Circular economy for breweries : utilising brewery wastewater for growing hydroponics hops
Basnet, Mukesh (2022)
Diplomityö
Basnet, Mukesh
2022
School of Energy Systems, Ympäristötekniikka
Kaikki oikeudet pidätetään.
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi-fe2022102062622
https://urn.fi/URN:NBN:fi-fe2022102062622
Tiivistelmä
This research is a novel approach to finding solutions for breweries to move towards sustainability by recovering nutrients from their wastewater to produce organic liquid fertilisers for growing hydroponics hop plants that can yield dry hops demand necessary for their beer production. Hops is one of the main ingredients used in beer production that determines the quality of beer and brewers usually use dry hops in the brewing process. The assessment done in this research is the first of its kind for the brewery industries, no previous research about it has been done earlier. The potentiality of three Finnish breweries' (Hartwall, Sinebrychoff, and Laitilan) wastewater has been evaluated in this thesis by conducting research on nutrient availability in the breweries' wastewater and assessing if those nutrients are sufficient for producing organic liquid fertiliser to grow hydroponics hop plants in a large scale.
The findings of this research show that when the dry hops use is in small quantity, for example, 2 g/L of beer produced, then most of the nutrient quantity in breweries' wastewater is sufficient to produce annual dry hops demand for beer production. For example, in the case of Hartwall brewery, when the dry hops use is 2 g/L of beer produced, the necessity of buying artificial N, P, and Zn fertilisers can be replaced by about 74%, 156%, and 230% respectively. But when the dry hops use is 12 g/L of beer produced, the replacement of artificial N, P, and Zn fertilisers are about 12%, 26%, and 38% respectively.
The environmental benefits that can be achieved by the recovery of nutrients from the brewer’s wastewater are reduction in carbon footprint by less CO2e emissions of about 400 to 146 000 kg CO2e, that will otherwise be emitted by the application of artificial N and P fertilisers to produce hops; about 95% of less demand of land area by land use change from soil-based hops farm to hydroponics hops farm; fewer GHG emission by becoming self reliant in hops and fertilisers demand; reduction in spillage of fertilisers into the sea due to fewer shipment of them, thus less contribution towards the eutrophication of the sea, such as Baltic Sea; reduction in water footprint by reusing treated wastewater that is generated after production of organic liquid fertiliser; and preservation of non-renewable resources of fertilisers such as phosphate rock. Simultaneously, breweries will be profited economically by becoming self-sufficient in the dry hops demand to meet their beer production.
The findings of this research show that when the dry hops use is in small quantity, for example, 2 g/L of beer produced, then most of the nutrient quantity in breweries' wastewater is sufficient to produce annual dry hops demand for beer production. For example, in the case of Hartwall brewery, when the dry hops use is 2 g/L of beer produced, the necessity of buying artificial N, P, and Zn fertilisers can be replaced by about 74%, 156%, and 230% respectively. But when the dry hops use is 12 g/L of beer produced, the replacement of artificial N, P, and Zn fertilisers are about 12%, 26%, and 38% respectively.
The environmental benefits that can be achieved by the recovery of nutrients from the brewer’s wastewater are reduction in carbon footprint by less CO2e emissions of about 400 to 146 000 kg CO2e, that will otherwise be emitted by the application of artificial N and P fertilisers to produce hops; about 95% of less demand of land area by land use change from soil-based hops farm to hydroponics hops farm; fewer GHG emission by becoming self reliant in hops and fertilisers demand; reduction in spillage of fertilisers into the sea due to fewer shipment of them, thus less contribution towards the eutrophication of the sea, such as Baltic Sea; reduction in water footprint by reusing treated wastewater that is generated after production of organic liquid fertiliser; and preservation of non-renewable resources of fertilisers such as phosphate rock. Simultaneously, breweries will be profited economically by becoming self-sufficient in the dry hops demand to meet their beer production.