Composting: It's Not About If but When and How (Part 1)
Food scraps are being wasted and filling up our landfills when they could be going to building soil and growing our food. Plants thrive on compost, and we have the technology to make composting easy and efficient, yet we choose not to.
In my next two articles, I will explore composting, the latest technology, and how we can get it done.
What is compost?
Compost is basically the byproduct of anything that is biodegradable. Composting is a digestive process not much different from the digestion in our stomachs. Basically organic matter is consumed by microscopic organisms, just like in our guts, and the byproduct is compost.
The main focus of compost for agriculture is composted animal and food waste. I am going to focus mainly on food waste in these articles. Food waste can be divided into two categories, pre- and postconsumer waste. Preconsumer waste is prep scraps from the kitchen before the consumer touches it, and post- would be leftovers after a meal has been served.
For the home gardener and novice composter, you will deal only in preconsumer vegetable scraps, leaving out any meat, dairy, and oils. The reason for this is that with postconsumer waste, temperatures need to be closely monitored and raised to kill pathogens that could be transferred to our crops.
Most people think that the heat from the compost pile comes from the pile sitting in the sun, but it is from acids that organisms release to break down scraps. This is accomplished only by having a composter with an inside volume of at least three cubic feet.
Waste Stream Analyzed
While working at the Breakers Resort in Palm Beach, we did an analysis of the waste stream from the main trash collection for the hotel, which included the banquet kitchen. This day was disgusting but a necessary exercise for the greater good. The average annual waste from this site is 1.2 million tons.
In this study, we separated waste into three categories: landfill, recycle, and compostable. All day, we dumped out all trash cans onto tarps, separated, measured volume, weighed, and recorded the data, of course with clothespins on our noses. It was shocking what we discovered! We found that 54 percent of the total waste could have been composted and turned into fertility to grow our food. These are big numbers but just a drop in the bucket with regard to our total waste stream.
While on a research trip, sponsored by the Breakers, to Napa and Sonoma Valley, California, I was amazed to see by the curb on trash day four cans at each house. The cans were color-coded and lined up: landfill waste, recyclable paper and plastic, yard waste, and food scraps. The smallest can was the landfill waste. California sets the standard; why we are not composting already is crazy to me.
Composting Options for Large Scale
So, with more than half of our waste stream that can be recycled and turned into something we can use to grow plants, we need to now figure out how to get it done. Mother Nature has given us many options with regard to methods of composting we can use to get it done, and then we must select equipment to use.
First, figure out which type of composting is right for you. Here are the options: vermicomposting (uses worms), soldier fly composting (uses fly larvae), aerobic composting, or anaerobic composting.
For this article, we are going to only talk about aerobic composting, which means the organisms we are going to use breathe oxygen and let out carbon dioxide. Aerobic compost is the type of composting everyone is accustomed to seeing, but there are numerous ways to do it and different types of equipment to use. The types I will talk about here are static pile and tumbler composting.
Static pile is, as the name implies, a pile that is left to decompose; the time frame can be sped up by turning the pile to get oxygen inside (like a fire that is smoldering out), the process can take three months to a year.
A tumbler is like a cement mixer that slowly turns. Tumblers are very fast; typically one-third of the capacity can be harvested daily. (Yes, daily!) These units come in various sizes, from 1 cubic yard (capacity of a small pickup truck bed) to 96 cubic yards (the size of an 18-wheeler trailer).
My advice is to choose the type that will consume the waste at the speed you need it done, using the space available. For instance, if you are like the Breakers with 1.2 million tons annually, static pile will take an enormous amount of land to pile the compost. A tumbler uses a small amount of space and digests much faster; therefore, it would be the better choice.
Check back later this week for the conclusion and an in-depth look at a compost tumbler.
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