Trace4Value: Traceability For Sustainable Valuechains

Background

One of our biggest challenges in terms of sustainability and circular societies is to deal with the ever-increasing demand that agriculture and natural resources must meet the needs of the growing population. In this project we want to develop methods for recycling of nitrogen and other nutrients from various organic fractions in society, e.g. organic waste, wastewater and sewage sludge. These fractions have a high nutrient content, but effective techniques for extracting the nutrients (for example nitrogen and phosphorus) and returning them to food production are lacking today. In the project Trace4Value, we will evaluate different methods for extracting the nutrients and then use these as fertilizer in a vertical farm. Within the the project, we have built a test bed in a vertical farm located in DN-Skrapan in Stockholm.

Activities within the project

Within the project, we will evaluate different techniques for the extraction of nutrients from different waste streams. For example, we will carry out a number of experiments where we study different adsorption methods with different filter materials as well as pyrolysis and HTC. Wastewater, sludge and organic waste are provided by Mälarenergi AB, Eskilstuna Energi & Miljö AB, and VafabMiljö.

The potential for using extracts of nutrients and biochar in cultivation will be evaluated in a vertical cultivation, located in the DN scraper in Stockholm. The cultivation is run by the company Swegreen, which is also involved in the project. The supply of nutrients and water will be optimized so that the content of nutrients in the irrigation corresponds to the crop's needs.

We will evaluate methods for tracking and characterizing different waste streams. For this part, we will use real-time-based sensor technology with a so-called. "Multispectral camera". This camera measures the reflectance of different subjects, creating signals within specific wavelength spectra. We can translate these signals into interpretable characteristics, e.g. protein content, moisture content, growth, and the presence of plant diseases.

Project goals

• To find safe methods to reuse nutrient. Recycle nitrogen and other nutrients from organic fractions in society, e.g. organic waste, wastewater and sewage sludge. These fractions have a high nutrient content, but effective techniques for extracting the nutrients and returning them to food production are lacking today.
• Use the extracted nutrients in a local food production. For this we will use a so-called urban cultivation, located in the basement of the DN scraper in Stockholm. Since about 50% of fruit, vegetables and herbs today are imported from e.g. Spain, it is of high priority to increase the domestic cultivation of these crops. Sweden's climate makes it difficult to grow these outdoors, so urban cultivations indoors will probably become more important in the future. Within the project, we will create a closed cycle by reusing nutrients from the waste chain for local food production. Local crops are more nitrogen-efficient and can reduce the large losses that occur in today's conventional agriculture. It is therefore important to evaluate which fruits and plants are most suitable and have the greatest potential to be produced in local cultivation systems and which can be strategic (may be market dependent) or environmentally best to focus on.
• Convert organic material via thermal processes, such as hydrothermal carbonation to nutrients (especially nitrogen) and process heat which can then be reused. 4. Track nutrient content and any contaminants in the organic material upstream. This is important in order to be able to calculate the nutritional value and thereby control and optimize fertilization. It is also important to be able to detect any contaminants in order to be able to put in place purification measures if necessary.s from the society in a food production.