Waste to Fuel
Today's waste products can be tomorrow's fuel sources
With the ever-increasing prices of gasoline and diesel fuel people have been looking around for alternative fuels since the first fuel crisis in the 70s drove the price of fuel over $1.00 per gallon. In the last 15 years the straight vegetable oil (SVO) fuel hobbyists have proven that vegetable oil is a viable diesel fuel source. Once it was understood that vegetable oil would burn in a diesel engine it was not long before these vegetable fuel hobbyists started tapping into the tallow bins behind local restaurants for their source of fuel.
The successes of the SVO hobbyists have inspired others to look around for alternative fuel sources, and the idea of expeller pressing oil from agricultural wastes became an obvious source of vegetable diesel fuels. While extracting one's own fuel oil from seed is hardly economically feasible for the individual to do, it is however, far easier to press oil from seed than it is to refine gasoline (petrol) from crude oil. As a technician in the 70s and 80s I was in fact involved in both processes, and I saw the refining of crude oil into fuel is far more involved technologically, economically and environmentally than it is to run an expeller press to extract oil from seed.
To make an expeller press operation economically feasible one would have to, however, be pressing tons of seed to extract hundreds of barrels of oil. If one were prepared to do that then one could conceivably make expeller-pressing oil from seed a worthy business venture.
The first thing that one would have to locate is a reliable and economically feasible source of usable seed. I have been looking at cottonseed here in Southern Arizona as such a fuel source. Every cotton gin has an old expeller press that they used for extracting cottonseed oil before the cholesterol scare and the rapeseed industry put them out of the cooking oil business. In Southern Arizona we have tons of seed going to waste and expeller presses rusting away and all we need is an SVO economy to tap into. Unfortunately the regional SVO economy is not there yet, but it is close.
Anyone in the business of pressing oil from seed would also want to find an economical way to dispose of the residues of the seed-oil pressing operation. The disposal of cottonseed press-cakes is rather easy, one need only sell the cottonseed press-cakes to the animal feed industry, which is thriving regionally, and used to buy the cottonseed press-cakes in the 60s and 70s when it was available.
If one has access to an oil bearing seed, such as soybeans, and one was interested in extracting hundreds of barrels of oil from them, then one would also want to look into what could be made of value from the soybean press-cakes. Soybean press-cakes could easily be made into low-fat tofu, soymilk and soy protein powder. If there is still residue after these processes, then one could sell that residue to the animal feed industry, or ferment it into alcohol as a fuel source, or compost it.
We can learn a lesson from the sesame and peanut industries. Sesame and peanut oils have been valuable commodities for a long time. The sesame oil makers have been making the confection halva with the sesame press-cakes by simply adding honey to them. The peanut oil industry has been making Skippy and other brands of mainstream peanut butter out of the peanut press-cakes by adding cottonseed oil and other marginally edible oils to the peanut press-cakes.
Every agricultural district has agricultural byproducts that could be extracted economically for their non-edible fuel oils. The citrus juice industry could be extracting oil out of the seeds and skins of its residues. The apple juice industry could be extracting oil out of the apple seed residues. The avocado, apricot, peach and other pitted fruits, could also be extracted for their potential fuel oils. Some of these oils might be more valuable as health products, but those that are not can at least be used as a fuel source.
There are also native and wild sources of seed-oil in many regions, such as Grease Wood, Iron Wood, Palo Verde and Mesquite seeds in the Southwestern USA. Fuel could also be distilled from sawdust from the lumber industry of the Northwestern USA. There is even evidence that there are large amounts of fat available in the sewer stream. People are just not tapping these resources, so there are lots of sources of oil as a fuel that are simply going to waste and are often an environmental disposal problem that could be turned into an economic resource.
The SVO hobbyists have found recycled fryer fat is an acceptable fuel source, so smart, hard working people need only look around and keep experimenting with today's waste products to find tomorrow's fuel sources.
I hope this helps
Jeffrey S. Brooks