Each year, the coffee machines at Ericsson in Kista produce around 100 tons of ground coffee waste. The companies Coor Service Management, Löfbergs Lila and Selecta are all responsible for different stages in the logistical chain in delivering coffee and, together with Ericsson, they want to increase their environmental benefit. The plan is to produce biogas through anaerobic digestion instead of incinerating the coffee waste in a heating plant. The results are to be presented as different business cases in which different biogas plants are compared with the reference case (heating plant), comparing costs and environmental impacts. There are two major environmental benefits from producing biogas; reduced carbon dioxide emissions from when fossile fule is replaced by carbon neutral biogas, and reduced emissions from returning digestate from the bio reactor to farmland instead of using industrial fertelizer. In order to determine the biogas potential in coffee waste, a couple of properties had to be determined in a laboratory. Properties such as the dry substance content, heating value, moisture content and ash content. The results show that 100 tons coffee waste could produce around 16 500 Nm3 biogas which would contain 163 MWh. The biogas reactor and upgrade plant both need energy gas to function and uses around 14 MWh of the produced gas. In the end, the resulting upgraded biogas contains 149 MWh energy. Such an amount of gas can replace 15,1 m3 of diesel and thus reduce carbon dioxide emissions by 39,4 ton. The emissions from running the reactor and upgrade plant, combined with methane leakage amounts to 4,8 ton carbon dioxide. All of the biogas plants that were examined returns digestate and nutrients to farmlands which reduces the need for industrial fertelizer. The production of fertelizer uses alot of energy, and by returning digestate a reduction of 58 GJ energy and 3 ton CO2 can be achieved. This is not the case with the heat plant which instead has to place some of its produced ashes in landfills. If the exergy content in the biogas is compared to that of the heat it shows that there is a point to making gas instead of incinerating the waste. The biogas has about 50 % higher exergy content than the heat has and therefore it is possible to utilize the substrate more efficiently. Transporting coffee waste from Ericsson to different biogas plants will result in increased carbon dioxide emissions. The three plants investigated in this thesis are Henriksdals sewage treatment plant, the Himmerfjärd plant and Uppsala biogas plant. For each plant, drivning distance, pre treatment requirements of the coffee waste, and related costs were determined. Using methods from the Network for transportation and enviroment, the emissions for each case were calculated. The results show that the Henriksdal case will increase carbon dioxide emissions by two tons per year, and the other cases will increase emissions by four tons. The result from combining laboratory work, simulations and calculations show that the case where Henriksdal recives the coffee waste will reduce carbon dioxide emissions by 15,1 ton at a cost of 72 000 kr per year. The case with the Himmerfjärd plant will reduce emissions by 13,8 ton at a cost of 74 000 kr per year. The final case with Uppsala biogas plant will reduce emissions by 13,7 ton at the cost of 107 000 kr per year. And thus there are environmental benefits from producing biogas from the coffee waste, but they do come at a cost.

Circular economy is an economic model that is gaining more and more attention, themodel aims to close production chains by recirculate waste into the system as newraw material. Spent coffee grounds are a waste that has great potential to becomenew products since the spent coffee ground contains many valuable substances suchas polysaccharides, polyphenols, and lipids. Swedes are the sixth largest coffeeconsumers per capita in the world, which means that large quantities of coffeegrounds are produced in the country. Therefore, the purpose of this report is toinvestigate possible ways to valorize spent coffee grounds in the municipality ofStockholm, as an alternative to the treatment processes that exist today. Toinvestigate this, the main methods have been a literature review, a field study andeconomic analyses based on existing data. The results show that from 5 large coffee-shop chains in the municipality of Stockholm, approximately 138,477 kg of coffeegrounds can be collected each year. Furthermore, it shows that five differentmethods for extracting polysaccharides, polyphenols, biochar, oil, and protein fromspent coffee grounds have been effective and that these substances and products canbe used in, for example, the food industry, in cosmetics, as plastics and asadsorbents. The economic assessment shows that biochar, polyphenols, and oil arethe compounds and products that are economically profitable to extract, and theycan give a maximum profit of SEK 482.28/kg of spent coffee grounds. The resultsare consistent with previous research on the subject, but there are someuncertainties in the exact figures as there is a lack of economic analyses for spentcoffee grounds in the previous research. However, the results show great potentialfor spent coffee grounds in a circular economy, but further research is required toensure the economic gain. In addition, analyses need to be done on the ecologicalsustainability and more studies need to be done on coffee grounds in Sweden tovalidate the results. / Cirkulär ekonomi är en ekonomisk modell som får mer och mer uppmärksamhet,modellen syftar till att sluta produktionskedjor genom att återinföra avfall som nyttråmaterial. Kaffesump är ett avfall som har stor potential att bli nya produkter pågrund av att sumpen innehåller många värdefulla ämnen som polysackarider,polyfenoler och lipider. Svenskar är de sjätte största kaffekonsumenterna per capitai världen vilket gör att stora mängder kaffesump produceras i landet. Därför är syftetmed denna rapport att undersöka möjliga vägar för att värdesätta kaffesump iStockholms stad, som alternativ till de behandlingsprocesser som finns idag. För attundersöka detta har de huvudsakliga metoderna varit en litteraturstudie, enfältstudie och ekonomiska analyser baserade på befintliga data. Resultaten visar attfrån 5 stora kafékedjor i Stockholms stad kan cirka 138 477 kg kaffesump samlas invarje år. Vidare visar det att fem olika metoder för att utvinna polysackarider,polyfenoler, biokol, olja och protein ur kaffesump har varit effektiva och att dessaämnen och produkter kan användas inom exempelvis livsmedelsindustrin, ikosmetika, som plast och som adsorberande material. Den ekonomiskabedömningen visar att biokol, polyfenoler och olja är de ämnen och produkter somär ekonomiskt lönsamma att utvinna och de kan ge en maximal vinst på 482,28kr/kg kaffesump. Resultaten stämmer överens med tidigare forskning på ämnet mendet finns vissa osäkerheter i de exakta siffrorna då det saknas ekonomiska analyserför kaffesump i den tidigare forskningen. Resultaten visar dock på stor potential förkaffesump i en cirkulär ekonomi men vidare forskning krävs för att säkerställa denekonomiska vinningen. Dessutom behöver analyser göras på den ekologiskahållbarheten och fler studier behöver göras på kaffesump i Sverige för att valideraresultaten.