In Mississippi, when people think of natural resources, oil and gas come to mind. Few people are aware of another plentiful natural resource.
“The state is blessed with carbon dioxide,” according to Kerry Allen, Mississippi operations and production manager of Denbury Resources Inc.
Denbury is Mississippi`s largest independent oil and gas producer and its only producer of carbon dioxide. In a process called “through the bit,” carbon dioxide is used to enhance oil wells that were abandoned because they were no longer productive. Denbury also produces carbon dioxide as a product itself.
Carbon dioxide production is similar to natural gas production, with the same drilling and completion processes, according to Mark Worthey, Denbury senior vice president.
“But with carbon dioxide, chrome tubing is used instead of steel tubing, because carbon dioxide mixed with water forms an acid that damages steel,” Worthey said.
All of the state`s carbon dioxide comes from three fields – Goshen Springs, Picah and Holly Bush Creek – in northern Rankin County not far from Jackson.
“We have about 15 wells in Rankin County,” Worthey said. “The carbon dioxide exists in those fields because there`s an ancient volcano under Jackson and when it erupted, the gasses went into underground formations.”
Carbon dioxide production is measured the same way natural gas is measured, by cubic feet, and indicated by “MCF” for thousands of cubic feet and “MMCF” for millions. In the three Rankin County fields, some 235 MMCF are produced daily. Of this total, 70 MMCF a day are used for commercial products and 165 MMCF for enhancing oil wells.
Denbury runs the carbon dioxide through a plant that strips it of water, then it`s piped to oil fields in Lincoln and Pike Counties in southwestern Mississippi.
For the enhancing process, Worthey said to imagine a square with an oil well at each corner and one in the center. Carbon dioxide is pumped into the central well and it runs to the other wells and forces oil out of rocks, in a way that no other process can duplicate.
“It works like a detergent and mixes with the oil,” Worthey said. “It`s like using soda to get wine off of clothing. Dry cleaning is similar, because carbon dioxide is used.”
In Mississippi, some 8,200 barrels of oil a day come from enhancing wells with carbon dioxide. This is 18% of all the oil produced in the state. Worthey added that in Texas, where Denbury has its headquarters, 10% of the oil produced is enhanced by carbon dioxide.
Denbury is now studying the feasibility of building a carbon dioxide pipeline into East Mississippi.
Carbon dioxide is an odorless, colorless gas. All green plants must have carbon dioxide to live and grow. Carbon dioxide is produced when animals change food into energy and living matter. The burning of any substance that contains carbon – wood, coal, gasoline – also produces carbon dioxide.
Though most people are not aware of carbon dioxide as a natural resource pumped from the ground like oil and gas, they use products made possible by it every day. Carbon dioxide causes the fizz in soda, beer and sparkling wine. When added to flour, baking powder reacts with air and water or milk to form carbon dioxide gas. The resulting bubbles are trapped in the flour and, when heated, they expand and cause the mixture to rise.
Some gas fire extinguishers have liquefied carbon dioxide under pressure in the container, because it doesn`t burn and its heaviness allows it to blanket a flame and keep oxygen in the air from reaching the fire.
Dry ice, widely used by industries to refrigerate medicines, food and other materials that might be damaged by the melting of ice made from water, is solid carbon dioxide. It`s called dry ice because, at normal temperatures, it sublimes – changes from a solid to a gas without first becoming liquid.
Most anything a person might order by phone or online that has to be shipped frozen – meat, dessert, other food items – are packed with dry ice. Dry ice, mixed with isopropyl alcohol or acetone, is used by chemists to cool chemicals during certain reactions. Carbon dioxide is also used in anti-acid products.
Denbury came into existence in Mississippi in 1990, buying and developing oil properties left behind, mostly by major oil companies. In the past couple of years, Allen said, Denbury has shifted its focus to enhancing the southwestern Mississippi oil properties that it owns with the “through the bit” process of using carbon dioxide.
“This brings new life to old oil fields,” Allen said. “If these fields weren`t enhanced, they’d have to be plugged and left behind.”
Worthey indicated that the “flooding” of oil fields with carbon dioxide – as it`s called in the industry – has been going on in Mississippi since 1985. The process was started in the state by Chevron and Shell and later sold to Air Gas. Denbury then bought the Air Gas assets.
Contact MBJ contributing writer at George McNeill at email@example.com.