The use of carbon dioxide in the beverage industry is essential: in beer, lager and cider production, this gas is used within the process to achieve consistently high quality products.
Carbon dioxide for breweries and cider maker is, therefore, a key element. How can procurement take place? In this situation, CO2 can be almost entirely self-produced by recycling it in the fermentation process.
TPI (Tecno Project Industriale), a SIAD Group company, was among the first companies globally to introduce a system to recover CO2 produced by beer fermentation using distillation technology (stripper + reboiler).
This system can collect, purify, and store carbon dioxide in liquid form in special tanks, limiting its release into the atmosphere and allowing it to be reused during other stages of production. Currently, the application of this technology is accepted for all industrial breweries.
Let’s take a look at what the CO2 recovery process is and how it happens in practice and the benefits it provides to breweries that equip themselves with such technology.
Brewing and carbon dioxide: the context
The beer fermentation process has a cycle of a few weeks, and it is during this period that carbon dioxide is developed.
In the first few days, the CO2 produced by fermentation contains sulfur components, alcohols and aldehydes which are impossible to reuse because it is of poor quality.
It takes time for it to improve naturally, and this involves releasing a large amount of carbon dioxide into the atmosphere, among other things, with suboptimal quality results anyway.
That is why in the brewing industry, for 30 years now, a practice typical of the petrochemical industry has been borrowed, strippage (or stripping): the distillation technology that allows the last residual oxygen to be removed more quickly from liquid CO2, bringing it down to below 5 parts per million.
Hence the CO2 recovery technology called “Early Recovery,” first installed by TPI in a historic brewery of the SAB Miller Group in Poland. In this first plant, through this technology, the carbon dioxide recovery could in fact occur early as early as the attainment, within the fermenter, of a quality of CO22 in the range of 95%, ensuring both recovery of more CO22 and at the same time, to achieve an oxygen content in the CO22 liquid such that there is no short-term spoilage of the final product. This first step was a revolution for the industry, as it enabled industrial breweries to recover enough CO2 to be self-sufficient in its supply.
Today we have gone further; CO2 recovery, purification, liquefaction and storage are a widespread standard, enabling not only reuse within the brewery itself but also, in some cases, use in the carbonation of other beverages.
This recycling activity is an excellent example of the direction taken by the SIAD Group for many years now: the enhancement of a process capable of reducing consumption and zeroing out waste, a transition that is now necessary to protect the planet as evidenced by the focus on the issue in the UN 2030 Agenda for Sustainable Development.
Beer and CO2 recovery, from fermentation to bottling with Early Recovery
But how does this process of CO2 recovery and reuse happen in breweries in practice? Here, in brief, is how TPI’s Early Recovery works.
Washing
As we anticipated, CO2 is formed by the alcoholic fermentation of the constituent components of beer and lager (water, yeast, hops and grains). From the fermenters, carbon dioxide is first conveyed to a washing system, consisting of a defoam trap and a scrubbing tower.
The goal at this stage is to perform an initial cleaning of the raw CO2 and remove possible entrainment of foam, soluble products, and other pollutants.
Compression, drying and purification
At this point the carbon dioxide undergoes compression and is sent to the actual drying and purification unit. Next, total removal of residual pollutants and water takes place by a combined high-pressure system.
Specifically, the drying system consists of two tanks in parallel that ensure the continuity of the plant operation: while one of the tanks is being adsorbed through a desiccant material, the other is being regenerated.
The purification unit, located downstream from the drying unit, is characterized by the use of regenerable carbons that are mainly responsible for removing odorous compounds through the same operating principle as the drying system.
Liquefaction
Once purified, CO2 from the gaseous state is brought to the liquid state at low temperatures. The liquefaction process is carried out through a closed-loop refrigeration system consisting of a low-temperature refrigeration unit, a liquefier, a reboiler and a stripping column.
In the liquefier, the gas is condensed through heat exchange with the refrigeration gas. The liquid CO2 produced, not yet pure, is sent to the stripping column, where it flows countercurrently with a stripping gas from the reboiler.
The liquid stream then arrives in the reboiler where the liquid carbon dioxide is partly heated in order to evaporate it and cause stripping gas to be created and flow down the column.
The combined effect of the stripping column and the reboiler serves to increase the purity of liquid CO2 and to remove non-condensable gases: in fact, the liquefaction step also has the task of totally completing the purification of CO2, bringing it to the required purity levels.
Storage, vaporization and reuse
Thus liquid CO2 is transported and stored in special tanks. When needed, it is sent from these tanks to an evaporator and reused in gaseous form for bottling beer and lager. The use of this technology has, in fact, the advantage of allowing bottling to be carried out with different timing from the fermentation process, making the two stages independent.
CO2 extraction, recovery and liquefaction plants: what benefits?
TPI’s Early Recovery, then, is the solution to produce high-purity (99.998%) CO2 locally from a “poor” source.
This CO2 recovery and liquefaction plant is optimized to ensure automated operation and continuous production, plus it has a compact design to make efficient use of space with custom-designed solutions tied to customer needs.
The benefits are obvious:
- cost-effective;
- respect for the environment;
- high flexibility;
- low consumption;
- Compliance with ISBT and EIGA guidelines;
TPI and CO2 plants: consulting, support and training
But that’s not all, Tecno Project Industriale has been involved in the Food and Beverage industry for decades and is among the world’s leading suppliers of CO2 treatment plants.
Therefore, thanks to this established experience, it can not only offer a full range of Turnkey CO2 recovery, extraction and production plants, but also a range of top quality, complementary services ranging from maintenance and supply of spare parts to Accordo sul livello di servizio complete, up to remote support, making use of specialized technicians, all with the aim of reducing operating costs and keeping the efficiency of partner breweries’ plants ate the highest level.
Learn more about TPI service delivery and contact the company for any further information.