In the present and projected context of an increasing worldwide demand for food, the intensification of climate change effects on agriculture, and the depletion and degradation of natural resources, global actions must be taken to assure future food security for all people. Improper practices along the food supply chain, from primary production to consumption, generate huge quantities of food waste. Building a circular bioeconomy that feeds recycled materials back into the economy and minimizes the loss of resources will be an important step in introducing the world’s food system to a sustainable path. The present case study describes an enclosed on-site composting system for food waste, operated in real-life conditions. The composting equipment was installed for a restaurant with specific needs in November 2020, located near a shopping center in Bucharest, the capital city of Romania. The physical, chemical, and biological characteristics of the compost came from a mix of food waste from a retail restaurant and sawdust pellets used as absorbent material, and these were analyzed to monitor compost quality and establish valorization opportunities. Two different monitoring campaigns were developed and the biological parameters were analyzed. The second monitoring campaign indicated that the compost was contaminated with Escherichia coli and Salmonella spp. When handled correctly and according to instructions, the composting process eliminates pathogens that may be present in food waste, such as Escherichia coli, Salmonella spp., etc., resulting in a high-quality compost that can be valorized in agriculture such as fertilizer or soil improver. Our results demonstrated that even when maintaining the same composition of raw materials in the composter, the quality and properties of the compost are greatly influenced by its operating conditions. Quality management procedures must be enforced and procedures must be strictly followed for the compost to be considered compliant. Compost that does not meet the requirements according to the regulation in force is again subjected to composting. If, after repeating the operation, the compost is still noncompliant, it is declared nonrecyclable waste, and must follow the specific procedure for such waste.

Globally, the environment is the result of the interdependence between natural elements - water, air, soil, living things, and elements from human activity. Environmental pollution can be generally defined as the negative result of the domestic or industrial activity of any living thing that generates pollutants in the atmosphere or waste that reaches the ground or water. Numerous causes of pollution have made environmental protection one of the most important and essential problems in the world, pollution, and lack of protection measures affect people's quality of life. In this regard, the National Waste Management Strategy has been developed in Romania in 2019. This proposes a framework of measures to ensure the transition from the current development model based on production and consumption to a model based on the prevention of waste generation and the use of raw materials in industry, recovery, and recycling, thus ensuring the preservation of national natural resources. In this context, the current paper illustrates the achieved results from the experimental activities carried out using a closed composting system, that is a mobile one. The input materials in the composting process were sludge from a municipal wastewater treatment plant (26%), market waste (vegetables and fruits - 18%), and wood chips (56%). The results showed that, for the analyzed heavy metals, the concentrations in compost do not exceed the limit values for the second category of compost according to the Romanian regulation in force (Law 181/2020 - on the management of non-hazardous compostable waste). Consequently, the obtained compost from a mixture of sludge from the wastewater treatment plant, waste from the market (vegetables-fruits), and wood chips can be used on agricultural land.