Producing high quality barbeque charcoal and biochar in a fraction of the time taken by traditional ring kilns. Carbon accounting for compost use in urban areas. publisher of BioCycle CONNECT & Biocycle.net | P.O. Carbon credits/debits were estimated both on a per ton of compost basis and a per ton of biosolids basis. The secret to producing high quality compost is to maintain the right proportion of carbon and nitrogen materials. For example, new lawns likely have poor soils, in part due to loss of topsoil during construction. Using a car to pick up 50 kg (110 lbs) of compost generates 0.09 Mg CO2/ton of compost. These microorganisms (which we also call “microbes” at random through this site) require four basic things to help them create the rich, organic compost we use in our gardens. The brown materials provide carbon for your compost, the green materials provide nitrogen, and the water provides moisture to help break down the organic matter. Tear it and mix it with fresh manure or grass clippings, or lay it on the bottom of a pile if you’re composting in a damp region. Greening up your highways can provide lots of carbon credits. The average long-bed pickup truck can hold 64 cubic feet of material, which is the same as a 4’x4’x4’ compost pile. Also, brown materials help … Break, chop, and shred this material as much as possible to speed decomposition. Woody plant trimmings: Shrubs, trees, palm fronds, dead perennial stems, Brussels sprout stalks, and dried cornstalks all fit into this category. This would make a feedstock combination that was about 30% biosolids on a dry weight basis. Grass trimmings are the quintessential compost ingredient. The peer review literature was used to estimate carbon debits/credits for growing lawns, trees, urban agriculture and for use alongside urban roadways. (Note: 1 Mg=1 ton). They highlight the good and the bad, where applicable. Results from specific end uses are shown in the series of tables below. The underlying soils for both lawns and trees will respond to compost addition and store carbon. Unfortunately, there isn't a good source of carbon in my mostly-lawn garden. For turf, you get credits for soil carbon and not using fertilizer. To put the findings for the compost basis vs. the biosolids basis into perspective, it is important to consider the quantity of biosolids in a dry ton of compost. It is used, for example, in gardens, landscaping, horticulture, urban agriculture and organic farming. You should also alternate layers of organic materials of different-sized particles. The main job of browns in a compost pile is to be food sources for all of the lovely soil-dwelling organisms that will work with the microbes to break down the contents of your compost pile. Don’t worry about pine needles’ acidity unless you have a lot of them: Small amounts have minimal effect in your compost pile or soil. Compost is rich in nutrients. Brown materials such as leaves, straw, hay and sawdust are high in carbon and are a source of energy for the compost microbes. Carbons for the compost pile include the following: Dry leaves: Dry leaves are probably the easiest brown ingredient to work with for a beginning composter because they’re already smallish pieces of organic matter that are easy to shred into even tinier pieces if you choose. Carbon emissions vs. reductions of King County’s current biosolids program looks like this (see figure to right): Even though the haul distance to dryland wheat fields is very high, the county’s biosolids are transported using high capacity vehicles, lowering the per ton carbon footprint associated with transport. The Organics Recycling Authority
Over the course of a year or so, the material will decompose. This means you will need 42-48 cubic feet of carbon materials for one 4’x4’x4’ compost pile. Each features mixes of the variables. Thick layers of sawdust compress into impenetrable mats, reducing the ability of oxygen and water to circulate through the pile. Structure and Oxygenation. Transport in urban areas is much less efficient than long haul trucking. The closer you can come to mixing up 3 parts carbon materials to one part nitrogen materials when you build your pile, the faster the decomposers will consume it and reward you with finished compost.