Through years of experience ACP has become the specialist in the field of carbon dioxide and strives to expand its expertise even further in daily practice. In order to convey this message to industrial bulk customers, ACP decided to use an equal sign in its company logo acp=co2, which is printed on all ACP documents. Next to that ACP also uses the word “acpco2” in all registered domain names.

Carbon dioxide is a molecule consisting of one carbon atom and two oxygen atoms, and is generally referred to as 'CO2', which is its chemical formula.

Carbon dioxide was discovered in the early 17th century by the Flemish scientist Jan Baptista van Helmont. He was the first scientist to acknowledge there are different sorts of gases. He invented the word "gas" (which stems from the Greek word chaos) and observed that the "spiritus sylvestre" (or the wild spirit) was released during the combustion of charcoal.

In early 1770 Torbern Bergman discovered that an equal volume of CO2 gas was almost entirely soluble in water at a temperature of 10°C and observed that the solubility of this gas decreases as the temperature rises. By means of taste experiments and litmus paper he found out that the solution was slightly acidulous, which inspired him to use it in the production of artificial mineral waters.

In 1834 Faraday managed to liquefy carbon dioxide, be it only on a lab level. It would only be in Germany in 1884, however, that liquid CO2 was produced on an industrial scale, because of an increasing demand from mineral water producers and breweries.

In 1897 ACP was founded. At first ACP produced CO2 by recovering CO2 gases in limekilns. Later on CO2 was recovered from combustion of cokes and still later on from combustion of heavy fuel oil. Today ACP recovers CO2 gases from ammonia producers.

In 1854 Faraday also succeeded in producing dry ice on a lab level. It would only be in 1925, however, that dry ice was produced commercially for the first time from out of the United States.

Carbon dioxide occurs in three forms: as a solid (also called dry ice), a liquid and a gas.
Gaseous CO2 is found in low concentrations in the atmosphere as a greenhouse gas. Atmospheric carbon dioxide is produced from volcanic activity, the combustion of organic materials and the respiration process of all aerobic organisms.

Besides that carbon dioxide is also produced by the combustion of fossil fuels (e.g. in transportation), and by several micro-organisms (e.g. during photosynthesis). Atmospheric carbon dioxide concentrations can vary from 0.03% to 0.06%, depending on the location. Inhalation of low concentrations of CO2 (as of 5%) can cause dizziness, while inhalation of high concentrations of CO2 (as of 10%) can cause asphyxiation, resulting ultimately in death.

Because of its unique properties carbon dioxide is used in several industrial applications. That is why in 2005 ACP decided to found the Technology Center, which focuses on all sorts of industrial CO2 applications for bulk customers. The Technology Center keeps a close track of the latest trends and developments, in order to make sure that the industrial customers, in cooperation with ACP, can decide on the CO2 storage tanks that meet their requirements most.

Carbon dioxide is an odorless, colorless gas and has a limited solubility in water. When CO2 gas is solved in water it forms a weak acid: acid carbonate also known as carbonic acid. This mineral acid and the base components in the water react with each other. On top of that carbon dioxide is a non-toxic and non-corrosive gas, making it a recommendable solution to treat (waste)waters, in stark contrast with strong acids such as sulfuric acid and chloric acid. Using CO2 to neutralize the pH level in water is therefore an ecologically sound process, as a CO2 injection does not bring about excessive acidification of the water nor does it introduce any pollutants to it.

In the beverage industry carbon dioxide is frequently used in several applications, for instance in the carbonization of beverages. CO2 adds a refreshing taste and also prevents fungi and bacteria growth. In 2000 ACP developed the Safe-for-Food program to meet the sector’s very specific and high standards. This program provides a number of additional inspections and services in order to guarantee impeccable food quality.

Breweries, including their customers like public houses, restaurants, etc., are also large CO2 consumers and use carbon dioxide as propellant gas. As these consumers use smaller quantities of carbon dioxide, CO2 is delivered in gas cylinders and minibulk storage tanks. As the leading producer of carbon dioxide, Eurocylinder is the main supplier of CO2 in cylinders and minibulk. Due to the constantly rising safety and hygiene standards, Eurocylinder now disposes of an extensive fleet of aluminum cylinders, which are equipped with an advanced locking system (residual pressure valve).

