Kingfisher’s Wear Resistant Ceramic lining systems extend the lifetime of slag granulation components
Production of blast furnace generates large amounts of liquid slag and can be processed into valuable raw materials known as ground granulated blast furnace slag (GGBS). By installing wear protection systems within key components, it has proven to add longevity to equipment however many plant engineers invest in particular wear resistant system which in many cases is not fit for the process. Just to add, incorporating wear-resistant lining systems amongst steel or aggregate manufacturing processes is not an innovative or new solution, in fact, wear protection systems have been implemented within the bulk handling industry for many years. Tried, tested and trusted systems have proven ceramic lined components have shown to last much longer in-situ in comparison to refractory type or hardened steel systems, with the GGBS process.
Traditionally, metallic materials such as QT, and manganese plate and castings have been used as wear resistant solutions in various quarrying crushing operations, where the product is handled and crushed down to a minus-sized aggregate. As further processing is undertaken for sand and small aggregate, polymer type materials such as rubber and polyurethane operating in a hydraulic state have been used with great success. As with all solutions to problems, careful consideration has to be given in identifying what unique issues associated with grades and mineral types are prevalent, as a 'one size fits all' approach very rarely succeeds.
A large building product producer in Port Talbot utilise liquid slag and further create aggregate and building products for the construction industry. Kingfisher was visited by this client at Hillhead 2016, they had been using another supplier of wear systems, however, the system supplied was not offering the equipment longevity required.
Granulated slag can replace up to 70% of the more costly Portland clinker. However, slag volume depends on the quality of the raw materials used in the blast furnace and may range depending on production levels of a modern blast so the annual slag production could amount to more than 1Mt.
Efficient processing of blast furnace slag into a product suitable for further use is accomplished through a slag granulation plant. The main objective of the slag granulation plant is to process liquid blast furnace slag into valuable raw materials for the cement and construction industries. The value of the slag depends on its characteristics such as mineralogical, chemical, physical and mechanical properties, glass content, structure and moisture content. These technical properties are related to the blast furnace burden and process. The applied granulation technology and operating conditions, storage and dewatering time.
To extract iron from ore, it is necessary to purify the ore from foreign substances it holds and removes the oxygen inside the iron oxide by resolving it. In order to carry out these processes, iron ore is heated and melted at high temperatures in blast furnaces. With high temperatures in the furnace, residual molten iron, molten lime, silica, alumina, a slag composed of coking coal ash, and other foreign matters are generated while the carbon in the coking coal combines with the oxygen in the iron oxide and leaves the furnace as CO and CO2 gases. Molten slag, which is cooled down and granulated, is referred to as “ground granulated blast furnace slag”, it is through this purification phase, key components are subject to high levels of wear and abrasion.
Consuming a great amount of energy and emitting destructive greenhouse gases to the atmosphere during the production process, most of the binder materials have a significant role in environmental pollution. Therefore, binders utilise various mineral additives to reduce the CO2 emission and to increase the production rate, by reducing energy consumption. Granulated blast slag, which is one of those mineral additives, is formed during the production of pig iron in iron and steel factories and a major part of it is ready to be used as an alternative binding material.
Processing raw materials, with such strong foreign characteristics, has detrimental effects on the equipment used throughout its manufacturing process and this is where many manufacturers invest in the use of wear resistant lining systems to be incorporated within their components.
The use of industrial by-products, containing a high percentage of silica and alumina as additives in cement or is a convenient area for the utilisation of large volumes of waste materials.
Wear protection also lends itself to the repair process, as it offers the flexibility to be implemented at any time during the life of process plant and equipment. In addition, most equipment is designed to allow access for cleaning, repair or replacement, so as long as the substrate of the original equipment is not compromised through excessive wear or corrosion, then it can continually be repaired in-situ. Even if the substrate is compromised, then, by utilising Kingfisher's engineering operatives, be it on or off-site, it can be brought back to a suitable working condition for reuse by re-plating incorporating suitable surface preparation and protection. An additional benefit of repairing in situ is that it removes major requirements for expensive plant hire, including lifting equipment and specialist personnel to remove and replace.
Ideal components such as slow down boxes and distributor which are subject to handling slurries and highly contaminated material often experience increased levels of wear and abrasion.
John Connolly MD at Kingfisher stated “We have worked with both Steel manufacturing and Aggregate production facilities for over 40 years, offering a range of systems fit for the process, on many occasions we have offered.
Publish Date: 06/03/19