For this area of application, CALCINOR mainly supplies sintered dolomite. This product is one of the various raw materials used in the manufacture of refractory bricks used in the kilns of steelworks, cement plants, etc. Since 2001, CALCINOR has been diversifying its activities thanks to the incorporation of REFRACTARIOS KELSEN in the group, which in addition to raw materials offers basic and non-basic refractory bricks used in both oxygen steelworks and electrical steelworks, in both current versions (alternate or continuous).

Activity:

The activities of REFRACTARIOS KELSEN focus exclusively on the iron and steel industry.
With regard to oxygen steelworks, the products from the REFRACTARIOS KELSEN range are destined for cladding working areas and safety in the converters, casting ladles and ladle-kilns, mixing troughs and also the torpedo ladles for transporting pig iron.
With regard to electrical steelworks, in its two versions of alternate and continuous currents, the refractory materials produced by REFRACTARIOS KELSEN are used in the kiln, the ladle-kiln and the mixing troughs. In the specific case of the manufacture of stainless steel, the refractory bricks made are used in the AOD converter and the transport ladles.

Up until the 1980s, the production of refractory bricks was aimed exclusively at the domestic market. In 1985 there was a real transformation for REFRACTARIOS KELSEN, as this year saw the start of exports of their refractory products. By 2002, REFRACTARIOS KELSEN was supplying a network of more than 60 clients across over 20 countries (South-East Asia, Germany, France, Belgium, Italy, the Middle East, Mexico, North Africa, etc.).
The main objective of REFRACTARIOS KELSEN is to become established as a major benchmark in the refractory market, and to do so the company is immersed in a dynamic process of modernising its production facilities to improve both the quality and range of its manufactured products and its production capacity through the automation of installations. In 2004, considerable investments were made in installations geared towards manufacturing tempered products which will allow REFRACTARIOS KELSEN to gain access to markets with stringent environmental restrictions. In this way, markets that were previously inaccessible, such as the United States, the United Kingdom, South Africa, Scandinavia, etc., are now open to our new manufacturing programmes, notable amongst which is the extensive range of dolomite refractories for use in the production of special steels and stainless steels.

Facilities:

The production process starts with checking the raw materials necessary for manufacturing the products, verifying their compliance with the required specifications for materials both from our own resources (high-quality, high-density and high resistance to hydration sintered dolomite manufactured by CALCINOR at its Bueras plant) and from others (magnesites, olivines, graphites, bauxites, corundums, calcined clays, silicas, zirconium silicates, cements, pitch and tar, resins and other additives).
After this initial quality control check, the raw materials received in bulk are sent for grinding and sieving by means of separate grinding lines, thus avoiding any potential cross-contamination. The raw materials that do not need grinding, together with those that are already ground and classified, are sent to the relevant dosing silos. During this process, the necessary quality controls are undertaken to ensure the correct gradations established for each silo.
The process continues with automatic metering and mixing of the different components (aggregates, binders and additives) in independent weighing lines with various mixers which allows a wide range of products to be produced, whether shaped or non-shaped, basic (Dolomite and Magnesite) or non-basic (silica, zircon, alumina), and agglomerates such as pitch with resins and acids.
For shaped products, the process continues with the pressing of the previously mixed mass. To do so, we have five hydraulic presses equipped with robots to avoid handling the bricks. At the bottom of the press, dimensional and density controls are carried out to ensure the press is operating properly (both manual and automatic).
If necessary, the process continues with the curing or tempering of the bricks in a modern tempering kiln that allows the volatile elements from the binders used in the pressing process to be incinerated, thus avoiding the problem of emitting them into the atmosphere of the steelworks during their pre-heating process.
Once the bricks are completed, they are palletised by robots and automatically packaged and labelled on the packing line, with samples for laboratory analysis being taken prior to their dispatch.

Customer service: Engineering and technical services

At REFRACTARIOS KELSEN we are aware of our great responsibility for the refractory materials used in the iron and steel industry. REFRACTARIOS KELSEN understands quality as making sure its products meet the operating conditions of each of its clients. Risk reduction and optimisation of cladding costs require constant liaison with our clients to ensure that our products are perfectly adapted to the various manufacturing processes.
This personalised attention starts with a study of the client’s manufacturing process and continues with the design of the most suitable cladding, the selection of the ideal characteristics and formats to present the offer, supervision of the assembly and putting into operation of the refractory, and finalises with a study of the residual thicknesses that will allow us to define any improvements.
To do so, we have a team of specialists in both refractories and the steel manufacturing process who are capable of compiling the technical information necessary to ensure our products meet the variable needs of our clients and that it is reflected in the corresponding plans.