Moreover, Eurocylinder offers a solution to large 'gas cylinder consumers', namely the minitank or minibulk. The minitank is a small CO2 reservoir and is the perfect solution for catering industry customers who consume approximately 500 kg of CO2 a year. The minibulk system is fully automated and does not require electric power, maintenance or other adjustments by the user. It is a low-pressure reservoir that serves as a perfect substitute for high-pressure cylinders. CO2 is fed through the external filling cabinet.

In the food industry carbon dioxide is used because of its low temperature and bacteriostatic properties. It can be used in different forms: as a solid (also called dry ice), a liquid or a gas and to different ends like for instance cooling and freezing foods.
ACP has therefore developed a snow generator with unique features that is very suitable for fragile food products: the SnowCool.

The density of CO2 at standard temperature and pressure is approximately 1.98 kg/m3, making it 1.53 times denser than air. As a result CO2 gas sinks to ground level and can easily be dispersed by good ventilation.

Given that carbon dioxide is completely oxidized, it is non-aggressive and fairly non-flammable. That is why CO2 is also used for inerting atmospheres or as an extinguishing agent.

Some typical properties::

• CO2 cannot exist as a liquid at normal atmospheric pressure
• CO2 can not be liquefied at temperatures above 31 °C.
• Dry ice sublimates into CO2 gas at atmospheric pressure
• CO2 becomes “supercritical” at temperatures above 31 °C

ACP disposes of 3 CO2 production units: Carbolim, Carbowil and Carbodour. Carbolim was set up in 1985 and is located in Geleen, the Netherlands. In 1993 ACP decided to upgrade Carbolim’s production capacity to 30 t CO2/hour. Then in 1998 ACP decided to invest in a new production unit in Tertre, Belgium, thereby creating Carbodour, with a production capacity of 15 t CO2/hour.
Given its steady growth on the European market, ACP took the opportunity to set up a production unit in Włocławek, Poland, in 2001. And because of the increasing success in Poland, a new production unit is now being built in Carbowil, which currently has a production capacity of 22.5 t CO2/hour.

ACP also disposes of two dry ice production units, namely in Heusden-Zolder and Włocławek.

Dry ice or CO2 in its solid form is obtained by expanding liquid CO2 at atmospheric pressure. During this expansion process, 50% of the liquid CO2 turns into gas - which will be recovered - while the other 50% turns into CO2 snow. This CO2 is compressed in high-pressure extruders or hydraulic presses, turning it in into pellets (small sticks) or blocks.

In late 2004 Cold Jet Benelux and Cold Jet Polska were founded. These two companies focus on dry ice blasting, a cleaning technique using dry ice pellets. Servicing of machinery by the way is indeed an important factor in industrial activities. Besides high-quality dry ice Cold Jet Benelux and Cold Jet Polska offer - under the brand name Coldjet - a wide range of very reliable dry ice blasters, nozzles and accessories for all types of cleaning methods and surface treatments, designed to match every budget. The cleaning principle of dry ice blasting is based on the use of dry ice: compressed air fed by the dry ice blasting machine accelerates the dry ice pellets to a high velocity, after which they are blasted at the surface to be treated by means of a spray-gun. Cold Jet, in other words, offers its customers an ecologically sound cleaning technique and enables them to cut cleaning costs considerably.

Cold Jet Benelux and Cold Jet Polska offer a wide range of dry ice blasting machines, such as the Aero 30, the Aero 75, the Aero 75-DX and the i3 Microclean, which are electrically powered, and the Power PT, the Power PTX and the SDI-5, which are pneumatically powered. The i3 Microclean is equipped with a very small spray-gun and nozzles the size of a pencil, making it a precision cleaning solution. The SDI-5 and the Power PTX are the only blasters equipped with a dual-hose system.

Dry ice blasting is used in a wide range of applications, making the servicing of machinery considerably less laborious. Some examples of applications are: cleaning injection moulds, industrial waffle irons, electrical parts, and so on.

In 2006 ACP decided to cooperate with a Dutch company called ICS, whose core activity is the transport of cooled and deep-frozen shipments. Through this cooperation with ICS, ACP aims at expanding its expertise in the field of dry ice transport.

Keywords: co2, dry ice, carbon dioxide, carbonic acid.