Generales

By Andrea Carolina Vargas Malagón, Journalist

After over 9 years of research, the members of the Chemical and Industrial Processes group (PQI), affiliated with Universidad de Antioquia’s Faculty of Engineering, in collaboration with Cementos Argos, have conducted a thermochemical process to produce biocrude from microalgae biomass. This technological development has been granted a patent in the United States.

The microalgae species employed in the hydrothermal liquefaction process for biocrude production capture 300 tons of CO2 per hectare per year.  Photo: UdeA Communications Office / Alejandra Uribe F.

The commitment to achieve a carbon emissions-free world by 2050 is a global undertaking under the Paris Agreement, aimed at mitigating the impacts of climate change. This pact compels all actors to seek alternatives for decarbonizing the atmosphere while minimizing the adverse effects on productivity. In other words, the objective is to transition to a sustainable decarbonized economy. 

This is where the “Hydrothermal Liquefaction of Microalgae with High CO2 Capture,” a technological development by UdeA’s Chemical and Industrial Processes research group (PQI), supported by Cementos Argos, becomes significant. It presents an economically viable alternative that aids in reducing carbon dioxide (CO2) emissions from the cement industry and paves the way for obtaining biofuels that could replace fossil fuels in the future.

This invention, which was granted the patent Solvothermal Liquefaction Process from Biomass for Biocrude Production Usp2022/000022 in late 2023 by the United States Patent and Trademark Office (USPTO), enables “the use of biomass generated by microalgae that capture CO2 emitted during the cement manufacturing process. This process results in the creation of a biocrude oil with properties similar to petroleum, which can subsequently be utilized in the production of liquid biofuels such as diesel, and gasoline” [FM1]  elaborated David Ocampo, a doctor in Environmental Engineering, member of the PQI and leader of the research.

Obtaining this patent demonstrates the maturity of the technology developed by UdeA researchers and marks significant progress towards its application in industry. “This document grants the University patrimonial rights over the technology and enhances its value during potential commercial negotiations,” added Ocampo.

Gabriel Jaime Vargas, Cementos Argos’ research and development leader, said that the collaboration with PQI contributes to the company's objective of bringing carbon-neutral concrete to the market by 2050. “The granting of the patent in the United States is an indication that we are moving in the right direction and serves as significant encouragement to persist with this important breakthrough,” Vargas said.

The Paris Agreement is an international treaty signed on December 12, 2015, though which, as of today, 194 countries commit to take action to limit global warming to below 2 °C compared to pre-industrial levels, that is the global temperature before the Industrial Revolution.

Capturing carbon dioxide as a first step, and then what?

According to the Global [FM2] Cement and Concrete Association (GCCA), cement ranks as the second most consumed substance by humans after water. Figures from the International Energy Agency (IEA) indicate that the cement industry is responsible for around 8% of the global CO2 emissions, as the production of this colorless and odorless gas is inevitable in the manufacture of this material. 

“The chemical reaction involved in cement production is an oxidation of calcium carbonate, inevitably leading to the emission of carbon dioxide. The chemistry of cement is not going to change, so cement companies are looking for alternatives to mitigate the environmental impact of their industry,” said Ocampo.

In the case of Cementos Argos, the first step taken towards reducing carbon emissions was the alliance with Universidad Eafit. This collaboration led to the development of a technology that uses microalgae to capture carbon dioxide. However, since the metabolism of these unicellular organisms is similar to that of any plant, they grow as they absorb carbon dioxide. Consequently, a new challenge emerged: What should be done with this growing plant material?

“Microalgae capture carbon dioxide obtained from industrial waste gases derived from cement calcination, release oxygen and grow, that is, they generate more microalgae.” Gabriel Jaime Vargas, research and development leader at Cementos Argos.

Cementos Argos became interested in the research that PQI was already conducting on hydrothermal liquefaction of biomass once the members of the research group evaluated the microalgae produced by the cement plant and found in them the potential for transformation into biocrude.

“The manufacture of this element becomes even more relevant as it has properties that allow it to use the current oil refining infrastructure to obtain the final fuels,” said Ocampo.

How is biocrude obtained?

One ton of CO2 is equivalent to 2.4 barrels of renewable fuel. Photo: David Ocampo

Petroleum, as it is known today, is the product of a process that took several million years, during which plant material and organic matter were buried and transformed into crude oil. According to Ocampo, hydrothermal liquefaction replicates this natural phenomenon. “It is a thermochemical process that subjects microalgae to high temperatures and pressure, transforming them into a biocrude oil within minutes, which can then be converted into somefinal fuel," the researcher explained.

Although the technological development was initially focused on utilizing microalgae, the research leader explained that this technology could be adapted to the use of other organic wastes. “Hydrothermal liquefaction could also be applied to agro-industrial wastes, such as those obtained from coffee production, banana residues or foliage material,” said Ocampo.

From pilot system to pre-commercial plant

After developing the technology and testing its operation with a pilot hydrothermal liquefaction system, the focus is now on scaling up the project. This involves the construction of a pre-commercial hydrothermal liquefaction plant at one of Cementos Argos' cement plants, located in Cartagena. At this location, systems are already in place to produce microalgae, which will later be transformed to produce biocrude from the actual emissions of the cement industry.

"The purpose is to obtain the biocrude in a real environment, to be later incorporated in co-processing procedures with conventional crude oil by Ecopetrol at the facilities of the Colombian Petroleum Institute. This initiative falls under the Pre-commercial Biofactory for Obtaining Microalgae Bioproducts research program derived from the increase in value of CO2 from industrial sources, financed by Minciencias,” explained the researcher.

With the participation of Ecopetrol and Minciencias, the University-Business-State triad is complete, in a project that paves the way for a sustainable business model that shows it is possible to promote carbon-free economic development to care for the planet. 

“Cementos Argos needs to capture the CO2, Ecopetrol will give the biocrude produced its final use and UdeA will oversee the technology and knowledge transfer phase to make it all possible,” concluded Ocampo.