CALDERYS Expertise in DRI
Calderys has been working for over 20 years with successful activity in the worldwide DRI (Direct Reduced Iron) industry, where we are considered as a reference supplier. Thanks to our recent acquisition of ACE Refractories, the Calderys group has obtained a vast amount of DRI knowledge and experience. Calderys India Refractories Ltd is the pioneer in India in providing world-class refractory products and services to the DRI plants, both coal and gas-based. In India, Calderys has succeeded in converting almost 100 % from Brick to Castable lining of rotary kiln. Thanks to close partnerships with our customers, our solutions contribute to increased productivity and quality in the DRI making processes and also help to meet reliability and safety requirements.
DRI is the name commonly given to describe pellets, hot briquetted iron, lumps, and iron carbide. The advantage of DRI is it is an iron source with compositional uniformity and is virtually free from tramp elements. It is used increasingly in electric furnace steel making. DRI competes with higher grades of scrap in steel making and thus enables the use of lower quality scrap. In a direct reduction process, iron oxide pellets and/or lump iron ore are reduced by a reducing gas.
This can be done either in a gas based shaft or fluidised bed process or in a coal-fined kiln process.
In the Rotary Kiln business it is important to identify the refractory properties which need to be optimized to create optimal operating conditions for the customer. Rotary Kiln Refractories suffer from various stresses such as CO corrosion, accretion build-up, thermal spalling, and abrasion. Our aim is to provide solutions to our customers that combat the effects of abrasion and thermal shock, and accretion but also have a low porosity which minimize liquid penetration. We have developed a specific product range for the indian makrket for application in the rotary kiln, ACCMON DRI RZ. The abrasion, thermal shock, and impact, and corrosion resistance of ACCMON DRI RZ is excellent. The major advantage of this castable lining over bricks is the poor adherence of accretion on the refractory surface. It has also been observed that customized castable formulations yield better formulation compared to bricks usually in use.
DRI manufacturers are increasingly looking for longer campaign life and a reduction in downtime between operational processes. To address this issue, we have introduced a refractory maintenance lining for the indian market, ACCMON GUN DRI, a low-cement gunning material designed specifically for rotary kilns. This unique concept aims at minimizing the time taken for refractory repair during shutdowns. The low-cement gunning material bears the features of fast setting, low lime content, higher density, lower porosity, and high strength. This product was specially designed for fast application and excellent adhesion to old eroded lining. Because of its excellent hot properties, a repair with ACCMON GUN DRI also extends the life of the remaining castable linings.
Dust Settling Chambers (DSC) and After Burning Chambers (ABC)
Operations in DSC and ABC are typically less severe and require a different set of product specifications. In DSC, abrasion is the primary cause of wear and CO corrosion is also an issue. For ABC, thermal shock can be a danger due to the variability of combustibles present in the exhaust gas. Traditionally, OEMs for both chambers were suggesting brick solutions along with insulating bricks as back up. Calderys has substituted these products with a low/medium cement castable lining and Calcium Silicate board as back up. The refractory life, for both bricks and castables, in DSC and ABC exceeds 7 years. Comparatively, however, the castable has a lower thermal conductivity and leads to heat energy savings for the customer—this being one of their main performance criteria. Our refractory design for castables in DSC and ABC typically result in approximately 20% lower heat loss compared to that of brick based lining.
Well aware of refractory and DRI processes, our experienced supervisors and installers provide expert technical guidance and the best suited installation equipment to ensure the refractory performance during service.
Calderys employs dedicated skilled staff and the latest advances in refractory installation equipment. This can be applied to small, large, and turnkey projects alike depending on the requirement. Alternatively, we can support the customer's own staff by supervision, project management, equipment, and also direct installation training.
Our aim is to ensure the best installation and dry-out of the refractory so that the customer gets maximum performance.
Once in service, the refractory may require specific maintenance which again can be supplied depending on the customer needs. Depending on the situation, services are available on 24 hours per day, 7 days per week, ensuring minimum downtime for the customer—especially for unplanned emergencies.
Our engineering teams, dedicated to the D.R.I, help customers meet a wide range of requests such as: refractory lining design, heat transfer calculation, quotation, planning, installation and dry-out.
Calderys is often invited to take part in the development of a technical solution. Familiar with the specific processes of each type of units, we are able to engineer a refractory solution, provide project management services, and advise on the proper installation techniques for new projects. We have an excellent reputation for providing reliable solutions and thus have created many long-lasting relationships with our customers, end users, and engineering companies which have praised our products. Our strategic partnerships with the customers ensure that we develop market-oriented solutions. Due to our 100 years of experience, Calderys has the capability to become the integrated refractory partner and meet all the needs from solution design to implementation.