Klimatpåverkan från byggavfall och alternativ återvinning

Sammanfattning: The construction and industrial sector are one of the most climate-affecting industries, regarding greenhouse gas emissions. In 2018 this sector contributed to more than a fifth of the total greenhouse gas emissions in Sweden. The same sector generates approximately one third of the total amount of waste. The government aimed to recycle or reuse 70 percent of non-hazardous materials by 2020. In reality, this figure landed at 50 percent, where the material is primarily recycled to extract energy and only a small part is reused. With Sweden's environmental goals in mind, the government has developed measures and new regulations to try to achieve these. These drive the construction industry to take responsibility and implement measures. It is seen that more and more construction companies are environmentally certifying their buildings, which shows that they strive to work towards a negative climate impact. Environmental certification of a building requires that the building meets certain set requirements. At the same time as they meet the requirements for environmental impact, the product must also maintain its qualitative properties. To answer the research questions, a literature study has been conducted to be able to answer whether there are alternative treatment methods for the waste and how to work to reduce the waste. An empirical study has also been carried out by collecting waste statistics and analyzing them to see which treatment methods have been used on the waste from the project and the amounts of the waste. With the help of the Boverket’s climate database, the climate impact was also calculated from four selected waste fractions. An analysis was carried out with the help of the Boverket’s climate database to compare what the climate impact from the waste would have looked like if other material choices had been made instead. The analysis showed that the product development phase (module A1-A3) contributes to the greatest climate impact of the A-modules. The comparative analysis between rock wool insulation against wood fiber boards and EPS foam plastic showed that wood fiber boards have a lower climate impact than both rock wool material and the foam plastic, but lower thermal insulation capacity and a slightly lower moisture resistance based on that the critical relative humidity is lower. The analysis showed that it is possible to reduce the climate impact of the waste by choosing other materials, but the materials have other qualities that benefit the building, such as the ability to isolate and resistance to moisture. The waste statistics show that 45 percent of the non-hazardous waste goes to the combustible fraction and that only the rock wool waste went to landfill. The climate impact from the rock wool that ended up in the landfill was 7,390 kg CO2-eq. Which is less than what the other waste fractions that were studied affected the climate with. The conclusions that have been drawn from this study are that too much material ends up directly for incineration into new energy, with the background to this study it should be sought that a larger percentage of the waste should end up higher up in the waste hierarchy. In addition, there are cost savings to be made if you can reduce the waste from the outset.