We visited the Kaolines Beneficiation Plant of the company Minerales Industriales, which is located in La Unión, Antioquia, Colombia, to learn about its operation.
by Duván Chaverra Agudelo
Kaolin is a hydrated aluminum silicate, product of the decomposition of feldspathic rocks, it is a very recognized material due to the different applications where it can be used, as is the case of paints.
In our industry it is mainly used as a titanium dioxide extender, its use has become popular due to the properties it offers to the paint such as its high coverage, improvement of rheology, washability, finishing among others. Kaolin is also used in other applications such as paper, ceramic pigments, refractories, rubber, construction, agrochemicals among others.
In Colombia there is a municipality belonging to the department of Antioquia called La Unión, one of the few places in Latin America where the raw material for the production of kaolin is found. There Minerales Industriales S.A. has two wet processing plants and five mines for kaolin extraction. Minerales Industriales S.A. is a Colombian company created in 1976 with the purpose of providing solutions to its customers in the field of non-metallic minerals. As of 2005, the company was mostly acquired by Sumicol S.A.
Sumicol is a manufacturing company dedicated to mining, the provision of industrial inputs, technical services and semi-finished products for various industries, mainly ceramics, glass, paint, paper and building.
Minerales Industriales has a wide portfolio of solutions in non-metallic minerals such as hydrated kaolins, calcined kaolins, talcs, micas, sands, clays, clays, feldspars, dolomites, atapulguitas and systems composed of non-metallic minerals for different industries.
The experience of the visit
INPRA LATINA visited the facilities to learn about its operation and observe the production process, delving into the benefit of non-metallic minerals for the manufacture of paints.
During the visit we had the opportunity to visit one of the extraction mines, the kaolin storage areas, equipment, laboratories and part of the personnel who work there.
The industrial minerals engineer, Gonzalo Franco Arroyave, who guided the tour of the facilities, explained in detail the process of kaolin generation from the mine to the final product.
"The process begins with the characterization of the mines to determine the type of existing material and its properties, then the exploitation and transfer to the plant where they are stored in warehouses is carried out. In the plant the material goes through a process of wet sorting, delamination and bleaching. The products resulting from these processes can be delivered in different presentations, in bulk suspension (Slurry) or in bags of 25 Kg or Big bags of dry product powder, semi-dry in chips or pre-dispersed in micro spheres.
In the middle of the above process, different controls are carried out so that the product meets the required specifications. On this aspect, Gonzalo said that "measurements of pH, viscosity, particle size distribution, color, percentage of retained, chemical composition by FRX, and mineralogical analysis by DRX are made."
The plant is very cautious in its work, and therefore each stage of the process has a laboratory (five in total) from the extraction of kaolin to the final product. It also has a central quality laboratory in the plant and an R&D laboratory located in Sabaneta Antioquia. Minerales Industriales S.A, have iso14001 and ISO 9001 certification in the exploration, exploitation, design, development, processing and marketing of non-metallic minerals for industrial applications.
An interesting fact about the operation of the Industrial Minerals plant is that its specialty is the production of formulated mixtures of non-metallic minerals, powder, pre-rough in suspension or dry pre-rough. These mixtures have the ability to replace all the pavers used in the formulation of paints and are ready to enter the stage of completion of the paint. Minerales Industriales has generic mixtures and mixtures designed to suit its customers that provide flexibility and efficiency in the paint manufacturing process, reducing process times, increasing productivity and guaranteeing the quality and stability of the final product.
As mentioned above, Minerales Industriales has five mines for the exploitation of kaolin for ceramics and paints and has an installed capacity to produce 1,700 tons per month of kaolin for paints. All mines have reserves estimated at 50 years and constantly conduct exploration to find new mineral deposits.
Regarding the process of evaluation and exploitation of deposits, Gonzalo explained that "these are evaluated with the performance variables expected by customers; the exploitation is designed maximizing the reserves to make a rational use of these natural resources. Minerales Industriales carries out activities and works of an environmental nature to minimize, control, mitigate and compensate for environmental impacts; complying with current regulations on both mining and environmental issues".
About the plant, engineer Franco added that "it has a staff of 48 people divided into 26 operators, 2 operations facilitators, 4 quality assistants, 4 logistics assistants, 1 operations administrator, 1 technical process engineer, 7 maintenance assistants, 1 S&SO facilitator, 1 maintenance coordinator, 1 mining zone coordinator and 1 secretary.
The commitment of Minerales Industriales with the sustainable development of society is carried out through a public-private partnership that contributes to the development of the Municipality of La Unión (Antioquia) on three fronts: Educational Infrastructure, Housing Infrastructure and educational quality. Favoring so far an average of a thousand people in the different programs.
Functions of kaolin in paints
Kaolin has been used for years in the elaboration of architectural paintings. Due to its size and laminar shape it offers greater dry and wet coating than other pavers, reducing the consumption of titanium dioxide, as well as greater flexibility to the film decreasing cracking. It also offers a smooth finish to the surface, preventing it from getting dirty easily and improving washability. Its chemical composition guarantees a high resistance to different chemical agents and offers great stability in terms of sedimentation. For long periods of storage it prevents the formation of hard sediments due to its suspension capacity. Additionally, its specific gravity lower than other pavers and pigment offers a higher performance in volume.
The presentations of dry and wet predisperse kaolin (Slurry) of Industrial Minerals favors the incorporation of these in the process of manufacturing paints and decreases the generation of particulate matter taking care of the health of the operators.
For INPRA LATINA it was a very enriching experience to have known the facilities and operation of a company such as Minerales Industriales, which for more than 37 years has been one of the most important players in the paint industry in Colombia.
