Conquid: Make the Grey Greener

Re-Inventing Concrete Production to Reduce Carbon Emissions

In the time you’ve read this sentence, 317 tons of concrete have been produced.

Current State of Concrete Production:

Concrete is the second-most widely used substance on the planet with 4.4 billion tons produced each year. The production of each ton of concrete emits 0.93 tons of carbon dioxide into the atmosphere. This results in 4 billion tons of carbon dioxide emissions each year solely due to concrete production, accounting for 9% of worldwide carbon emissions.

Accounting for 9% of global CO2 emissions, the concrete industry doubles those of flying or shipping.

Problem Areas and Causes

The majority of the emissions originate from the manufacturing process of cement, the main ingredient of concrete — more specifically, the calcination process of heating a limestone and clay mixture to 2500° Fahrenheit. Carbon dioxide emissions play a fundamental role in global warming and the greenhouse effect. Carbon dioxide emissions are not only increasing rapidly due to the unoptimized production process, but also because the demand for concrete continues to exist at a rate that renders this process incredibly harmful in the context of global warming. While it’s much more difficult to reduce carbon emissions as a whole, carbon capture in the cement production timeline is a very plausible opportunity to reduce the net carbon emissions. In fact, carbon can be utilized and stored inside of this concrete forever, preventing it from rel

Areas of Opportunity

During the production of concrete, cement is normally combined with water, its hydrating factor, in order to harden into its final form of concrete. This uses a 10th of the world’s industry of water in the process. However, liquid carbon dioxide has proven to be just as effective as wate with the added benefit of capturing and storing carbon within it and significantly reducing water usage worldwide. While the emissions of carbon dioxide from this production process aren’t necessarily reduced, the net negative implications of concrete production can be reduced by 5.5% per year — 244 million tons of carbon dioxide annually!easing into the atmosphere and contributing to global warming.

Current Initiatives

Various companies are working on the process of utilizing liquid carbon dioxide as the hydrating factor for turning cement into concrete as opposed to water. This allows concrete to store a certain amount of carbon dioxide to make significant impacts at a large scale in the amount of carbon dioxide emitted from the concrete production process.

CarbiCrete — A cement-free, carbon-negative concrete alternative. Easily implementable in precast concrete plants, where cement is replaced by steel slag (an industrial byproduct). Lower material costs, faster to harden, greater strength.

CarbonCure — Injects captured CO2 from the air to permanently store in concrete. They source CO2 from industrial gas suppliers, which is injected into wet concrete during the mixing process. The CO2 undergoes a mineralization process that strengthens the concrete while reducing cement needed.

Why Hasn’t the Problem Already Been Solved

Certain companies are working on utilizing liquid carbon dioxide as opposed to water in the concrete production pipeline. That being said, they’re unable to scale this to a point where its impacts are significant. The energy consumption for acquiring liquid carbon dioxide is incredibly high and unoptimized. Carbon dioxide can’t simply turn into liquid carbon dioxide through cooling. It is required to be compressed in high pressures and further cooled into its liquid state. While there are major benefits in regards to reducing carbon dioxide in our atmosphere, there’s very little insensitive to actively utilize liquid carbon dioxide as opposed to water, a common natural resource with a much lower price, leading us to our biggest issue: cost.

Companies interested in producing concrete much prefer using water due to its low costs and easy acecssibility. Liquid carbon is much more difficult to produce, transport, and store, due to its particular storage requirements and high energy usage during production. While there is general insentive for reducing carbon emissions with carbon taxes and government subsidies, there isn’t enough to merit the significant increase in concrete production costs that the status quo entails.

The Time is Now

With the Paris Agreement aiming to limit global carbon emissions to a maximum of 1.5° Celsius, now more than ever it is needed to invest in carbon capture, use, and storage in order to further reduce costs and incentivize costs over time. With carbon-treated concrete developments over the next ten years, we hope to get 70% of future concrete to be carbon based as opposed to water.

Introducing CONQUID

Conquid reconstructs the production pipeline of concrete entirely with a centralized production approach. This takes down the cost barrier attributed with using liquid carbon dioxide as opposed to water during the concrete production process by removing the necessity of storage and transportation of liquid carbon. Carbon dioxide is turned to liquid in the same facilities in which this liquid carbon will be fed into concrete. Conquid proposes a solution in which both gas compression and concrete production are done together. With the temperature conditions and pressure requirements taken into account, carbon dioxide is fed into a gas compression pipeline and converted into the liquid form of carbon dioxide. This liquid carbon is then injected into the concrete mix, reacting with calcium ions from cement to form the nano-sized mineral Calcium Carbonate. This ultimately results in the initial carbon being completely trapped within this concrete.

What is the Outcome of the Solution

With this omni-channel model for concrete production, Conquid reduces all cost barriers associated with the transportation and storage of liquid carbon. Carbon-based concrete still requires various costs such as the cost of the carbon dioxide, the gas compressors required for convertin gaseous carbon dioxide to liquid carbon dioxide, and the energy required for this state conversion process. That being said, this carbon-based concrete solution results in a 5.5% decrease in carbon emissions related to the production of concrete. This equates to a 244 million ton decrease in worldwide carbon emissions, an almost 0.7% decrease of overall global carbon emissions. With Conquid, these results are achieved with only a 9% increase in annual concrete production costs.

In the time you’ve been reading this, 76,104 tons of concrete have been produced.

Every year that goes by with unoptimized concrete production, over 240 million tons of carbon dioxide are released into the air — 240 million tons of carbon dioxide that don’t need to be there. With Conquid, these outcomes believed to be only possible on paper can truly become a reality.