the essence of frigidity

The front of the American grocery store contains a strange, liminal space: the transitional area between parking lot and checkstand, along the front exterior and interior of the building, that fills with oddball commodities. Ice is a fixture at nearly every store, filtered water at most, firewood at some. This retail purgatory, both too early and too late in the shopping journey for impulse purchases, is mostly good only for items people know they will need as they check out. One of the standard residents of this space has always struck me as peculiar: dry ice.

Carbon dioxide ice is said to have been invented, or we might better say discovered, in the 1830s. For whatever reason, it took just about a hundred years for the substance to be commercialized. Thomas B. Slate was a son of Oregon, somehow ended up in Boston, and then realized that the solid form of CO2 was both fairly easy to produce and useful as a form of refrigeration. With an eye towards marketing, he coined the name Dry Ice—and founded the DryIce Corporation of America. The year was 1925, and word quickly spread. In a widely syndicated 1930 article, "Use of Carbon Dioxide as Ice Said to be Developing Rapidly," the Alamogordo Daily News and others reported that "the development of... 'concentrated essence of frigidity' for use as a refrigerant in transportation of perishable products, is already taxing the manufacturing facilities of the Nation... So rapidly has the use of this new form of refrigeration come into acceptance that there is not sufficient carbon dioxide gas available."

The rush to dry ice seems strange today, but we must consider the refrigeration technology of the time. Refrigerated transportation first emerged in the US during the middle of the 19th century. Train boxcars, packed thoroughly with ice, carried meat and fruit from midwestern agriculture to major cities. This type of refrigerated transportation greatly expanded the availability of perishables, and the ability to ship fruits and vegetables between growing regions made it possible, for the first time, to get some fresh fruit out of season. Still, it was an expensive proposition: railroads built extensive infrastructure to support the movement of trains loaded down with hundreds of tons of ice. The itself had to be quarried from frozen lakes, some of them purpose-built, a whole secondary seasonal transportation economy.

Mechanical refrigeration, using some kind of phase change process as we are familiar with today, came about a few decades later and found regular use on steamships by 1900. Still, this refrigeration equipment was big and awkward; steam power was a practical requirement. As the Second World War broke out, tens of thousands of refrigerated railcars and nearly 20,000 refrigerated trucks were in service—the vast majority still cooled by ice, not mechanical refrigeration.

You can see, then, the advantages of a "dryer" and lighter form of ice. The sheer weight of the ice significantly reduced the capacity of refrigerated transports. "One pound of carbon dioxide ice at 110 degrees below zero is declared to be equivalent to 16 pounds of water ice," the papers explained, for the purposes of transportation. The use of dry ice could reduce long-haul shipping costs for fruit and vegetables by 50%, the Department of Commerce estimated, and dry ice even opened the door to shipping fresh produce from the West Coast to the East—without having to "re-ice" the train multiple times along the way. Indeed, improvements in refrigeration would remake the American agricultural landscape. Central California was being irrigated so that produce could grow, and refrigeration would bring that produce to market.

1916 saw the American Production Company drilling on the dusty plains of northeastern New Mexico, a few miles south of the town of Bueyeros. On the banks of an anonymous wash, in the shadow of Mesa Quitaras, they hoped to strike oil. Instead, at about 2,000 feet, they struck something else: carbon dioxide. The well blew wide open, and spewed CO2 into the air for about a year, the production estimated at 25,000,000 cubic feet of gas per day under natural pressure. For American Production, this was an unhappy accident. They could identify no market for CO2, and a year later, they brought the well under control, only to plug and abandon it permanently.

Though the "No. 1 Bueyeros" well was a commercial failure at the time, it was not wasted effort. American Production had set the future for northeastern New Mexico. There was oil, if you looked in the right place. American Production found its own productive wells, and soon had neighbors. Whiting Brothers, once operator of charismatic service stations throughout the Southwest and famously along Route 66, had drilled their own wells by 1928. American Production became part of British Petroleum. Breitburn Production of Texas has now consolidated much of the rest of the field, and more than two million cubic feet of natural gas come from northeastern New Mexico each month.

If you looked elsewhere, there was gas—not natural gas, but CO2. Most wells in the region produced CO2 as a byproduct, and the less fortunate attempts yielded nothing but CO2. The clear, non-flammable gas was mostly a nuisance in the 1910s and 1920s. By the 1930s, though, promotion by the DryIce Corporation of America (in no small part through the Bureau of Commerce) had worked. CO2 started to be seen as a valuable commodity.

