Comparing drying and vermicompost methods to reduce food waste in apartment space; move toward the reduction of environmental crisis by food waste management at sources.

Today, much food is lost by population increase and the expansion of consumerism. Food waste is one of the major environmental problems, which introduces a large number of greenhouse gases and leachate into the environment. Food wastes in Iran are deposited without the necessary control management. Numerous studies have shown that often foods are lost at the level of consumption. Managing food waste at the source has many social and economic benefits, and it is an important step in reducing climate change and global warming. It seems that vermicomposting and drying are two methods that can be used for food waste management. In the vermicomposting method, earthworms decompose organic materials and turn them into earthworm casting. In the drying method, food wastes completely lose their moisture, volume, and weight.
In this study, vermicompost and drying methods were compared to find out which method is easier and more practical to manage food waste in an apartment space. A vermicomposting box containing 300 Eisenia fetida earthworms was used for the vermicomposting method, and perforated baskets were used to dehydrate food waste in the open space, exposed to sunlight and airflow for the traditional drying method. The results were shown that external factors such as the amount and type of food waste, initial moisture content, and temperature had a direct effect on the performance of earthworms and the speed of decomposition of food waste. When the initial moisture in vermicompost was controlled, it did not produce a lot of leachates and bad smells. This process took three months, it is usually long. Vermicompost fertilizer was produced as a final product, which is full of nutrients for plant growth. The drying method took a short time, between two to three days. When the temperature and airflow were high and the initial moisture and thickness were low, the food waste dried faster and in a short time. Traditional drying methods attracted many insects which were troublesome. Dried food waste completely lost its moisture. Their volume and weight were significantly reduced and it was easy to keep them at home for a long time. Dried wastes were used for feeding livestock. Traditional drying costs much less than vermicomposting but occupied more space than vermicomposting. Both methods were easy and practical for the apartment space. According to the conditions, households can use either of these methods or both methods to manage and reduce food waste at home.