Bad Soden, Germany,

Carbon dioxide – a gas that can also relieve the environment

CO2 aids "dying" oilfields, provides pure water and can even be recycled.

Of all things, carbon dioxide (CO2) – one of the main causes of global climate change – seems to be a true revelation when it comes to the more efficient use of resources. The reason for this surprising development is the possibility to utilize oilfields more efficiently and to their full potential with carbon dioxide. The industrial gas company Messer already helped oil production back in 2004. A pilot project named EOR (Enhanced Oil Recovery) was conducted together withCroatian business partner INA Naftaplin. Carbon dioxide also helps to conserve the environment in other areas.

Nothing new: The natural resources of fossil fuels, such as oil and natural gas are limited. It could already come to shortages in this century if the demand keeps on rising at the present rate. However, several years ago, drilling experts discovered that the introduction of CO2 into a sealed oilfield helps to bring more oil to the surface. In 2004 the industrial gas specialist Messer successfully tested oil recovery in Croatia with carbon dioxide for the first time in Eastern Europe.

The goal was to check the effect of introducing CO2 in an existing oilfield. For the first two test cycles, two 16,000-ton shipments of liquid carbon dioxide were delivered to the drilling location of the client in Ivanic Grad. There it was stored in appropriate tanks and pumped into the earth at a pressure of about 100 bar. The results of the first two test cycles were completely convincing: INA Naftaplin decided against three further test phases and started the main project on a larger scale.

The extra amount of oil that can be extracted in this way is enormous, often ten to fifteen percent of the oil reserve (OOIP – "original oil in place") is possible. This can prolong economic oil production by several years – as seen in the case of Croatia. A study elaborated for Messer indicates a potential of 1300 million barrels of additional yield throughCO2-technology on the European continent alone. This is enough to completely supply Germany for over a year. Another benefit is that the injected CO2 stays in the oilfield and does not return to the environment. On average for each barrel of oil which is additionally produced, one third of a ton of carbon dioxide remains stored. A double benefit for the environment!

In addition to the economic success and the important contribution against global warming, the project had another positive effect: it underscored just how forward-looking and strong the Croatian economy is – which sends out a clear signal on Croatia's way to becoming an EU Member Country.

For Messer, the use of carbon dioxide for oil production is one of many environment-friendly applications for the gas known in Germany as the "climate killer". Part of the core competency of the world's largest family-managed industrial gas company is to develop new solutions or improve existing ones, and thereby relieve the strain on the environment. This involves reusing, i.e. recycling, the carbon dioxide which forms as a waste product in industrial processes. High-purity carbonic acid for the food and beverage industry, in contrast, originates from ground wells. In the food industry, the ultracold gas is generally used for cooling/freezing or as carbonic acid. In many cases, blasting with dry ice pellets has already displaced other blasting procedures in the manufacturing industry. Pellets made of dry ice are small, solid and cold. If pellet are shot under pressure onto a soiled surface, the dirt contracts and thereby detaches itself from the surface. Then it is simply blown away by the air pressure and the subsequent pellets. The result is pure dirt – it is not necessary to dispose of sand or wastewater. In purification plants and water treatment facilities, the addition of CO2 ensures a controlled pH, which means that chemical agents or aggressive mineral acids are no longer required in such large quantities. There are many sides to carbon dioxide!