Nasty nature of pyrolysis oil

As I posted a couple of days back, it is apparent that the exploitation of waste wood whose supply is maximized with better husbandry will supply feedstock that can then be converted through fast pyrolysis into something called Bio-oil. This conversion yields close to 70% by weight fluids, which is a pretty encouraging result.

The initial processing realistically includes harvesting in the form of wood chips, long term covered storage to permit a high level of air drying, and on time haulage to a processor. This is all within the capacity of the agriculturist. So far so good.

The second phase has two more preparation steps. The chips must be ground screened to the size of say coffee grounds and must also be heat dried to bring the moisture content to under 10%. This particularly true in the tropics were dry wood will absorb moisture from the atmosphere.

This material is then shoved through a reactor at a high speed and high temperature to produce the vaporized fluids and some char. It is then condensed to separate out the fluids and process gas.

I assume that we can scavenge the process gas and heat and use same to support the process.

The end result is a heavy cocktail of nasty fluids that is called bio oil, but chemically has little relationship to what we normally use. The good news though, is that this is a fluid that can now be compactly stored, handled, and transported. We also can have as much as we ever thought that we might need. It is actually practical, for a price, to produce a couple hundred millions of barrels per day of this stuff.

The actual energy content of this fluid is about forty percent of conventional fuel oil, which implies that we need at least twice as much to do the job. Extensive research over the past decades has found a way to burn this fluid in a static large engine. However, the nasty nature of this material has precluded anything more refined.

We have produced a fairly uniform and blendable feedstock. Can this feedstock be reformed into a hydrocarbon or alcohol product that we can actually use as a transportation fuel? Certainly there is a great deal of effort going toward that end. We are simply not there yet.

As I have posted, our salient unsolved problem today is the production of transportation fuel. Everything else is completely doable with the tools in hand. Been able to harvest waste wood and converting same into a liquid fuel would eliminate that problem in a carbon neutral way.

I do think that algae oil will present itself as a vastly superior fuel once its production is mastered. However, the benefits to the globe from active management of our woodlands are also compelling and should be economically sustainable if it is integrated into the fuel supply system. We very likely need to master both.

In the meanwhile, the price of oil and the Canadian dollar is on a tear as investors slowly wake up to the reality that the only place on Earth today that has any hope of making up some of the shortfall is in Alberta. And we are all now waiting for the other shoe to drop. That will be the first measured decline in oil deliveries and that information will already be months late.

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