The production of dry ice is deceptively simple. Given my general knowledge about producing and handling cryogenic gases, I was surprised to read of commercial-scale production with small plants in the 1930s. There is, it turns out, not that much to it. One of the chief advantages of CO2 as an industrial gas is its low critical temperature and pressure. If you take yourself back to high school chemistry, and picture a phase diagram, we can think about liquifying the CO2 gas coming out of a well. The triple point of carbon dioxide, where increasing pressure and temperature will make it a liquid, is at around -60 Celsius and 5 atmospheres. The critical point, beyond which CO2 becomes a supercritical gas-fluid hybrid, is only at 30 degrees Celsius and 72 atmospheres. In terms more familiar to us Americans, that's about 88 degrees F and 1,000 PSI.

In other words, CO2 gas becomes a liquid at temperatures and pressures that were readily achievable, even with the early stages of chemical engineering in the 1930s. With steam-powered chillers and compressors, it wasn't difficult to produce liquid CO2 in bulk. But CO2 makes the next step even more convenient: liquid CO2, released into open air, boils very rapidly. As it bubbles away, the phase change absorbs energy, leaving the remaining liquid CO2 even colder. Some of it freezes into ice, almost like evaporating seawater to extract the salt, evaporating liquid CO2 leaves a snow-like mass of flaky, loose CO2 ice. Scoop that snow up, pack it into forms, and use steam power or weight to compress it, and you have a block of the product we call dry ice.

The Bueyeros Field, as it was initially known, caught the interest of CO2 entrepreneurs in 1931. A company called Timmons Carbonic, or perhaps Southern Dry Ice Company (I suspect these to be two names for the same outfit), produced a well about a mile east, up on the mesa.

Over the next few years, the Estancia Valley Carbon Dioxide Development Company drilled a series of wells to be operated by Witt Ice and Gas. These were located in the Estancia field, further southwest and closer to Albuquerque. Witt built New Mexico's first production dry ice plant, which operated from 1932 to 1942 off of a pipeline from several nearby wells. Low pressure and difficult drilling conditions in the Estancia field limited the plant's output, so by the time it shut down Witt had already built a replacement. This facility, known as the Bueyeros plant, produced 17 tons of dry ice per day starting in 1940. It is located just a couple of miles from the original American Production well, north of Mesa Quitaras.

About 2,000' below the surface at Bueyeros lies the Tubb Sandstone, a loose aggregation of rock stuck below the impermeable Cimarron Anhydrite. Carbon dioxide can form underground through several processes, including the breakdown of organic materials under great heat and pressure (a process that creates petroleum oil as well) and chemical reactions between different minerals, especially when volcanic activity causes rapid mixing with plenty of heat. There are enough mechanisms of formation, either known or postulated, that it's hard to say where exactly the CO2 came from. Whatever its source, the gas flowed upwards underground into the sandstone, where it became trapped under the airtight layer of Anhydrite. It's still there today, at least most of it, and what stands out in particular about northeastern New Mexico's CO2 is its purity. Most wells in the Bueyeros field produce 99% pure CO2, suitable for immediate use.

Near Solano, perhaps 20 miles southwest of Bueyeros by air, the Carbonic Chemical Co built the state's largest dry ice plant. Starting operation in 1942, the plant seems to have initially gone by the name "Dioxice," immortalized as a stop on the nearby Union Pacific branch. Dioxice is an occasional synonym for Dry Ice, perhaps intended to avoid the DryIce Corporation's trademark, although few bothered. The Carbonic Chemical Plant relied on an 18 mile pipeline to bring gas from the Bueyeros field. Uniquely, this new plant used a "high pressure process." By feeding the plant only with wells producing high pressure (hundreds of PSI, as much as 500 PSI of natural pressure at some wells), the pipeline was made more efficient and reliable. Further, the already high pressure of the gas appreciably raised the temperature at which it would liquefy.

The Carbonic Chemical plant's ammonia chillers only had to cool the CO2 to -15 degrees F, liquifying it before spraying it into "snow chambers" that filled with white carbon dioxide ice. A hydraulic press, built directly into the snow chamber, applied a couple of hundred tons of force to create a solid block of dry ice weighing some 180 pounds. After a few saw cuts, the blocks were wrapped in paper and loaded onto insulated train cars for delivery to customers throughout the west—and even some in Chicago.

The main applications of CO2, a 1959 New Mexico Bureau of Mines report explains, were dry ice for shipping. Secondarily, liquid CO2 was shipped in tanks for use in carbonating beverages. Witt Ice and Gas in particular built a good business out of distributing liquid CO2 for beverage and industrial use, and for a time was a joint venture with Chicago-based nationwide gas distributor Cardox. Bueyeros's gas producers found different customers over time, so it is hard to summarize their impact, but we know some salient examples. Most beverage carbonation in mid-century Denver, and perhaps all in Albuquerque, used Bueyeros gas. Dry ice from Bueyeros was used to pack train cars passing through from California, and accompanied them all the way to the major cities of the East Coast.

