Gases for Life
COVER STORY
Improving the carbon footprint with gases
By Diana Buss, Messer Group
Like many other companies, Messer publishes details of climate-damaging emissions caused by activities such as production and transport in its annual Corporate Responsibility Report. They are measured as CO₂ equivalent, also known as global warming potential.
The climate-damaging properties of emitted CO₂ are used as a measure for all other greenhouse gases, be it in connection with emissions from electricity and diesel consumption or the release of methane, for example, which has a far more polluting effect on the atmosphere than carbon dioxide. However, the use of gases such as oxygen, nitrogen and carbon dioxide itself can help to protect the environment and reduce the CO₂ equivalent. Gases and their applications can make products and processes more environmentally friendly. They help reduce the emission of greenhouse gases, increase production efficiency, avoid waste or quite directly save energy.
Reduction of 1,074,300 tons of CO₂ equivalent
Manufacturing and processing companies must ensure that they act in a sustainable way and protect our environment for society and future generations. Gas application technologies, combined with expert knowledge gained over many years, can reduce greenhouse gas emissions, which benefits the climate. In the area of industrial processes, the condensation of solvents is an important technology for reducing CO₂ equivalent emissions. In 2019, Messer’s chemical and pharmaceutical customers in Europe and Asia reduced CO₂e emissions by 34,300 tons – similar to the years before – by using our waste air cleaning processes. 30,000 tons of this reduction was achieved with a special process developed for a German customer in 1995 which facilitates the recovery of gaseous methyl chloride from the waste gas produced by reaction vessels. In this process, the methyl chloride is liquefied by cooling it with cryogenic nitrogen and subsequently reused in production. Units of this type are in use in Germany, Spain and China. A further two methyl chloride recovery units are currently being built and due to go into operation in Germany in 2020. The process is constantly being refined: for example, in addition to the cryogenic condensation stages, the latest design also features three downstream absorbers, which are regenerated with gaseous nitrogen. This extends the process’s scope of application and allows it to be used in methyl chloride logistics as well. Methyl chloride is the most abundant chlorine-containing compound in the atmosphere, with a global warming potential (GWP) of 13, which means that it is 13 times more climate-damaging than carbon dioxide. Other solvents are recovered with the Messer DuoCondex process. This also involves using the low temperature of liquid nitrogen to condense or freeze out these harmful substances from waste gas. A DuoCondex pilot facility was used to carry out extensive tests at a customer’s site, which culminated in the customer taking the unit and Messer being awarded a gas supply contract. The biggest contribution in terms of CO₂e reduction comes from the recovery of CFCs (chlorofluorocarbons) from the waste air of refrigerator recycling plants using the DuoCondex process. The extremely high GWP of these substances – they are 3,500 to 12,500 times more damaging than CO₂ – means that the annual environmental impact avoided in this area is approximately 1,040,000 tons of CO₂e.
Gas technologies benefit environment Messer supplies nitrogen and the cryogenic equipment for the recycling of wellington boot production waste using the cold grinding process. Messer has been working with a Central European customer in this field since 2012 and jointly carried out successful pilot tests for rubber waste recycling at the Krefeld Competence Center. The necessary cold grinding equipment for the recycling plant was installed in 2019. The cooling effect of the liquid gases (LIN, LOX, LCO₂) supplied to many customers simply goes to waste in their application. If, in parallel to the gas application, there is also a cooling requirement, then the Messer EcoVap vaporizer can be used to incorporate the cooling effect of the gas into the cooling circuit and thus save on electricity for the cooling process. Some 11 million kilos of industrial gases are now vaporized in EcoVap units every year, and this figure is increasing rapidly. This equates to an environmental benefit of approximately 1,500 metric tons of CO₂e. In metallurgy, oxyfuel combustion makes a significant contribution to reducing fuel consumption in high-temperature processes. This is particularly the case where non-preheated air had previously been used as the oxidant. In 2019, Messer converted several furnaces in the non-ferrous sector and others in the glass industry to oxyfuel combustion for customers in Europe, Vietnam and China.
Reducing energy consumption in the air separation process Messer aims to reduce the specific energy consumption of its air separation units by an average of 0.7 per cent annually in the long term. This is to be achieved through better capacity utilization of production facilities, continuous investment in even more efficient processes and targeted projects aimed at improving energy efficiency. Since 2014, Messer has had a dedicated Global Energy Officer (GEO) with responsibility for energy management. Messer Group’s specific energy consumption – including its Western European entities – fell by 1.6 per cent in 2019 compared with 2018. The corresponding data for Messer in North and South America will be available for the first time for the 2020 financial year. Air separation units process ambient air without producing any toxic or environmentally harmful emissions. Even in the event of a shutdown or malfunction, only natural air components are emitted. Our products are gases that are supplied either in gaseous form by pipeline, in cryogenically liquefied form in tankers (to fill customer tanks) or in compressed gaseous form in steel cylinders. Only cylinder gases are packaged products. Steel gas cylinders are generally rented out to customers and returned empty after use. They are therefore 100% reusable – following the necessary cleaning and checks – and typically have a service life of at least 20 years.