abstract
-
University of Idaho plant scientists have developed rapeseed, canola, and yellow mustard varieties that have the potential to significantly reduce the cost of the oil used in biodiesel production. This project is for purposes of producing quantities of biodiesel from these locally grown varieties to test in laboratory engines and in both a 1999 Dodge 2500 diesel powered on-road pickup truck and a 2001 Volkswagen TDI Beetle. The Beetle will be used for demonstration events and on-road testing to verify the suitability of biodiesel for urban transportation use. As part of the test protocol, fuel characterization tests will be conducted to verify that the biodiesel produced meets the interim ASTM standard for biodiesel.
The University of Idaho campus has a central core with parking facilities around the peripheral. Two years ago a Campus Commons facility was created in the center core of the campus. If faculty, staff, and students are to make adequate use of the parking facilities a campus transportation system is needed. Many University and non-university events are held at the Commons. Access to this facility except by walking is limited. Especially the elderly and handicapped have difficulty on the campus. A campus transportation system is needed. During this last year we cooperated with campus transportation to provide a blend of biodiesel and diesel to power the Vandal Trolley.
The trolley was a popular vehicle for campus events and provided an excellent platform for testing locally grown and produced biodiesel in typical bus service. We are also interested in developing a tram concept for the campus. During the past year, the possibility of a tram was investigated and found to be cost prohibitive with the present budget. Developing a simple tram from existing equipment was found to be difficult because of safety and liability issues. Ultimately, if we are to be successful at solving the campus transportation problem, a number of people movers would be needed. Therefore, additional alternatives to the Vandal Trolley will be considered.
Emissions data is a critical aspect of testing with alternative fuels such as the yellow mustard biodiesel tests proposed in this project. University of Idaho personnel have conducted four weeks of emissions testing on the transient chassis dynamometer at the Los Angeles Metropolitan Test Authority emissions test facility. During this past year, mode tests using the UI chassis dynamometer test facility were conducted. It was found that none of the data from the existing five-gas analyzer appeared reliable except for perhaps the NOx data. Since NOx is the most critical emission issue with diesel engines, we are proposing to continue with additional emissions studies replicating an earlier study at LA-MTA where we found a correlation between vegetable oil iodine number and NOx. If this study could be repeated and data compared with the earlier tests to determine if a suitable screening procedure could be developed. Conducting emissions tests locally would allow for more varieties feedstock to be evaluated and would save considerable time and money. The exact vehicles used for the earlier tests at LA MTA (1994 Dodge/Cummins owned by the UI and 1995 Dodge/Cummins operated by Yellowstone National Park), the original second-by-second data, and original fuel types (this includes rapeseed ethyl and methyl esters, HySEE and Phillips 66 low sulfur diesel reference fuel), are still available, thus enhancing the chance for success of this activity.Biodiesel, esterified vegetable oil, is gaining favor in many applications. The fuel equipment manufacturers and engine manufacturers recommend using biodiesel in blends of 5 percent or less. There is data from the U of I and elsewhere that suggests that in low level blends, non-esterified vegetable oils could be used. One current study in Alaska with fish oil is using non-esterified oils at the 50 percent blend level and evidently with good success. A study in Ireland, demonstrated that non-esterified, degummed oils could be used up to the 20 percent blend level. The inherent problem with non-esserified oils is the remaining glycerol which is sugar and which can cause polymerization in the combustion chamber. However, there is evidence that this problem may be avoidable when the blend level is low. The second issue is that one of the reasons for using biodiesel is as a lubricity enhancer. We propose a series of lubricity tests with biodiesel and a range of feedstocks from the U of I breeding program to determine if non-esterified oils are equivalent to esterified oils as lubricity enhancers for low sulphur diesel.
Two simple tests for evaluating combustion chamber deposits have been used in our program. The first is an injector coking test which uses the injector, a removable element of the combustion chamber to evaluate coking propensity. The second, which has been used less frequently, is to use a 2-cycle engine where the biodiesel or vegetable oil is blended with gasoline and used as the two-cycle lubricant. This test accelerates the tendency for polymerization to occur. Initially, this test will be conducted with fish oil from the Alaska non-eserified oil studies to determine if the two-cycle test would predict the advantage of fish oil over other oils. Secondly, the two-cycle test will be used with a range of feedstocks from the breeding program to determine if some fatty acid compositions are superior as a non-esterified oil.
The third part of the tests with low-level non-esterified oils is to develop long term tests with standard diesel engines to determine potential operational problems.We propose identifying at least two diesel engines, one in a stationary platform to be operated in the durability dynamometer facility and other in an on-road configuration to be operated as a vehicle in normal use.