From waste to new steel: Univalle researchers test a novel recycled material

Researchers from the Universidad del Valle, an international company and other Colombian researchers have collaborated to convert a waste product from the metal-mechanical industry into a steel that is of good quality, resistant and affordable.

The global metal-mechanic industry generates some 13.5 million tons of a waste known as mill scale, according to 2008 statistics, and still in Colombia many companies allocate economic resources for the correct disposal of this type of by-product, which leads to a decrease in their productive and economic efficiency.

Therefore, since 2019, three partners have worked on a new material: researchers Escuela Colombiana de Ingeniería Julio Garavito used mill scale from Gerdau-Diaco (An international company with a brnach in Colombia); and reserachers from the School of Materials Engineering (EIMAT) of the Faculty of Engineering of Univalle in Cali, Colombia did tribological trials on the new material.

In the paper “The high temperature tribological behavior of an iron oxide strengthened iron compound obtained from an industrial byproduct," published in the scientific journal Tribology International in August 2022, the researchers showed that the mechanical and tribological properties of this recycled material are very similar to conventional steels that are already available on the commercial market, and that this new recycled material can be an alternative to these steels.

"We want to change from a linear economy to a circular economy and that entails the reuse of all industrial by-products that can be generated in the production processes of both national and international industry," Professor Christian Ortiz Ortiz, PhD student and assistant professor at Univalle's School of Materials Engineering said.

Photo: Christian Ortiz Ortiz, PhD student and assistant professor at Univalle. Credit: Andrew James/NCC-FI/Univalle

The Research

Researchers used previous work in this field to find new processes and new materials.

But before these new materials can be brought to market, they must be synthesized and then tested to ensure that the recycled material has the same mechanical and tribological properties as conventional steel.

Ortiz, working under the supervision of Dr. Julio Cesar Caicedo Angulo, PhD, in the Tribology, Polymers, Powder Metallurgy and Solid Waste Transformations Group – TPMR led by Yesid Aguilar) was able to advise the material produced by the Colombian School of Engineering Julio Garavito in Bogota at the Gerdau-Diaco facilities. Professor Ortiz, explained that the general applications of the new steel material are structural (withstand a large applied external load) and also that it withstands aggressive environments, such as high friction at high temperatures.

"But the main thing, is that this material supports a state of load in the face of high friction, the main application, is that this material can replace conventional steels which are exposed to direct contact with other steels or other materials," said Professor Ortiz.

The researchers noted that the material is important from the point of view of the circular economy, because the idea is to return the material to the productive chain, and give a value to a by-product that currently has none.

"Not only is this iron oxide a waste, but companies have to pay for the correct disposal, and this cannot happen if we want our industry to be able to compete with other international industries, so you need to increase productive efficiency in every aspect of the industrial processes," Professor Ortiz said.

Read more: From Plaintains to Plastic: Agricultural Waste Turns Into Compostable Polymers 

Image: SEM micrographs of the wear track of the new material at room temperature. Credit: Christian Ortiz Ortiz

Colombian Collaboration

Adriana Esguerra Arce, a professor at the Colombian School of Engineering Julio Garavito in Bogota said that the article was the result of a research project funded internally by both the Colombian School of Engineering Julio Garavito, and the Federal Polytechnic School of Lausanne, in Switzerland,

"The material was generated at the School, using calamine from Gerdau-Diaco, which is one of the main steel mills in Colombia,"professor Arce said, adding that the motivation was to give added value to this industrial by-product that, today is exported to countries such as China.

"We cooperated with these two universities because of their strengths in materials characterization," Professor Arce said, adding that Professor Yesid Aguilar was her and her sister Johanna Esguerra's doctoral thesis director.

"Regarding Christian Ortiz, he is currently a doctoral student of Professor Julio Cesar Caicedo, so he was his collaborator in the experimental part of the tribological measurements," Professor Arce said.

Professor Arce explained that there were many advantages for the Colombian School of Engineering Julio Garavito and Universidad del Valle to collaborate on this project.

"The main impact for both institutions is the strengthening of research capacity, the training of research personnel, and the visibility for research products such as the research article," Professor Arce said.

If you would like to contact the researcher or learn more about the project, please write to the Communications Office, Faculty of Engineering: comunicaingenieria(at)correounivalle.edu.co.

Cover photo: Christian Ortiz Ortiz, PhD researcher and assistant professor at Univalle, (left), with supervisor Professor Julio Cesar Caicedo. Credit: Andrew James/NCC-FI/Univalle

Nota Aclaratoria: 

DIRECTOR DEL PROYECTO EN UNIVALLE : PROFESOR TITULAR YESID AGUILAR CASTRO

DIRECTOR DEL PROYECTO EN LA ECI : PROFESORA  Adriana Esguerra Arce

ESTUDIANTES Y PROFESORES QUE PARTICIPARON EN EL PROYECTO :   De la Escuela Colombiana de Ingeniería JULIO GARAVITO  ECI el grupo CIMSER  

Doctoras Johanna Esguerra Arce, Adriana Esguerra Arce, Ángela Bermúdez Y LOS ESTUDIANTES DE PREGRADO Tatiana Reyes Segura y Johanna Gisell Tirado

De la universidad del Valle TPMR, Participante YESID AGUILAR CASTRO

De la Ecole Politechnique Federale de Lausanne groupe de Tribologie et Chimiedes Interfaces, participante Dr.Stefano Mischler 

LA EMPRESA DIACO 

También se aclara que el señor Christian Ortiz Ortiz es Asistente de Docencia.