Carbon DIoxide, CO2, or Super-Gas?

SYOXSA, Inc. is a trusted supplier of carbon dioxide to El Paso and surrounding areas.

The majority of people not affiliated with the industrial gas industry recognize carbon dioxide, CO2, as the gas used to carbonate soft drinks and as the chemical in fire extinguishers. CO2 is used in more forms than any other gas in the industrial gas market making it one of the most versatile products sold

Brief History

In the early 1600’s, Jan Baptista von Helmont, a Finnish scientist, discovered CO2 as the gas that resulted from burning wood. In the mid 1700’s Joseph Priestly, an English chemist, found that mixing water and CO2 being expended from a fermentation process created sparkling water which altered the water’s taste and was the driving force behind the start of the soft drink industry.

One of the attributes of the gas that was found was its ability to be easily liquefied. This resulted in it becoming the first commercial industrial gas to be offered as a packaged gas. Eventually, after learning more about the gas, CO2 became the only gas sold and employed in all three of its phases – gas, liquid and solid.

Gas

CO2 is most often associated by those in the gas industry with the food and beverage industry for its use as a refrigerant or as a shielding gas in welding. There are also additional unique properties of CO2 that contribute to its versatility .

The most fitting example is when after making contact with water, CO2 forms carbonic acid. Although it is a weak acid, it is an acid nonetheless and is employed to regulate the pH in some cases where the pH is an important system parameter. This is prominent in different industries such as paper production, textiles, and water treatment processes. An additional benefit is that carbonic acid is not stored as an acid (such as sulfuric or hydrochloric acids). As mentioned, the CO2 requires water to create the acid so it remains CO2 until needed and unlike many other acids, is not considered harmful.

Liquid

CO2 is stored as a liquid regardless of the container. The pressure in an uninsulated CO2 cylinder is usually around 800 psig depending on the atmospheric temperature. The outcome of this is that any process using liquid CO2 should be under pressure. Employees in the oil industry are aware that CO2 takes the place of water in enhanced oil recovery (EOR) where the liquid is combined with sand or sand like substance (proppant) and sent down an oil well to recover oil that is trapped inside the rock layers. EOR is a general term that can apply to a variety of procedures but the most prominent is fracking. Here man made fissures are used to pump the propant into rocks that are rich in oil. As a result, the rock fractures and the trapped oil is released. When CO2 is used instead of water, its natural expansion of volume from liquid to gas helps enlarge the fissure and recover an additional amount of oil.

It’s not common knowledge that liquid CO2 is also used in the dry cleaning industry. In a certain high pressure washer, liquid CO2 is introduced with a stain remover. The clothes are then washed regularly employing turbulence to clean the wash. When the cycle is done, the dirt, grime and stain remover are separated from the liquid CO2. The liquid CO2 is then extracted to be recycled and the laundry is removed clean and dry since no water was used.

Every chemical (element or compound) has a state in which the three phases (gas, liquid and solid) have the same qualities and is reached through modification of temperature and pressure; this is called the supercritical state. The supercritical state of CO2 can be produced in a specially designed processor. When in its fluid phase, CO2 is a great solvent and is utilized in the extracting of fragrances and color from flowers and plants. The process is, of course, performed under high pressure and requires highly specialized equipment.

Solid

Solid CO2 or dry ice is applied in a wide variety of methods as a coolant. When liquid CO2 is sent through a high pressure line and released using special nozzles, it immediately becomes CO2 snow and is used in the refrigeration or freezing of food. Dry ice pellets replace regular ice in bins that hold perishables for long over-the-road transport.

Dry ice in very small form is (about the size of a grain of rice) utilized as an abrasive to remove coatings from surfaces without damaging the surface itself by launching the rice size pellets through a blasting lance. This is prominent in the aircraft industry in which the body of an airplane must remain intact and not suffer from the harm that sand blasting would cause. This is also advantageous because is that the removed coating does not have to be separated from the abrasive as the pellets sublimate to CO2 gas resulting in a simple cleanup.

Labeling CO2 as a super-gas may be controversial, but it is without a doubt the most versatile product available in the industrial gas market.

To find out more about how you can be supplied with carbon dioxide in El Paso for any of your specialty gas operations, call SYOXSA, Inc. at 915-771-7674 or at Esteban.Trejo@syoxsa.com.

John Segura, PE

About the Author

John Segura is a licensed Professional Engineer and an experienced executive in the industrial gas industry. He has over 30 years of experience covering sales, marketing and operations both domestic and international. Segura has well-rounded experience leading teams of engineers and technicians from his years as an R&D manager for large gas companies. His work caused his eventual leadership of the marketing efforts of technology worldwide industrial gas suppliers. He now consults to the industry on the business specializing in operations, applications and marketing.