Vegetable Oil SVO WVO waste cooking oil as biofuel

[SunWizard]

Now that I have bought and compared most of the water testing methods listed in post#1, ASTM D2709, Sandy Brae, and HPT, the water test I like best is one not listed: capacitive % saturated meter
Its easier and faster than any of them.

500ppm is considered the lower limit of the HPT sensitivity.

From comparing HPT with sandy brae, the lower limit depends on FFA level. On my 4.5% FFA sample, 1500 PPM passed the HPT with no bubbles. See this thread for more details: WVO science project, FFA, standards and water testing

[John Galt]

My favorite is the fast and easy vapor test; how did it compare?

[SunWizard]

I got bad results with the vapor test, all my calibrated samples including my 1500 ppm sample had no vapor ring. I even tried chilling the piece of glass that I used in the refrig. to 40F and it still showed no vapor. The only times I got a vapor result is with my >5000 ppm samples which is far too much water. And even with those, the results varied widely, probably depending on how hot the glass piece got during the 1 to 2 minutes its microwaving.

I always get well below 0 suspended water, which is 0 bubbles on a HPT, and 0 ring of vapor, and want to know how far below that 100% saturated point I am.

For biodiesel, the Karl Fischer test used is ASTM D6304, which is coulometric and better for WVO as well. Its supposed to be much better than the E203 you mention in post#1, and better for <500 ppm, they even say this on the ASTM page you linked.

[John Galt]

That's good to know. So the vapor test isn't any better than the HPT. Looks like I'm going to have to find a source for the FFA test strips and capacitive % saturated meter parts up here in Canukland.

[SunWizard]

Looks like I'm going to have to find a source for the FFA test strips and capacitive % saturated meter parts up here in Canukland.

Digikey for the sensor ships to canada, and capacitance meters are common and should be easy to find. Although its hard to get the specs on it to be sure its a 0.5% accuracy model.

[zoochy]

That's good to know. So the vapor test isn't any better than the HPT. Looks like I'm going to have to find a source for the FFA test strips and capacitive % saturated meter parts up here in Canukland.

@John: Did you manage to find a source for FFA test strips that ship to Canadian addresses? If so, could you please share your source as I have had no luck.

[John Galt]

no I didn't

[John Galt]

Of all the water test methods the carbide manometer is the least expensive and most accurate for the cost.
http://make-biodiesel.org/Quality-Testi ... rbide.html

Simple U-Tube manometer: meter stick, 5mm tube, binder clips



Simple U-Tube manometer: 'canning jar' cap for carbide test, 500ppm & 1000 ppm calibration marks
Canning jar cap with screw ring fits a variety of jars for the carbide reaction chamber




Tube mortar for crushing carbide: 3/4 pipe 6", 2 end caps, 3" piece of 1/2" rod, 'tea' sieve, funnel



Finely pulverized carbide gives the best test results. Particles caught by the sieve are returned to the mortar for powdering. Powdered carbide that passes the sieve is stored in an airtight container for tests.



For calibration I found it easy to dry 2 liters of BD, then add 1ml to one liter for 1000ppm, and finally mix 300ml of each to make the 500ppm sample. The 1000ppm tested at 31.0 to 31.4 cm and the 500ppm at 15.4 to 15.8 cm, for a calibration constant of 32ppm/cm.

The manometer tube is attached to the meter stick with 1" binder clips,

masking tape was placed on the meter stick and the calibration levels marked on the tape.

The manometer assembly hangs from a hook and the 500 ppm calibration marks are a convenient go/no-go reference. A short piece of 6mm OD tube is sealed into the jar lid so the manometer is easily connected/disconnected.