By the 1950s, much of the product went to a more modern pursuit. Experimental work pursued by the military and the precursors to the Department of Energy often required precise control of low temperatures, and both solid and liquid CO2 were suitable for the purpose. In the late 1950s, Carbonic Chemical listed Los Alamos Scientific Laboratory, Sandia Laboratories, and White Sands Missile Range as their primary customers.

Bueyeros lies in Harding County, New Mexico. Harding County is home to two incorporated cities (Roy and Mosquero), a couple of railroad stops, a few highways, and hardly 650 people. It is the least populous county of New Mexico, but it's almost the size of Delaware. Harding County has never exactly been a metropolis, but it did used to be a more vital place. In the 1930s, as the CO2 industry built out, there were almost 4,500 residents. Since then, the population has declined about 20% from each census to the next.

CO2 production went into a similar decline. After the war, significant improvements in refrigeration technology made mechanical refrigeration inevitable, even for road transportation. Besides, the growing chemical industry had designed many industrial processes that produced CO2 as a byproduct. CO2 for purposes like carbonation and gas blanketing was often available locally at lower prices than shipped-in well CO2, leading to a general decline in the CO2 industry.

Growing understanding of New Mexico geology and a broader reorganizing of the stratigraphic nomenclature lead the Bueyeros Field to become part of the Bravo Dome. Bravo Dome CO2 production in the 1950s and 1960s was likely supported mostly by military and weapons activity, as by the end of the 1960s the situation once again looked much like it did in the 1910s: the Bravo Dome had a tremendous amount of gas to offer, but there were few applications. The rate of extraction was limited by the size of the market. Most of the dry ice plants closed, contributing, no doubt, to the depopulation of Harding County.

The whole idea of drilling for CO2 is now rather amusing. Our modern problems are so much different: we have too much CO2, and we're producing even more without even intending to. It has at times seemed like the industry of the future will be putting CO2 down into the ground, not taking it out. What happened out in Harding County was almost the opening of Pandora's box. A hundred years ago, before there was a dry ice industry in the US, newspaper articles already speculated as to the possibility of global warming by CO2. At the time, it was often presented as a positive outcome: all the CO2 released by burning coal would warm the environment and thus reduce the need for that coal, possibly even a self-balancing problem. It's even more ironic that CO2 was extracted mostly to make things colder, given the longer-term consequences. Given all that, you would be forgiven for assuming that drilling for CO2 was a thing of the past.

The CO2 extraction industry has always been linked to the oil industry, and oil has always been boom and bust. In 1982, there were 16 CO2 wells operating in the Bravo Dome field. At the end of 1985, just three years later, there were 258. Despite the almost total collapse of demand for CO2 refrigeration, demand for liquid CO2 was up by far. It turns out that American Production hadn't screwed up in 1917, at least not if they had known a little more about petroleum engineering.

In 1972, the Scurry Area Canyon Reef Operators Committee of West Texas started an experiment, attempting industrial application of a technique first proposed in the 1950s. Through a network of non-productive oil wells in the Permian Basin, they injected liquid CO2 deep underground. The rapidly evaporating liquid raised the pressure in the overall oil formation, and even lubricated and somewhat fractured the rock, all of which increased the flow rate at nearby oil wells. A decade later, the concept was proven, and CO2 Enhanced Oil Recovery (EOR) swept across the Permian Basin.

Today, it is estimated that about 62% of the global industrial production of CO2 is injected into the ground somewhere in North America to stimulate oil production. The original SACROC system is still running, now up to 414 injection wells. There are thousands more. Every day, over two billion cubic feet of CO2 are forced into the ground, pushing back up 245,000 barrels of additional oil.

British Petroleum's acquisition of American Production proved fortuitous. BP became one of the country's largest producers of CO2, extracted from the ground around Bueyeros and transported by pipeline directly to the Permian Basin for injection. In 2000, BP sold their Bravo Dome operations to Occidental Petroleum ¹. Now going by Oxy, the petroleum giant has adopted a slogan of "Zero In". That's zero as in carbon emissions.

I would not have expected to describe Occidental Petroleum as "woke," but in our contemporary politics they stand out. Oxy mentions "Diversity, Inclusion, and Belonging" on the front page of their website, which was once attractive to investors but now seems more attractive to our nation's increasingly vindictive federal government. Still, Oxy is sticking to a corporate strategy that involves acknowledging climate change as real, which I suppose counts as refreshing. From a 2025 annual report:

Oxy is building an integrated portfolio of low-carbon projects, products, technologies and companies that complement our existing businesses; leveraging our competitive advantages in CO2 EOR, reservoir management, drilling, essential chemicals and major infrastructure projects; and are designed to sustain long term shareholder value as we work to implement our Net-Zero Strategy.

Yes, Oxy has made achieving net-zero carbon a major part of their brand, and yes, this model of reducing carbon emissions relies heavily on CO2 EOR: the extraction of CO2 from the ground.

