Dumpsters are brute workhorses in waste management. Made stout, with long service lives, repairable, and made affordable due to their simple and repeating design. All those features make them a perfect host vessel for in-vessel composting where converting a waste stream into a valued agricultural product can occur within a month鈥檚 time.
By Tim Shuttleworth
Waste disposal companies are often searching for the highest value use of their assets, including their fleet of dumpsters, in order to earn the highest return on their investment. Dumpsters have more value to add than waste hauling alone, they can also host a value-adding process. Composting, like dewatering, is a value-adding process where a foul waste stream is converted into a valued agricultural product. New composting technology enables ordinary roll-off dumpsters to be used as advanced in-vessel composters.
Articles in 国产麻豆 have covered both advanced composting (June 2022) and the use of dumpsters for a 鈥減rocess purpose鈥� such as dewatering (March 2022) rather than only for waste hauling. This article unites both of these topics by highlighting a new technique wherein the common roll-off dumpster becomes an advanced composter of organic waste when a novel aeration apparatus, supplied as a drop-in 鈥渒it,鈥� is hosted by that otherwise common roll-off dumpster. This use of a dumpster requires no modifications to the dumpsters themselves. After a period of use as a composter, they can immediately return to waste hauling. No customization is required for the installation of the composting apparatus.
Photo courtesy of Dungster LLC.
Why Bother to Compost?
Compost renews and rebuilds our soil and is an environmentally responsible step to mitigate water pollution, air pollution, and the production of greenhouse gases. Some organics, such as manure are regulated, so composting them is the only feasible disposal option.
Compared to landfilling, composting is a 鈥済reen鈥� and earth-friendly processing step and is far superior. If organics are simply landfilled there are several negative aspects, including:
1. Disposal fees can be substantial.
2. It takes up valuable landfill space. Diversion from landfill is a worthwhile objective standing alone.
3. It is a loss of nutrients and carbon we need to renew our soils
4. It is expensive to transport manure and other organics to landfill locations and
5. It will anaerobically decay in the landfill producing methane and other gases that are very damaging to greenhouse gases.
Composting is an economic 鈥渨in鈥� as a waste/liability is converted into an asset that can be sold by the cubic yard. Several new laws prohibit food waste from being landfilled. After rescuing the food for either human or animal consumption, composting is the next best option.
In-Vessel Composting
One composting technique is called in-vessel composting1; it is this technique used by this novel process. In-vessel composting creates a bioreactor and, therefore, has real merits over other composting methods, such as aerated static piles composting, because it is very stable and repeatable. The repeatable X, Y, and Z dimensions of a commercial dumpster, when a made for the purpose of cover is added; this means that the organic feed materials are always confined in a known, uniform, and repeatable cubic volume. This also keeps the composting apparatus standardized to keep the cost of this approach more affordable as mass production can be used. The mass production of the common dumpster likewise helps to keep the total cost of this approach to a minimum.
Scale and a Scalable Solution
This composting volume, of say 10, 20, 30, or 40 cubic yards of a dumpster, is a fraction of the commercial volumes using other methods. This means the composting can be done at or near the source of the organic waste and the need to haul and combine materials from multiple sources is avoided. Often the finished compost can be used or sold where it was generated. When volumes increase and decrease, such as due to seasonality, the census of dumpsters can vary likewise. Certainly, dumpster composting is a niche in the composting world and will not crowd out commercial composting operations. For users, it is a valued niche. Waste food can be nasty as anyone cleaning out a refrigerator knows. 鈥淣asty鈥� does not scale up and well 鈥� it is a classic case that 鈥渓ess is more.鈥� Material handling steps, transfer stations, and hauling and combining all add time and yuck to the food composting process. It is best to keep the batches small and near the organic鈥檚 origin.
