Water, carbon dioxide captured from car exhaust could help grow food

close up of car exhaust pipe

Texas A&M researchers are proposing a new way to reduce the environmental impact of common road traffic and increase resources for food production.


Getty Images

What if both the water and carbon dioxide (CO2) generated by a vehicle’s exhaust system could be captured and used to grow food? Reusing these two wasted products would be a game changer in reducing the carbon footprint of road traffic and helping the agriculture industry feed the growing human population.

Three faculty members from Texas A&M University, Maria Barrufet, Elena Castell-Pérez and Rosana Moreira, have written a white paper reporting their initial analysis and seeking the funding needed to conduct formal, multidisciplinary research on the project. Hopefully it is published.

“I started reading related literature and emulating what was possible,” said Baruffet, a professor and Baker Hughes Endowed Chair in the Harold Vance Department of Petroleum Engineering. “This is completely realistic. Many proposals have already been written for large truck and marine vehicle applications, but nothing has been implemented yet. And we are the first to think of a passenger car engine “

The impact can be huge. In 2019, the number of vehicles in use worldwide was 1.4 billion. An average passenger car in operation can emit about 5 US tons (about 4.6 metric tons) of CO2 per year, meaning a significant amount of the greenhouse gas is going into the environment. The fuel combustion of a car also creates a large amount of water per year – about 5,547 gallons (about 21,000 liters).

Castel-Pérez and Moreira, both professors in the Department of Biological and Agricultural Engineering, know that this wasted CO2 and water can be put to good use, especially in cities. Recent expansion in US urban agriculture has relied on industrial greenhouses, which use artificially enriched environments with up to three times the amount of CO2 in normal air to improve plant health and harvest. These urban farms would benefit greatly from a stable source of free, reclaimed CO2 and water as they currently purchase and use only about 5 pounds (over 2 kg) of CO2 and about six gallons (22 liters) of water for only two pounds. To grow more. 1 kg) yield. And these numbers do not include the water and CO2 needed for post-harvest food processing and dense-phase pasteurization.

Three faculty members outlined how the integrated tool might work. The heat from the engine can power an organic Rankine cycle (ORC) system, essentially a small, closed unit consisting of turbines, heat exchangers, condensers and a feed pump that acts like an old-fashioned steam engine. but on a much smaller scale, and at the same time very little heat is needed to generate electricity. ORC will power other components, such as a heat-exchange system, which can cool, compress and convert CO2 gas into a liquid for more compact storage.

“Years ago, we didn’t think we could have air conditioning in a car,” Baruffet said. “It’s the same concept as the air conditioning that we have now. Simply put, it’s like that device, it’ll fit in tight spaces.”

Initial simulations are encouraging. No significant reduction in the car’s engine power or an increase in its fuel usage is predicted. Any potential corrosion in the heat exchange system can be addressed with the use of new coating materials. Theoretically, vehicle owners could replace full cartridges of CO2 and water at correction centers, just as people bring aluminum and steel cans today. Or drivers may also use CO2 and water on their own or within a community greenhouse system, provided the CO2 is used responsibly and fully absorbed by plants.

However, questions remain about how big these cartridges need to be, how the water will be handled because it cannot be compressed, and at what weight the stored CO2 and water will affect the car’s performance.

Barrufet, Castell-Perez and Moreira are actively seeking funding to continue their work. While research is already underway in national laboratories and industries on improving equipment for large-scale CO2 capture, nothing currently exists on this small scale, so it could take 10 years before something is ready for testing. .

The biggest challenge may come from assembling a multidisciplinary team to conduct research. Components for the device already exist in some form or another, but redesigning them to work together in such a limited space would require a team of engineers of various specialties.

“All these independent ideas and technologies have no value if they cannot connect,” Buruffet said. “We need people concerned about the future so that it is soon, enthusiastic students in petroleum, mechanical, civil, agricultural and other engineering disciplines who can transcend boundaries and work in sync.”

nonton the naked director season 2

Leave a Comment