Corrosion is the main scourge of metal reinforced constructions and structures, steel machinery and metal products. Experts are constantly in search of ways to replace metal components with materials able to successfully resist corrosion, while being equally inexpensive, lightweight and easy to produce. Basalt fiber is increasingly considered a material of choice suitable to prevent corrosion due to its set of properties.
Experts estimate the damage caused by corrosion and the costs to prevent it in the stunning figures reaching 2- 6% of GDP in highly developed countries.
Academician Hou Baozhun, the scientific supervisor of the program ‘Corrosion issues in China and the strategic research of corrosion prevention’ estimated the damage caused by corrosion in China in 2014 at over 2.1 trillion yuan that is about 3.34% of that year’s GDP.
According to the latest data unveiled by the international professional association for corrosion control, NACE International, the US lost $ 276 billion (3.1% of GDP for the year of the study), because of corrosion effects and measures to reduce corrosion impact. For comparison, Germany lost 2.8% of GDP.
Corrosion annually “eats” 12% of the total metal fund in Russia so in 2014 it destroyed about 10 million tons of steel. The number exceeds $ 4 billion if expressed in monetary terms.
Corrosion does not only cause economic damage but also threatens people’s health and lives. Collapsed bridges, tunnels, and buildings, destroyed transport infrastructure of ports, and airfields, damaged chemical or nuclear facilities often lead to casualties.
Corrosion control involves a whole range of measures such as a replacement of corrosion-prone materials with those resistant to aggressive media. From this perspective, artificial inorganic fibers including glass, carbon, basalt, quartz, aramid, etc. demonstrate excellent results. However, some fiber types cannot find wide application because of either high production cost or insufficient resistance to aggressive media.
Compared to other fiber types, the functionality of basalt fiber attracts the constant interest of specialists, who highly evaluate its potential for the commercial application. Contemporary technologies have considerably reduced basalt fiber cost to almost glass fiber level, and basalt fiber properties offer benefits over glass fiber.
Basalt fiber is produced from a single component raw material, which is a product of volcanic activity and can be found in a huge amount on the Earth.
Molten in the volcanic chimney, basalt offers high chemical and thermal stability, which the fiber retains. There is no need to use complex technological machinery because the final product is manufactured in a single stage technology: basalt rock is melted, followed by either extrusion through the nozzles to produce continuous basalt fiber or blowing up to make discrete fiber.
Basalt fiber is highly resistant to the impact of water, acids and alkalis, it offers excellent physical and mechanical properties, and it is also fire-proof and non-magnetic material. Scientific laboratories of the world’s leading universities and private companies carry out studies on the application of basalt fiber as a reinforcement material in various matrix types. Basalt fibers have excellent adhesive properties, being compatible with various binders, both plastics and cement (the cement hardening setting is known to have an alkaline character), they can find various applications.
Lab experiments prove that basalt fiber reinforced concrete structures or basalt plastics rebar demonstrate better tensile strength, durability and fire resistance. In addition, they are more lightweight than their counterparts reinforced with metal components.
The theories produced in labs often come to nothing, not being turned into reality. However, basalt fiber escaped this fate and has already been put into practice.
In 2014 Swedish marina builder SF Pontona launched a project Prodock that is a construction of module marine concrete pontoons reinforced with basalt fiber. The company sees a huge market in Scandinavia, where many pontoons built in the 70s and 80s have to be replaced. Long service life, light weight, strength, sustainability and affordable cost, all those are aspects that Swedish manufacturers count on.
The Institut für Textiltechnik (ITA) of RWTH Aachen University actively develops new commercial solutions based on basalt fiber application. The BasFlair project (basalt fiber reinforced concrete) has been recently recognized part of Klima Expo, German climatic initiative, and is positioned as a project focused on climate protection through energy saving and reducing CO₂ emissions.
Another benefit that textile concrete offers is anti-corrosion resistance and higher plasticity than conventional reinforced concrete. Replacement of carbon fibers with basalt fibers can significantly enhance the application fields of the innovative composite material, says Andreas Koch, Head of the Department of Textile Construction at ITA. The main arguments are the low price and sustainability which result from the use of a renewable material.
