Food waste is a global problem with a tremendous environmental impact. In 2018, the United States sent approximately 35 million tons of food waste to landfills. There, it decomposes in an anaerobic process that generates methane gas which is 87 times worse for the atmosphere than CO2. Landfills accounted for approximately 14% of methane emissions in 2017, making food waste a significant contributor to global warming. This recognition is driving the search for solutions for the proper disposal of commercial food waste.
Some states now require that organizations find alternatives for the disposal of food waste other than sending it to a landfill. This makes it even more imperative that organizations of any scale commit to finding less impactful ways of disposing of food waste. You should be aware of each solution’s unique advantages and costs before you make an investment.
Exploring alternatives to a landfill
As more people recognize the impact that food waste plays in greenhouse gas emissions, more governments and organizations have worked to identify solutions to the disposal of commercial food waste. For example, many commercial waste management organizations now offer hauling the waste to compost facilities or anaerobic digestion facilities.
However, solutions like this don’t necessarily account for the emissions created in the journey that the organic waste takes after it is discarded. This journey of the waste to a facility that is typically far from the business generating the waste adds cost and damage to the environment by the burning of fossil fuels.
The University of Nebraska-Lincoln recognized this when administrators began to follow the passage of waste from its dining halls. After food was dumped into the garbage can, custodial staff had to collect and move it into dumpsters. This messy job had to be performed several times each day. Later, trash was transported on trucks to a landfill, adding pollutants from the transportation on top of those created by the production of methane on the landfill.
Many organizations are taking a more holistic look at the factors leading to food waste, and in turn looking at the full impact of the disposal of organic waste. It’s for this reason that more companies are considering how they can dispose of this waste on site.
On-site options for food waste disposal
Once the decision is made to dispose of organic waste on site, organizations are faced with a range of different solutions. These systems tackle decomposition in different ways, each with their own benefits and potential drawbacks.
On-site disposal options include the following:
Dehydrators: Food waste dehydrators are machines that use heaters to evaporate moisture and agitators to shred the resulting food waste. The residual dried food waste is a brown powder that has 10 to 20% of the weight of the input. This can be used as a fuel source. Although some manufacturers of dehydrators call them “composters” and state the powder can be used as a soil additive, the powder is not compost and will create acids if buried in the soil.
Therefore, most facilities opt to transport the residual waste to the landfill (where it now creates methane). What’s more, it takes a significant amount of energy to dehydrate a feedstock that is at 70% to 90% moisture.
Composting: Composting creates an ideal environment for the bacteria, fungi, and other organisms to break down organic material. It is the oldest form to recycle organic waste, and it has long been deployed in backyards and agricultural sites as a means of creating material to benefit soil. Commercial organizations that compost, however, must have sufficient space to create the compost and then to use the resulting material.
Grinders: A grinder breaks down organic materials through grinding or shredding of those materials. The waste is discharged directly into the wastewater system. These systems are banned in most jurisdictions.
Biodigesters: A biodigester breaks down organic materials through the use of microorganisms and enzymes. There are two types of biodigesters: anaerobic (without oxygen) and aerobic (with oxygen).
The output from anaerobic digesters includes methane, that can be used as an energy source. However, most anaerobic biodigesters are typically large, offsite commercial facilities that accept organic material from a variety of sources.
Aerobic digesters can be installed in virtually any commercial food preparation space. Aerobic biodigesters create a waste product that is decomposed enough to be discharged directly into the wastewater system. In some cases, the filtered waste water can be used for irrigation.
The advantage of biodigesters
When considering the overall lifecycle of food waste, biodigesters emerge as clear winners due to their reduced environmental impact and long-term sustainability. First, the waste can be disposed of using existing infrastructure, without need for additional greenhouse gas-emitting transportation or other disposal of the remaining food products. In addition, aerobic biodigesters eschew the use of chemicals, instead introducing microorganisms to speed the natural decomposition of food. Some biodigesters can decompose waste foods within 24 hours.
However, there are other advantages that make biodigesters an ideal solution for the disposal of food waste. Most notably, organizations have reported significant cost savings simply by reducing the amount of time staff spends handling food waste.
For the Arthur I. Meyer Jewish Academy in Palm Beach Gardens, Florida, the installation of a biodigester led to cost savings of up to $5,000 directly attributable to the reduction in hauling solid food waste. The system paid for itself in less than two years. Ye Olde Fighting Cocks Pub in England saved more than $6,000 through its installation.
“The math made sense,” said pub owner Christo Tafelli of his decision to invest in a biodigester. “In the first week, I eliminated three food waste collections. Multiplied by 52 weeks, I spent $33,730 last year on overall waste removal with about 20% for food waste. That’s about $6,487 a year I’ll save.”
A holistic approach
With food disposal solutions increasingly being mandated by local governments, it’s important that organizations with on-site food preparation take time to understand the range of disposal options available. Food waste disposal technology is still comparatively new, but clear advantages are emerging.
To discover more about how an on-site biodigester can help your organization, contact Power Knot today.