Sequestering & Monetizing Carbon Dioxide: Critical To The Economic Health Of Chemical And Energy Projects, And The Well Being Of Our Planet

By Sam A. Rushing, President, Advanced Cryogenics, Ltd.
Special to The Digest

With respect to all options being essential, we can start with sequestering CO2 via the best farming methods, and enhancing closed greenhouse operations with CO2 to put photosynthesis in overdrive. With respect to carbon management for farmers, climate smart practices do enhance CO2 sequestration in the soil and plant biomass, such as cover cropping, reducing tillage, agroforestry and rotational grazing. Such practices contribute to building soil organic matter and storing carbon. Such techniques are accomplished in this brief summary.

I. NASCENT, PASSIVE, AND LESS INTRUSIVE TO THE ENVIRONMENT

1. Cover crops are non-cash crops planted to protect the soil during off-season periods, or when no main crop is growing. Such stops soil erosion, and improves organic matter content, thus contributing to carbon sequestration.
2. Reducing tillage reduces the disturbance of the soil, and maintains soil structure and the important organic matter.
3. Agroforestry represents planting trees along and into crops and pastures; thus creating the sponge effect of CO2 sequestration by trees, via photosynthesis.
4. Rotating grazing is critical to soil health and organic crop sequestration, allowing pastures to recover and regrow, this enhancing soil sequestration of carbon.
5. Then we can think about adding biochar to soil, thus optimizing soil sequestration. Further, avoiding deforestation, and conservation of wetlands represent carbon storage.

Climate friendly farming

Next, there are all the techniques defined and being improved upon, and developed, which in many cases sequester CO2 in one form or another; at least to a degree. Such examples are defined.

1. DAC, or direct air capture; essentially taking a vacuum to the air; where this is an expensive means of trying to reduce CO2 content in the atmosphere; albeit there is some value in reduction.
2. Enhancing Weathering, via crushing and spreading rocks on land to accelerate the natural process of a reaction to CO2, creating stable carbonate compounds; this is in some cases an emerging technology.
3. Carbon Mineralization, such is injecting recovered CO2 into specific rock formations, thus forming solid carbonate minerals; toward permanent sequestration of CO2.
4. Ocean alkalinity Enhancement, this involves seawater to capture and store CO2; such as via introducing alkaline minerals and electrochemical means.
5. Seawater Farming and Sinking, via growing and sinking seaweed in the deep ocean; such would potentially store carbon for centuries.

II. TRADITIONAL CO2 RECOVERY, LIQUEFACTION, PURIFICATION FOR INDUSTRY, PIPELINE DELIVERED TO SEQUESTRATION AND EOR

For the approximate 111 merchant CO2 projects, plus many EOR projects, and planned sequestration ventures, liquefaction/purification is a standard. For virtually all the merchant sources from largely ethanol, ammonia, reformers, natural, and other chemical sources, when directed to a 10 million TPY merchant demand, beverage grade is the standard. Otherwise, when going to pipelines, there is a standard quality requirement such as to EOR destinations requiring low oxygen and water content; thus retarding mold and rust.

CO2 plant nearby ethanol facility – traditional liquefaction/purification plant

From enriched raw gas sources such as ethanol, & ammonia, the raw CO2 content is often greater than 99% in a raw gas upstream of purifying and liquefying the product for the merchant sector; v. the passive, DAC, photosynthesis and like destinations, the CO2 content is very low, typically atmospheric, now over 417 ppm, by many estimates.

Cryogenically frozen berries

SUMMARY

Therefore, when considering the all – important methods of sequestering, monetizing and ultimately reducing CO2 emissions, all forms are equally important, from caring for planted crops, soil care, carbon mineralization; to direct CO2 recovery from enhanced streams like ethanol & ammonia.  All this represents value, whether generating revenues (from the merchant markets, tax credits), to  reducing emissions via storing the CO2 in rocks, trees, and plants.

It is ever more critically important to recover, utilize, and sequester carbon whenever possible. Even when sold in the markets to carbonate beverages, freeze food products; or blast clean surfaces with ¼” dry ice pellets, all represents revenues from such applications in industry – even though many merchant uses are simply recycling CO2 in a form. However, many merchant uses actually sequester the product such as in greenhouse (plant) enrichment, and concrete enhancement.

Let’s try to maximize the monetary value of CO2; and sequester however possible; and help save our planet.

About the author

Sam A. Rushing is president of Advanced Cryogenics, Ltd., a major CO2 consulting firm providing all forms of consulting expertise, covering all technical through market and business related work for over 30 years throughout the Americas and globally. Tel. 305 852 2597, rushing@terranova.net, CO2consultant.us