In recent years, composting has become increasingly popular all over the world. Composting is the act of recycling organic matter into fertilizer for soil and plants and anything that naturally grows can effectively be decomposed into compost. A natural process of organic recycling creates a nutrient-rich substance from otherwise waste products such as banana peels or twigs. While composting might just sound like an alternative to recycling, it presents unique opportunities for industry and the environment. The EPA estimated that in 2018, 4.1% of wasted food, 2.6 million tons, and 25 million tons of municipal solid waste were composted, serving 6.1 million households the year prior. Furthermore, sustainable agricultural technology will be able to guarantee food security for many more individuals. By unpacking how composting is done, the benefits of composting, its industrial and home uses, and further related applications, this article will show how composting can contribute positively to sustainability efforts.
The Composting Process
At a fundamental level, composting requires a combination of greens, browns, and water. Greens are nitrogen-rich materials including leaves, grass, and food scraps, while browns are carbon-rich materials including paper, twigs, and leaves. The carbon provides energy through microbial oxidation at heat, while the nitrogen provides the nutrients needed for microbes to grow and reproduce. There is a delicate balance between the two, however. The ideal ratio of carbon-to-nitrogen is between 25-30:1 — too much carbon hinders microorganism growth and heat production, and too much nitrogen increases the acidity of the resulting compost while creating an ammonia smell. When exposed to bacteria and detritivores, these two elements remain within the original material and can produce healthy soil. Composting, while it may sound rather straightforward, has many different types, all of which involve changing the type of container, aeration, ratio of the three elements, and microorganisms. Doing so allows for different scales of composting.
On the larger scale, there is industrial or commercial composting. This process is designed to handle a higher amount of organic matter with a greater variety of inputs, including tough bioplastics. There are three primary techniques used — windrow, in-vessel, and aerated static pile. All closely monitored and dynamic processes, these forms of industrial composting are optimized with precise measurements and controlled conditions to ensure that the resulting product is toxin-free. From here, this large volume of compost can be sold to farms, applied to landscaping, or sold to other entities.
Even if there are not easily accessible industrial composting plants in one’s area, at home composting achieves the same effect, albeit on a much smaller scale, and thus should still be encouraged to further sustainability efforts. It is as easy as putting a pile together in the corner of the yard, or a small bin to host the waste. That said, generating ideal conditions for composting can be difficult. For example, fats, oils, dairy products, or meats cannot be composted at home simply due to the lack of sufficient heat. Further, these same products can potentially attract unwanted pests and generate offensive odours, and therefore must be monitored carefully on a regular basis.
The Benefits of Composting
Apart from the pure joy of recycling, composting is a relatively easy way to live more sustainably and can eliminate many environmental problems.
Primarily, waste management has become a pressing issue in the age of quick returns and general abundance. Organic waste from food and gardening alone make up over 28% of total waste, hurting both the environment and taxpayers. Unregulated decomposition releases methane and other greenhouse gases which contribute to climate change, a problem that global leaders devote substantial time and money to. Additionally, in 2019, the average cost to landfill municipal solid waste in the United States was around $55 per ton. The United States generates a startling 250 million tons of municipal waste annually, leading to a costly and inefficient use of taxpayer dollars. Composting can capture and eliminate around 99.6% of the volatile organic compounds present in waste which exacerbate many health risks and facilitate the effects of greenhouse gases.
Additionally, composting can prevent soil erosion and assist in water management. Compost increases the permeability of soil and binds the soil together with its high humus content, decreasing the amount of water runoff that would otherwise occur over the soil and slowing water flow in general. In relation to other fields, compost increases soil health and plant health. With its abundance of nutrients, compost both directly vitalizes soil in the form of nitrogen, phosphorus, and potassium, and can improve soil pH and nutrient retention, which further aids plants by naturally suppressing pests and diseases as well as other harmful weeds. Here compost can support greater sustainability in the agricultural industry, reducing the use of pesticides and unnatural fertilization in the long run. Financially, this would help lower production costs for farmers, increasing food security for millions, while creating additional composting-related jobs. In addition, composting can help aid reforestation, wetland restoration, and habitat revitalization through the remediation of contaminated and marginal soils.
Real World Applications
It is promising to see that composting has already been taken up by government and private agencies alike. While there is no national composting initiative in the United States, many state, nonprofit, and partnership environmental agencies have filled this gap. The EPA provides a comprehensive list of all of these agencies, many of which offer grant programs for organic municipal waste management or fund studies through university partnerships.
Privately, many solutions also exist. WasteNot Compost, a zero-emissions company that offers year round compost collection and processing, is one of many in the growing industry. They offer services to individuals, groups, and businesses in Chicago. WasteNot drop off five-gallon containers to fill during the week, and pick them up during the scheduled service date. For groups and businesses, they offer comprehensive and unique composting programs and aid, potentially providing composting certifications and landfill diversion metrics. Other similar companies operating in the United States include Reclaimed Organics in New York and Compost Crew in Washington DC.
While composting is among the lower-tiered options of the EPA’s food recovery hierarchy, it promotes a helpful mindset shift — paying more attention to what is bought and thrown away. Despite still being underutilized in the United States, foreign innovations in composting technology continue to broaden its potential uses. For example, it has been integrated into some toilet systems to use human waste to revitalize soil. As the applications of composting now extend past food recovery and waste management, we will see many new breakthroughs in the near future, possibly in the development of biodegradable plastics, and the improvement of all agricultural practices.