Wednesday, January 27, 2010

Douglas Fir Needle Project

The basic concept is to harvest wind damaged Douglas Fir branches from local city parks. This is an environmentally conscious project. Harvesting downed branches helps with parks cleanup and reduces fire hazard. Our waste material then goes forward to be used as mulch. During our first distillation we had a somewhat disappointing yield, of only .04% The oil is quite lovely however. This problem is not insurmountable. First we brought the branches back to our distillery. We then chipped the branches in our small electric chipper. This proved to be very cumbersome and time consuming. The purpose for chipping the branches is to reduce the size of the material we are distilling, to enable us to get as much raw material into the still per batch. The more, the merrier! Our 100 gallon stainless steel steam distiller was then filled with chipped Douglas Fir branches. The steam was slowly brought into the retort at about 0.5 pounds pressure. After breakthrough (when distillate begins to flow from the condenser), we distilled for 1.5 hours. Upon opening the still we discovered that the plant material had been totally exhausted. Next time we distill Douglas Fir we will restrict the distillation time to one hour after breakthrough. Although the yield was somewhat disappointing, I am not discouraged. I feel that if we wait a few more weeks, when the Douglas Fir buds begins to open, there will be more oil present in the plant for distillation. Although we can certainly distill during the winter months, it looks like spring and fall will offer the best yields. Also, logistics must be worked out. The way we processed the material was time consuming, and in the long run not financially feasible. Next time, we will use our large chipper to expedite the process of reducing the particle size. A batch of branches can be chipped in the larger chipper in just a few minutes, as opposed to a few hours in our small electric chipper. Enough raw material needs to be brought to the distillery for at least two batches. As our distillery grows, we will be adding additional capacity. This project can serve as a model to others who wish to help out their local environment, while manufacturing a product free from harmful chemicals and sprays (providing of course that your local parks administrators don't spray their trees.) The Douglas Fir trees in Portland parks are not sprayed. This is a native species that does well here, and in most cases the trees are adults, and simply too large to spray. Along with making some beautiful oil, we als made lots of hydrosols. One of our staff member has taken the hydrosol home to be used in cleaning floors.

5 comments:

papalazarou said...

Fascinating stuff Robert - do you think the majority of the oil is in the xylum of the branch wood or in the needles? Might it be worth distilling them separately to find out? It might be possible to refine the procedure by stripping the needles somehow

Distiller said...

Hey Papa. I'm after the essential oil from the needles. The wood yields a resin, which is a whole other product.

Using small branches 1/2 inch or less, the "wood" doesn't contribute much if anything, and is mostly taking up space and being unproductive. Stripping the needles is OK on a small scale. I've done it, but when doing larger volumes of material, it's best to expedite things and sacrifice some percent yield for speed of production.

Siirenias said...

I noticed that you tried "resting" the incense cedar and not the fir. Any reason, or was that part just omitted?

As I recall, all needle trees have that waxy protection on the leaves. After all, conifers evolved the resin-filled leaf to protect their chlorophyll and other energy from non-specialized herbivores.

I'd love to run on and on about questions about resins, but I should really just man up and read the copy of The Compleat Distiller I got today, and then go ahead and shoot my mouth off.

Anonymous said...

What kind of distiller do you use ? I would like to make Doug fir oil, Please keep on doing what your doing!

Distiller said...

I use several different types of distillers. For the Douglas Fir Needle project I have been using a 100 gallon stainless steel steam distiller.

Are you located in the Northwest? Do you currently have distillation equipment?