The Aeration Apparatus Installation
Building upon the stable geometric footprint of roll-off dumpsters, the delivered aeration apparatus, a 鈥渒it,鈥� converts a common dumpster into an in-vessel composter in about one-hours鈥� time. This aeration apparatus simply unfolds, slips together laying by gravity alone in the bottom of a standard roll-off dumpster, making that roll-off a temporary composter. As mentioned before, this quick and temporary installation requires no drilling, welding, or other permanent modification to the dumpster. No tools are required. A small timer control is positioned nearby in a dry space using a weather-proof extension cord to deliver power. Or, if solar powered, solar panels, integrated into the top cover feed power to a battery and control enclosure. There are no moving parts aside from a blower, which mounts to a vertical pipe rising from the aeration system laying in the bottom of the dumpster. With the aeration kit laying on the bottom surface of the dumpster, the dumpster is filled with the organics (food waste, manure, etc.) to be composted and the control is switched on. The control intermittently turns on the fractional horsepower blower mounted on the vertical pipe dosing air into the dumpster (now a composter). The blower runs a few percent of the time and is off more than 90 percent of the time. Electricity costs are therefore minimal. The temperature will naturally rise and stabilize in the range of 100oF to 160oF degrees. For reference, this is warmer than bath water and cooler than a fresh cup of coffee. After a period of about a month鈥檚 time, the organics will have been composted, and the aeration kit is then extracted for reuse. The finished compost can be emptied at the composting site or delivered and dumped at another location.
Controls Can Be 鈥淏arebones鈥� or 鈥淐loud-Connected鈥�
To keep this composting option affordable and simple-to-use, a small two-knob control unit is the entry-level control system. Manual temperature monitoring and a little coaching by the supplier and a new user is off to the composting races. A more advanced cloud-based control is also available to monitor the composting process. This control will upload data and monitor the process intervening to make corrections if necessary. On periodic intervals, the temperature data is uploaded to document that pasteurization has occurred (temperatures above 131oF were reached and maintained). This advanced control will also 鈥減ush messages鈥� to the user鈥檚 smart-phone鈥攆or example, if system power is lost.
A Mobile Solution
Part of the usefulness of the roll-off dumpster, when used temporarily as a composter, is that dumpsters are designed to be mobile and to be 鈥渄umped.鈥� This means that after the aeration kit is extracted from the finished batch of compost, the material can be transported from a source point to a use point in the same vessel (the same dumpster). The transport step, as well as the rental of the dumpster, can be a part of the waste disposal company鈥檚 value proposition. That is, the delivery of goods (rather than the removal of waste) and even the value of the goods. Compost is sold by the per cubic yard.
Neither the feedstock nor the finished product (compost) has any lasting effect on a dumpster. As previously discussed, during the composting process the elevated temperature not only converts the materials physically, but it also 鈥渟anitizes鈥� the materials by a process called pasteurization. What was initially animal excrement or food waste becomes rich compost. Weed seeds ingested by the grazing animals no longer can sprout and any pathogens or insect larvae present are also killed by the elevated temperature. Composting temperatures will effectively pasteurize the material into a new, safe, stable, and usable product. This is the same broad process used to treat municipal waste.
Dumpsters are brute workhorses in waste management. Made stout, with long service lives, repairable and made affordable due to their simple and repeating design. All those same features make them a perfect host vessel for in-vessel composting where the valuable work of converting a waste stream into a valued agricultural product can occur in a month鈥檚 time when advanced technology is laid in the dumpster to do its work.| WA
Tim Shuttleworth is the founder of Dungster LLC. He is looking for disposal companies with a fleet of dumpsters who would like to be agents or distributors of the Dungster LLC鈥檚 composting method. Your dumpsters, fitted with Dungster鈥檚 composting kits, can make compost, and make a positive impact on the environment. For more information, e-mail [email protected] or visit .
Notes
1. https://en.wikipedia.org/wiki/In-vessel_composting
2.https://pacd.org/wp-content/uploads/2025/01/PotterSummit-Trail-Rides_final.pdf
3. www.biocycle.net/lower-tech-containerized-composting/