A BP A+ For Energy Project
Here is the PDF version of the final report that was submitted to BP. This document summarizes a year long effort to build and operate a small biodiesel production facility, as well as educate our student body on the details of biodiesel. The picture below shows one of the tractors we are running off of biodiesel and the magnetic sign designed by Brian Lamore to advertise that fact.
Earlier in the year, I gave a lecture to the Chemistry and Environmental Science classes on the background, uses, production overview, and hurdles associated with biodiesel. The students were given a preassessment and then following the lab were given a post-assessment. Files are linked below.
I must preface this post with the comment that I have only had one year of experience with biodiesel and am still very much a newbie. However, given the stated goals of our BP A+ for Energy grant, I felt it important to include a post on sustainability and biodiesel. There are two items I could discuss under this heading: (1) the sustainability of biodiesel as a viable alternative liquid energy source, and (2) sustainable practices when making biodiesel. I’m going to discuss our efforts at the school to incorporate the later.
Most of what I have learned about the environmental impact of making biodiesel (and about biodiesel in general) has come from William Kemp’s great book Biodiesel: Basics and Beyond. I will admit that I was one of the many naive tinkerers who was caught up in the rhetoric of homebrew biodiesel. Every website I visited mostly reinforced the idea that making biodiesel was a simple procedure that nearly anyone could accomplish. If you delve deeper into various biodiesel forums, you can obtain a little better idea of potential issues and complications that aren’t advertised by those trying to sell you overpriced processor kits. However, despite the prevalence of hyped advertising/rhetoric, the biodiesel community is largely comprised (from my experience) with a lot of helpful people that are trying to spread their knowledge and the benefits of biodiesel.
Where there are shortcuts, there will be people who take them, and biodiesel production is no exception. Kemp addresses these shortcuts as “Myth Buster” sections in his book and does a thorough and convincing job of debunking these shortcuts. Biodiesel has two inputs that are harmful to humans and the environment: methanol and sodium or potassium hydroxide. I won’t go into much detail here except to say that ensuring that these harmful inputs don’t become harmful outputs somewhat complicates the biodiesel process. Any unreacted methanol has to be recovered and any wash water that has been contaminated with the NaOH or KOH base used in the reaction has to be neutralized with an acid prior to disposal. While there are fairly simple methods for accomplishing these tasks, most biodiesel homebrewers I’ve encountered don’t include these steps.
In stressing the harmful nature of some of the chemical inputs to the students, they were naturally curious about any harmful byproducts created in the process. Wonderfully, biodiesel and its byproducts are amazingly benign as long as you recover any excess methanol and neutralize your wash water. We were sure to include a discussion of these issues with the students involved in the project, and as our processing continues over the years we will continue to emphasize the importance of environmental sustainability over simplification of the process. The specifics of how we employed methanol recovery and wash water neutralization in our process will be included in future video posts.
Towards the end of the semester, the 10th grade Chemistry class did a 3-day biodiesel lab. On the first day, the students titrated a batch of waste-vegtable-oil (WVO) in order to determine the amount of KOH catalyst to add to the methanol. On the second day, the students added heated WVO to 2-liter soda bottles that already contained the correct amount of methoxide. The students shook the bottles to start the biodiesel reaction. The third day was spent draining the glycerin byproduct from the bottom of the bottles and then performing multiple water washes. Relevant lab sheets and links are provided below along with pictures from the lab.
After a lot of hard work and what seems like a million trips to Lowe’s, the biodiesel processing shed is up and running. We’ve made two successful batches of biodiesel (20 gal and 45 gal) that have been running in our three school tractors without any problems. The fuel tested well on the two homebrewers tests we have done: phLip test, and the 3/27 test. Some photos of the shed are posted below. Explanatory videos of the process are soon to come (though my flip camera is missbehaving so we might have to reshoot these videos next year).
Earlier in the school year we drove around Highlands and Baytown, Texas in search of waste-vegetable-oil (WVO) that we could convert into biodiesel. Some of the biodiesel leadership group students came along to help convince local restaurants to give us their WVO. Unfortunately, we figured out quite quickly that even in small-town Texas, every restaurant is already in a contract with a large waste-oil rendering company that pays them around $.50/gal for their WVO. We were able to obtain a few samples of oil though and perform a few titrations (see picture below). Interestingly enough, none of the oil we obtained was very good so it was probably best that they didn’t offer us any.
First Titration
Because we had a lot of work ahead of us getting the biodiesel processing plant setup and running, we decided not to pursue getting free WVO any further. Instead, we found a local biodiesel brewer who provided us with unfiltered WVO at $.40/gal. He obtained his oil from local Italian and Asian restaurants as well as community fish fries and had more oil than he could use. It seems that in today’s market where WVO is a commodity that is traded and indeed valuable enough that theives are beginning to steal it from restaurant collection bins, the best source of free or cheap WVO is from these types of temporary fryers (like community/church fish fries, little league concession stands, etc.). Next school year, we will pursue more local sources of WVO and do some better local canvassing/advertising.
We completed building a storage shed to house the biodiesel processing unit back in January. The process involved significant student assistance and was a great way for students to learn basic construction. The shed was framed inside of a section of an open shop garage and the walls were both insulated and sheetrocked. In the future students will paint the outside with a biodiesel related mural. See future posts for updated pictures of the shed.
Biodiesel group students standing in the newly framed biodiesel shed.