In a faltering effort to address carbon emissions, the United States has leaned heavily on the promise of Carbon Capture and Storage (CCS) technologies. The idea is to take CO2 out of the environment (potentially by separating it from the air but, more practically, by capturing it in places where it is already concentrated by industrial processes) and to put it somewhere else. Yes, this has shades of the Australian television sketch about the ship whose front fell off, but the key to "sequestration" is time. If we can put enough carbon somewhere that it will say for enough time, we can reduce the "active" greenhouse gas content of our environment. The main way we have found of doing this is injecting it deep underground. How convenient, then, that the oil industry is already looking for CO2 for EOR.

CCS has struggled in many ways, chief among them that the majority of planned CCS projects have never been built. As with most of our modern carbon reduction economy, even the CCS that has been built is, well, a little bit questionable. There is something of a Faustian bargain with fossil fuels. As we speak, about 45 megatons of CO2 are captured from industrial processes each year for CCS. Of that 45 Mt, 9 Mt are injected into dedicated CO2 sequestration projects. The rest, 80%, is purchased by the oil industry for use in EOR.

This form of CCS, in which the captured CO2 is applied to an industrial process that leads to the production of more CO2, has taken to the name CCUS. That's Carbon Capture, Utilization, and Storage. Since the majority of the CO2 injected for EOR never comes back up, it is a form of sequestration. Although the additional oil produced will generally be burned, producing CO2, the process can be said to be inefficient in terms of CO2. In other words, the CO2 produced by burning oil from EOR is less in volume than the CO2 injected to stimulate recovery of that oil.

Mathematically, CCUS, the use of CO2 to produce oil, leads to a net reduction in released CO2. Philosophically, though, it is deeply unsatisfying. This is made all the worse by the fact that CCUS has benefited from significant government support. Outright subsidies for CCS are uncommon, although they do exist. What are quite common are grants and subsidized financing for the capital costs of CCS facilities. Nearly all CCS in the US has been built with some degree of government funding, totaling at least four billion dollars, and regulatory requirements for CCS to offset new fossil fuel plants may create a de facto electrical ratepayer subsidy for CCS. Most of that financial support, intended for our low-carbon future, goes to the oil producers.

The Permian Basin is well-positioned for CCS EOR because it produces mostly natural gas. Natural gas in its raw form, "well gas," almost always includes CO2. Natural gas processing plants separate the combustible gases from noncombustible ones, producing natural gas that has a higher energy content and burns more cleanly—but, in the process, venting large quantities of CO2 into the atmosphere. Oxy is equipping its Permian Basin natural gas plants with a capture system that collects the CO2 and compresses it for use in EOR.

The problem is that CO2 consumption for EOR has, as always, outpaced production. There aren't enough carbon capture systems to supply the Permian Basin fields, so "sequestered" CO2 is mixed with "new" CO2. Bravo Dome CO2 production has slowly declined since the 1990s, due mostly to declining oil prices. Even so, northeastern New Mexico is still full of Oxy wells bringing up CO2 by the millions of cubic feet. 218 miles of pipeline deliver Bueyeros CO2 into West Texas, and 120 miles of pipeline the other way land it in the oil fields of Wyoming. There is very nearly one producing CO2 well per person in Harding County.

Considering the totality of the system, it appears that government grants, financing incentives, and tax credits for CCS are subsidizing not only natural gas production but the extraction of CO2 itself. Whether this is progress on climate change or a complete farce depends a mathematical analysis. CO2 goes in, from several different sources; CO2 goes out, to several different dispositions. Do we remove more from the atmosphere than we end up putting back? There isn't an obvious answer.

The oil industry maintains that CCS is one of the most practical means of reducing carbon emissions, with more CO2 injected than produced and a resulting reduction in the "net CO2 impact" of the product natural gas.

As for more independent researchers, well, a paper finding that CCS EOR "cannot contribute to reductions" isn't the worst news. A 2020 literature review of reports on CCS EOR projects found that they routinely fail to account for significant secondary carbon emissions and that, due to a mix of the construction and operational realities of CCS EOR facilities and the economics of oil consumption, CCS EOR has so far produced a modest net increase in greenhouse gas emissions.

They're still out there today, drilling for carbon dioxide. The reports from the petroleum institute today say that the Permian Basin might need even more shipped in. New Mexico is an oil state; Texas gets the reputation but New Mexico has the numbers. Per-capita oil production here is significantly higher than Texas and second only to North Dakota. New Mexico now produces more oil than Old Mexico, if you will, the country to our south.

Per capita, New Mexico ranks 12th for CO2 emissions, responsible for about 1% of the nation's total. Well, I can do a bit better: for CO2 intentionally extracted from the ground, New Mexico is #3, behind only Colorado and Mississippi for total production. We produce something around 17% of the nation's supply of extracted CO2, and we even use most of it locally. I guess that's something you could put a good spin on.