FBM wrote:Over a year ago, I started using PVO (pure, unused, undiluted veg. oil) as a replacement for diesel in my Kia Retona. Actually, I sold my other car and bought the Kia just to do this experiment. The idea is that by using plant-source fuel instead of petroleum products, the CO2 pumped into the atmosphere by our vehicles will maintain at a fairly constant level. Plants will recapture the CO2 and the annual cycle would be fairly steady. Bringing up millions of years' worth of carbon in the form of oil in just a few decades is the main reason we have a problem with atmospheric pollution. The problem is, considering the number of vehicles in the world, deforestation to make room for veg. oil crops is a danger.
Rather than try to propose a solution for all the world's CO2 problems, I instead decided to just take control of my own emissions. (No, not those. From my car.) After researching the available online information on the topic, I decided to stop buying PVO and instead use only Waste Veg. Oil (WVO). I mentioned this to the group of professors I tutor, and one of them, a prof. in Applied Chemical Engineering, got excited about it. They arranged for me to buy the WVO from the campus cafeteria, which I filter and put straight into the tank. Then the Chemistry prof. got a group of seniors to do a series of experiments to measure viscosity, cloud point, pH, and a few other things at a range of temperatures and blends. They tested 100% diesel, 100% WVO, and blends of 25:75 (both ways) and 50:50.
The real issue is viscosity. Diesel viscosity is fairly constant until the temperature gets very, very cold. The viscosity of PVO and WVO increases relatively sharply as the temperature drops. Above a certain viscosity, it gums up the fuel filter and injectors and doesn't combust very cleanly in the chamber. This is exacerbated by the fact that my engine is a direct-injection type, and veg. oil works better in indirect-injection systems. I don't want to do a 2-tank conversion, nor convert the WVO into bio-diesel; I want to use 100% WVO as long as the weather allows, and gradually blend a minimum of petroleum fuel as the temperature drops in the winter. Just enough to keep the viscosity down to a useable level.
The experiments that the Chemistry students did gave me a fairly detailed guideline for the diesel:WVO blends that should work best at any given temperature. Those results have been published in Korean, but not in English yet.
This year, at my suggestion, the Chemistry students are repeating the experiments using kerosene instead of diesel. Why? Because the only real difference between diesel and kerosene is that kerosene has a lower inherent viscosity. This means that I could blend a smaller amount of petroleum-based fuel in with the WVO in order to achieve the required viscosity in cold weather. Less old CO2 pumped into the atmosphere. The results of those experiments should be ready this summer.
AND, kerosene is cheaper than diesel. I get the WVO for less than half the price of diesel, and kerosene prices are about 75% that of diesel. So far, I've saved...dunno...at least a thousand bucks on fuel expenses.
OK, that's one of the things I'm into right now. I don't really expect anyone else to be interested. Just thought I'd contribute something to the 'serious disscussions' pages.
Now, move along. Nothing to see here. Back to your regularly-scheduled programming.
Actually, I find this to be very interesting. I am not the least bit scientific minded, but, what I understand you to say is that essentially you are running your car on WVO as long as it's warm, and then, when the cold changes the viscosity of the WVO you adjust it with kerosene to keep things running smoothly. I am really curious to hear how that works out.
Why aren't we doing stuff like that here, in the US, where obtaining these items is pretty cheap and easy? All I hear about is WVO being useful only to produce bio-fuel. I assume the WVO is burning cleanly enough to not cause long term problems to your engine? Or, you don't know yet?