Typically captured carbon is stored in tanks or underground until required for use. However, Algaeneering’s brewery carbon capture design uses carbon dioxide to grow algae which is then processed into superfood tablets. Thus, unlike conventional carbon capture designs, Algaeneering is able to create a useful product to bring in extra profits for the Fahr brewery while providing a high-in-demand superfood for consumers.

Alberta produces more carbon than any other province in Canada so it is critical that the province finds ways to offset emissions. Alberta, along with many other Canadian provinces must abide by the federal carbon tax, which applies to all emitters that do not meet the federal standards. In the coming years, the carbon tax rate will rise will increase exponentially so Fahr beer can save money by eliminating their carbon dioxide byproduct and thus, the need to pay carbon taxes.

Tablet products are expected to have the fastest annual growth rate of 7.9% from 2021-2026 (IndustryARC, 2020). In addition, during the COVID-19 pandemic, consumers were searching for immune-boosting health products to lower their chance of contracting the virus, thus, amplifying the growth of the market in 2020. Next, the beauty industry uses algae proteins and supplements for their anti-aging effects and better maintenance of gut bacteria which can have beneficial results for dermal health and appearance. Lastly, changing lifestyle trends such as the increase of plant-based diets has shifted the preference for animal protein sources to plant protein sources, making chlorella tablets a highly sought after product.

The beer fermentation process is a biogenic process. It involves using barley and yeast to produce beer, but the yeast also produces large amounts of CO₂ as a by-product. Barley consumes CO₂ to grow, so many might say that beer fermentation is already a net zero process. With CO₂ being released back into the atmosphere breweries have an opportunity to capture and eliminate the CO₂ produced in the fermentation process, while continuing to eliminate CO₂ by growing the barley.

The intent of the implementation of this process is to reduce CO₂ emissions. In order to optimize the amount of CO₂ that is eliminated from the atmosphere we have designed a process that emits as little CO₂ as possible. This process contains equipment such as a heat exchanger, conveyors, and pumps that all require energy sources to operate. If we use electricity generated from natural gas, our process would not be as environmentally friendly as one may think, because electricity from natural gas releases a significant amount of CO₂ when the natural gas is burnt.

In order to ensure our process does not require electricity from a natural gas source we confirmed with our client that the electricity to the site, and that will be feeding our process, comes from wind power energy sources. In the future our client wants to produce their own electricity via solar panels, which is also an environmentally friendly source of electricity that does not release unnecessary CO₂ into the atmosphere.

Reactor Simulation

In the reactor kinetic simulations that were performed we found that if we decrease the total volume of fluid in our reactors, the temperature inside the reactors gets too high to support algal growth. We determined that a larger total fluid volume is necessary to avoid needing cooling jackets. We also found that culturing algae at a higher concentration allows us to require less reactors in our process (conserving space) and improves algal growth. Finally, we found that Chlorella vulgaris grows better with less dissolved CO₂.

Prototype

We have built a reactor prototype for our client to test and confirm all the values that have been determined, such as light intensity and photoperiods, cultivation amounts and periods and any other information that may be useful for our design. The dimensions of our prototype are 0.5m (L) by 0.03m (W) by 1m (H). The width was calculated with the Beer Lambert equation and the height was calculated using the Navier Stokes equation. The length is not dependent on anything other than the size of the facility that the reactor will be in, so an arbitrary value was chosen for the prototype. Acrylic glue was used to seal the acrylic walls together and 4 support pieces were placed in the center to keep the structure from caving inwards.

---

Our design has gone through many iterations in order to make it feasible. We came to the conclusion that we will be capturing 90% of the CO₂ emissions produced by the beer fermentation process of our client. Although the goal was to capture as close to 100% of the CO₂ emissions as possible, the feasibility of our design decreased exponentially if we were to exceed 90%. By graphing the rate of reaction against the conversion of CO₂, it was observed that the graph starts to increase exponentially at the 90% point, meaning that the growth rate of Chlorella vulgaris increases significantly at this point, which would require far too many reactors in our process. In order to maintain a feasible volume for our process, we made the decision to capture 90% of the CO₂ produced by our client, giving us a volume of approximately 15,500L, with 48 reactors containing 324L each.

Profitability Analysis

The profitability analysis includes calculating the gross profit margin and the net profit margin. The gross profit margin shows the percentage of sales revenue a company keeps after covering all operation costs and the net profit margin shows the profit generated for every $1 in sales.

The gross profit margin was calculated to be 73.2%. If the gross profit margin is higher than 65%, this is considered to be healthy, meaning that this company has more money to pay for indirect and other costs. The net profit margin was calculated to be 54.2%. If the net profit margin is over 10%, this is considered to be a high value, meaning that this company will be able to effectively control its costs and provide goods or services at a price higher than its costs. Since both the gross profit margin and the net profit margin are above the recommended values, this design is considered to be economically feasible.

Additionally, the cash flow shows that this company will start making a profit by 2025 and by the end of the predicted lifespan of the equipment, will have a net positive cash flow of over $7.8 million dollars, with an annual income of $580 thousand per year.

Sensitivity Analysis

As shown by the “Optimizing Reactor Conversion” plot in the previous section, a 90% reactor conversion was selected because the growth rate of Chlorella vulgaris increases significantly at this point, which would require far too many reactors in our process. A sensitivity economic analysis of the process is shown below to compare the nominal 90% conversion (mid-point on the plot) to conversions of 50% (much lower than the optimal conversion) and 95% (slightly higher than the optimal conversion). It can be seen that at 50% conversion, while costs are lower, so are the revenues and at 95% conversion, the increased costs outweigh the increased revenues.

Consumer Product Considerations

The Chlorella vulgaris tablets produced in this process are natural health products, therefore the production of these tablets must abide by the Natural Health Products Regulations which are a series of regulations under the Food and Drugs Act of Canada (Health Canada, n.d.). Fahr Beer will be required to apply and be granted a product and site license, before beginning the production process. The product produced in this process will contain only Chlorella vulgaris without any additives, or fillers. The tablet products will contain 500mg of Chlorella vulgaris and the recommended use will be to consume four tablets a day with a meal. Once Fahr Beer receives their license, they will be issued an eight-digit Natural Product Number (NPN), that needs to be displayed on the label of the superfood tablets. Apart from the NPN, the label will include the product’s name, ingredients, weight, recommended use, and instructions to store the container in a cool, dry place, away from heat or light sources. A warning on the label will indicate that the product is not intended for children under the age of 18 and that women who are pregnant or people with any known medical conditions should consult a licensed physician before consuming this product.

Process Design for Food Safety Regulations

In order to prevent any contamination in this process the heat exchangers, storage tanks, pumps, and settler units will be constructed using stainless steel and carbon steel, ensuring that surfaces are smooth, non-corrosive, non-absorbent, and non-toxic, to prevent pitting, cracks or crevices and the surfaces will be able to withstand repeated cleaning and sanitation (Canadian Food Inspection Agency, 2014). In the current process design, there are no cross-connections between potable and non-potable water supplies. All hoses, taps, and valves are designed to prevent back-flow or back siphonage. Recirculated water from condensate or for re-cooling will be monitored and maintained to prevent equipment corrosion. For any heating of equipment or heat exchanger units, the potability of steam that is in direct contact with food or food contact surfaces is controlled to prevent product contamination. The steam supply is sourced from potable water and meets operational requirements, furthermore, traps will be installed as necessary to ensure sufficient removal of condensate and other foreign contaminants.