Concentrat technique?

I am about to build a prototype for an extractor that I think would be legal in California for extracting "the good stuff". I wrote a project proposal on the subject. I know it is long, but I would greatly appreciate any comments. The proposal dissertation follows.

California Legal Extractor

California law prohibits extracting the active ingredients by use of any solvent. Water, steam, and fats are not currently considered solvents but that could change. This method avoids that problem.

The method is called destructive distillation. The material is heated, sometimes to the point of ash, without burning, most often in a non-oxidizing atmosphere. The fumes thus created are drawn through a fractionating cooling tower, drawing off condensate at several specific temperature ranges. This is called fractionating.

I must point out at this point that most will not need or want to bring the temperature to the point of ash (above 200 C may be counter productive) and can use a simple distillation apparatus. Any vaporizer that can be made into a closed system and any condenser will do. You just have to collect each component, shut down and change the collection bottle, then reset for another temperature and start again. The fractionating tower does it all at once.

The heating chamber can be quite variable as all it must do is insure the charge gets completely heated. It can work by convection as an alcohol still and petroleum stills do, but the most efficient system would include a compressor or fan to circulate the non-oxidizing atmosphere up or down the fractionating column depending on design.

There are several ways to design a fractionating column but the desired result is to have the column cool the vapors from the carrier gas, with one end being cooler then the other and several â??tapsâ? of condensate down the length of the tower. By controlling the amount of cooling over the length of the tower and the placement of taps you can achieve separation of condensate into several fractions with differing BPs.

A column consists of a tube divided into chambers with condensate collection points. The vapors are cooled either by plates, baffles, or â??packingâ? which is in turn cooled by water jackets on the whole column or individual sections, or in the case of plates the plates themselves. The purpose is to create the largest surface at the specific BP temperature you wish to collect in each of the chambers. To increase this surface area many use â??packingâ? consisting of metal wool (steel wool works but rusts so I prefer brass wool) or glass, ceramic, or metal beads.

The metal wool has the advantage of the largest surface area and both the advantage and disadvantage of fast heat conduction. Packing of the other materials have thermal mass and heat and cool more slowly, which means they can hold a temperature better, but have a smaller surface area to volume ratio.

My personal preference for a fractionating unit is a little different then most. It consists of a copper or brass tube (no rust) that is pinched or baffled to create chambers. The tube is tilted slightly from the horizontal with the higher end being the hot end. There is a hole on the lower, bottom end of each chamber with a fitting soldered or brazed to it for a collection chamber (glass preferred). Each chamber is then wrapped with smaller copper tubing soldered or brazed to it as a cooling jacket. A single water jacket is much simpler and can be used. This is my preference for better control. In fact I would like automatic control of cooling water flow at each chamber to achieve the most consistent result.

In practice you adjust the carrier gas flow and cooling water flow to each chamber to get condensate in the correct temperature range in each collection point. This can be improved with accurate control of heating temperatures and cooling jacket temperatures. I lean toward thermocouples in the gas flow entering and leaving the tower and at the collection point in each chamber. The heater is adjusted to control the inlet temp. The flow through each water jacket is controlled to achieve the proper condensate in each collection, and in turn the exit temperature. Exit temperature variables are you want it to be low enough to assure all constituents you want are collected and high enough to save on reheating because this is a closed system. You do not care about reflux rate, though it increases recovery, because your carrier is an inert gas.

Because of the different BPs of constituents you now have the ability to adjust the final product by blending the condensates to your particular goal.

You can then make hash, tinctures, and edibles with medicine adjusted to particular prescriptions for pain, appetite, anxiety, and other medical uses and honestly say that no solvent was used in the extraction.

The final product has been heated and can be used in cold preparations. The advantage over butter or oil extraction is in blending and control. That is because testing the condensate is easy. Testing oily concentrates is difficult.

I am about to build a prototype using my vaporizer. I will need a sealed pump or fan for the nitrogen atmosphere I plan to use and plan to use a vaporizer bag on the inlet side of the pump as an expansion chamber. I will probably use thermometer ports on the initial build and manual water valves then convert to thermocouples and electronic cooling flow control.

Process time should be measured in minutes not the days or weeks needed for solvent extraction and the system can be designed to operate at a partial vacuum to lower boiling temperatures if needed.

What do you think??