to 50 countries all over the world. It employs nearly 5 thousand people or almost 9 thousand, together with its subsidiaries. The average wage of its employees was CZK 30,816 in 2010. The single shareholder is company ArcelorMittal Holdings A. G.
Detailed Technical Information
What Is the Agglomeration, How the Current and New Filters Work and How the Emissions will Be Reduced
Agglomeration Operation
The agglomeration operation produces agglomerate as one of the components of the metal-bearing charge of the blast furnace to produce liquid-state pig iron. The input raw materials for the agglomerate production are crushed dust ores with content of iron oxides, coke dust as the fuel and crushed lime as the bonding agent. The agitated mixture is poured onto the agglomeration belt in the layer of approximately 40 cm and is ignited with gas burners. During burning of the coke dust, temperature of up to 1,450 Celsius degree develops at which the mixture sinters and forms agglomerate. Agglomeration operation North works with three agglomeration belts 38 m long and 2.5 m wide. During many chemical reactions, also gas products (combustion gases) and dust are developed apart from the agglomerate.
Agglomeration (iron ore concentration plant)
Electrostatic filters (for dedusting to meet current limits of up to 50 mg/m3)
Fibre filters hall (construction commenced on 18 February 2010, level of dust to be reduced to less than 20 mg/m3)
Construction Specifics
The facility construction commenced with excavation of 14 pots with depth of 22 meters. The main reinforced concrete pilots of 120 cm in diameter were built into them holding the entire steel frame of the dedusting facility. The entire facility covers area of approximately 60 x 60 metres and it is 22 metres high with smoke stacks of 80 metres in height.
The steel frame holds 12 filter chambers. The area total of the filters fibre intended to capture the combustion gases dust is 44,000 m2 (almost 7 soccer playgrounds).
Combustion gasses are supplied and taken away through steel piping of 3.9 m in diameter containing also the mufflers to reduce the noise produced by the flow of the combustion gases in front of the exhauster. This equipment has dimensions of 4.5 x 4.5 metres with length of 6.5 metres and a system of inside lamellas reducing the noise.
Electrostatic Filters (Current Dust Elimination Technology)
Combustion gases are sifted through a layer of a mixture under the agglomeration belt into the collector and then go to the current dedusting facility – electrostatic filters. Dust particles gain electric charge there and during their further passage, they are captured on metal plates (electrodes) with the opposite charge. The efficiency of these filters allows complying with the current limits (50 mg/m3), however, it is not sufficient for the future limits (20 mg/m3).
Fibre Filters Lühr Filter (New Technology)
Fibre filters are currently the most efficient and latest technology of combustion gases purification. Combustion gases pass from electrostatic filters to the next chamber with hundreds of wire pipes wrapped in a special textile fabric from the outside. Combustion gases are sieved from the chamber to the pipes and the dust particles are captured on the surface of the fabric. Once the fabric is covered by the dust layer, the dust is shaken off of the fabric surface with pressure air jet. The dust falls into the bottom conic part of the chamber from where it passes to the container to be disposed of. Purified combustion gases which pass through the fabric layer are exhausted into the smoke stack with a minimum content of dust particles. The producer guarantees unchallenged reduction of dust content to less than 20 mg/m3, and therefore the full compliance with the future standard. A part of the dedusting facility is also a reactor in which SO2 content in the combustion gases is lowered by dispensing hydrated lime (acid rain). Toxic dioxins will be removed with the use of lignite coke.
The current emission top limit allowed by an integrated permit for both agglomerations is 850 t/year. Emissions total subject to this limit were 704 t in 2010. Agglomeration North accounted for 375 t/year and Agglomeration South accounted for 329 t/year.
The installation of fibre filters in Agglomeration North can guarantee the reduction of dust emission by 270 tons per year.
The new fibre filter will be in operation round-the-clock, as well as the previously installed facilities for the emissions reduction.