Dehydrating Mustard Extract

The goal of the project is to get an aqueous mustard extract solution at least 50% dry using a flash evaporator and shorten the overall drying time for the mustard extract. All while still being able to have a shelf-stable, shippable powder.

=Problem Definition=

Background
Mustard plants produce value oils and chemicals that can be processed into fuel and glucosinolates, respectively. Glucosinolates show promise of being used as biopesticides. Dr. Popova’s lab currently uses mustard meal after the oil has been pressed out to extract the glucosinolates. However the drying time takes three days for a 10-gallon batch, this is a bottleneck in the entire process.

Deliverables
Design an evaporation system that reduces the water content in the mustard seed extract by half.

Specifications

 * 1) Reduce water content in the mustard seed extract by half.
 * 2) Reduce the current drying time by half.
 * 3) No large drop in glucosinolates yield due to thermal degradation.
 * 4) No use of chemicals that could prevent the extract from being used in organic farming.
 * 5) The system can handle up to 10 gallons of mustard seed extract per day.

=Design Considerations=


 * This initial design was given to us by Dr. Popova, our client. This influenced our initial design.




 * Our initial design consideration. It was adjusted as more testing was being done.




 * We had planned to use this setup to test out a couple of pumps. However, we decided to use a pressure sprayer so we could better control the pressure that is being used.

=Final Design=

For our final design, we added copper piping and brass connectors and nozzle to our pressure sprayer. We also added an iron funnel at the bottom of our drum. We used 8020 for our frame. We placed to heat guns in a way that they would create a vortex inside the drum to help create a mist with the extract as it was being sprayed in.

After spraying the water into the drum three times, we got about 52% volume reduction, or 52% less water content that what we started with. Therefore, our requirement of 50% water reduction water met.

=Validation= We used tap water to conduct some tests with the pressure sprayer using a variety of pressures and nozzle settings.
 * For the first set of tests we used the plastic nozzle that came with the pressure sprayer and tested nozzles ranging from 10 psi to 95 psi. We saw a lower flow rate with a lower pressure setting. We were unable to reach 100 psi when we had 3 gallons of water in the pressure sprayer, which can safely handle 125 psi.

Once we assembled our copper piping and brass nozzle, we had to conduct more tests since our spraying system changed. We started with 85 psi and that gave us a flow rate of about 2.6 gallons per hour but not enough water evaporated. So, we lowered the pressure to 40 psi and that gave us a flow rate of 1.85 gallons an hour. Since less water would come out at any given time, this still allowed for the heat guns to keep the drum hot and evaporate some of the water.
 * We ran the water through a couple of times to test how many times the water would have to be run through to get 50% less water content. From out testing, after three rounds through our system we lose about 50% of our water. So, this goes to prove that at least 50% of the water content is removed and we can now go on to test our system with the mustard seed extract.
 * We tested our mustard seed extract and ran it through our system three times and got a 52% decrease in volume. We made a safe assumption that the 52% decrease in volume was water evaporation because our collection bucket was about 2 inches away from the outlet funnel and there was no visible water outside of the bucket. So, we reached out required 50% decrease in water content given that the extract is passed through our system three times.

=Recommendations=
 * 1) Look into adding insulation material to the outside of the drum to limit the amount of heat that leaves the system
 * 2) Add a humidity sensor, thermocouple, and an LED panel. This will allow to get quantifiable data, as not just assumptions.
 * 3) Consider narrowing the outlet funnel. As of right now, if the bucket is more than a couple of inches from the funnel or slightly offset, a lot of product is lost.
 * 4) Add support to the frame. The frame is unstable and has to be moved with extreme care and has to be tightened after every move, so finding a way to make it more stable or making a completely new frame will improve the stability.

=Team Members=

=Additional Documentation=

Project Schedule



Meeting Minutes



Presentations