Basalt rebar makes it possible to construct durable and resistant to corrosive environment floating foundations suitable for deep water wind parks. An example of a cost-effective durable floating foundation is placed on Windpower Engineering website.
Since all the structures are located in the corrosive marine environment, this aspect dictates high strength requirements for the materials. Traditionally, steel structures or steel reinforced concrete are used. However, other innovative technologies such as geopolymer cement with basalt rebar (GCBR) increasingly find their application in marine structures.
It is a spar buoy concrete floater with GCBR (basalt reinforced geopolymer concrete). The structure is assembled on a large Ocean Going Deck Barge (OGDB) tied to the quay in the harbor, and commissioned, ready for mating with the substructure at sea.
Basalt fiber mesh was used to strengthen concrete-clad spans in the rehabilitation of the Merrick Creek Bridge over the Detroit River. According to David Lawn, president for MEDA Engineering and Technical Services, company participating in the project, the new material is stronger and lasts longer than the carbon fibre reinforced counterparts. Basalt fiber is also 30 to 40% cheaper than other currently used mineral fibers.
Over the past few years, the US has implemented several large projects using fiber reinforced polymer rebar. Basalt America is one of the famous American manufacturers of basalt fiber and basalt products. Basalt America’s new projects include the City of Miami’s Omni Park (some structures in the park built using basalt mesh and basalt textile), the Halls River Bridge that is a vehicular bridge built with basalt rebar, etc.
Continental has introduced a modular system with basalt fiber for a textile line of conveyor belting ContiFlex Vulkan. It is designed to convey materials with temperatures of up to 1,000 degrees (F). These belts are applied in the cement industry, steel manufacturing, iron works, refineries, chemicals and fertilizer production. This line also can be customized to meet specific requirements, especially when it comes to conveying some of the hottest and harshest materials.
Germany-located Peterseim Strickwaren produces insulating basalt fiber fabric that can be used to protect maritime systems, such as buoys and other water-located structures. This fabric received a prestige Techtextil Innovation Award 2017 in the ‘new application’ category. Techtextil Innovation Award is held as part of Techtextil’s annual exhibition of technical textiles and nonwovens. Peterseim Strickwaren has broad know-how in advanced knitting techniques and can process a diverse range of difficult materials. To develop a new insulation coating, the researchers used antibacterial, antimicrobial and strength properties of basalt fiber. This protection material applied to the maritime systems suffering from the corrosive environment can reduce maintenance costs by almost 40%, the developers stress.
During Techtextil 2017, hybrid mesh and textile produced by GKD were demonstrated among basalt-based solutions and technologies. KraussMaffei introduced iPul, a pultrusion machine at JEC World 2017 in Paris. Reinforcing fibers include basalt, glass, aramid and carbon placed in a matrix of epoxy or polyurethane resin. Specialists characterize pultrusion profiles, as products with a high volume content of reinforcing filler to provide high strength at low weight. According to the company, the construction industry and the wind energy sector will be the main consumers for the products with these properties because they are in need of effective corrosion resistance.
Russian customers use a stabilizing basalt fiber additive for asphalt concrete, called Stilobit, which is manufactured by the subsidiary company of ОАО Uralasbest. It extends a service life of road surface, makes it resistant to rutting, and prevents segregation of asphalt mixture. This additive was used for the construction of many roads in the Moscow and Leningrad regions, Avtodor toll motorways, the Olympic facilities in Sochi. It is exported to Kazakhstan and Belarus demonstrating the growing demand.
Galen produces a line of modern basalt-based composite materials for the industrial and civil construction, the electric power sector and the road industry. High-strength and corrosion-resistant rebar, mesh, dowels and flexible connections allow for a better quality of the objects under construction and equally make it possible to reduce construction cost.
In the future, basalt fiber application is forecasted to grow steadily, and its scope to be expanded. A consulting firm Research and Markets in its report “Global Basalt Fiber Market Analysis & Trends – Industry Forecast to 2025”, analyzing the market data for 2014-2016 makes a forecast that the Global basalt fiber market will reach $392.5 million by 2025. The market will grow with a CAGR of around 14.2% over the next decade.
Irina Karpeso Editor-in-chief, Basalt.Today
English translation Olga Yurchenko, Editor, Basalt.Today