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Food waste, yard trimmings and other organics make up over a third of the material, by weight, that we manage for our customers. Wasted food is a major economic and environmental challenge across the globe.
The U.S. EPA estimates that yard trimmings and food waste account for more than 33.7% of total municipal solid waste generated, and when factoring in the energy used to grow, process and ship food, as well as the emissions released when it decomposes, food waste adds billions of tons of GHG emissions to the atmosphere.
While the concept of a circular economy is most often applied to manufactured goods, it also applies to organics, including food. The benefits of managing food and yard waste at end of life are significant—and businesses and governments are taking action.
Where possible, WM helps prevent food from being wasted and encourages its redistribution through local food donation programs. For other organic material, we continue to invest in new or expanded programs for handling at end of life. Although the pandemic significantly slowed or halted food waste programs and municipal project development related to organic waste, WM continued to invest in new organics processing capabilities to meet our customers’ needs.
Preventing food waste upstream benefits the environment in terms of emissions reduction and helps communities in need by providing nutrition that would otherwise go unused. When possible, WM works with companies and municipalities to donate unused food to food banks before it gets thrown away.
Compost as a Soil Amendment Solution
Composting and mulching are proven, low-cost solutions for managing large volumes of organic materials, particularly yard waste. WM has facilities that process organic material into compost and mulch, as well as new organic solutions developed in collaboration with customers. Compost products are used to improve soil structure and quality by supplying macro- and micro-nutrients and beneficial microflora. The high amount of organic matter in compost also increases soils’ capacity to hold water. This is particularly important in areas where drought conditions make water a precious resource. Much like the recycling process, WM’s composting services help create a closed loop: food and yard waste become compost, which in turn helps feed the next season’s crops.
We process yard waste and food waste into compost using a variety of methods including the windrow method and the covered aerated static pile method. The method chosen is based on permitting, space, cost, climate and other variables.
Inside a Windrow Compost Facility
Food and yard scraps are transformed into a mixture that resembles rich, dark soil, ready to deliver to customers. Here’s how the process unfolds.
Yard waste and food waste arrive in commingled form, from a variety of sources including commercial, residential, municipal and industrial customers. After sorting to remove contaminants, the organic material is formed into long piles, called windrows, which generate heat as microorganisms break down the organic matter. Machinery turns and mixes the piles, incorporating air that helps in the decomposition process. Temperature and moisture are carefully monitored, ensuring that the natural process can unfold regardless of weather conditions. The compost is passed through screens that create a product with a consistent particle size.
CORe® Organics Processing
CORe® is WM’s proprietary organics recycling process that converts food waste into EBS®, an organic slurry product used to generate green energy.
Through , we collect commercial food waste from restaurants, schools, food processing plants and grocery stores, screen it to remove contaminants such as plastic, packaging and bones, and blend the waste into an engineered slurry. The slurry is injected into treatment facility digesters in existing wastewater treatment infrastructure. This process increases the biogas produced by the digester by as much as 90% without notably increasing its residual digestate. This gas can then be used as a renewable power source.
The WM CORe® Process
Adding additional organic material in the form of engineered slurry to anaerobic digesters in a water treatment plant typically increases energy output from 50% to 100% or more.
- WM’s CORe® process is a local, urban solution that converts food material into our EBS® product through our proprietary process.
- EBS® is a high-quality, consistent product, removing more than 99% of the physical contaminants found in urban waste.
- The EBS® product is used to create renewable, sustainable energy helping local partners approach zero-waste.