Water washing and titrated soap tests.

[nigelb]

Settling would be dead easy to do and could be done two ways ... with and without 7% prewash.

Without 7%
Finish the batch as normal, pump out to your wash tank, bubble overnight to demeth (no water) and simply leave for the soap to settle, testing for soap with a similar frequency as your first test.

With 7%
Process as normal but before draining glycerine, add 7% water and pump for 15 - 20 mins.  Settle and drain glycerine, then as above.

See how those go then maybe try an acid wash.

Those two tests are a no. Reasons are :

1. I'm not set up for demething and settling. The settling soap would block up my fuel oulet which is in the centre of the bottom of the tank.

2. Soap testing would be nothing short of inpractical due to only being able to take samples from the top of the fluid. This will be soap free very quickly if demethed effectively. Correct me if I'm wrong but soap settles from the top to the bottom. I'm not in a position to sample from part way down the tank.

Comments please.

[Tony]

GL seems to suggest this stratification of soap settling, but I've never personally seen it.  My bio has always been consistent in it's soapyness throughout (aside from the solid stuff at the bottom, or a layer of cream on top of that).

[K.H]

James may know? don't his tanks have take offs down the side for that reason?

I did suggest labelling them week 1, week 2 etc but i wouldn't want to start an argument 

[nigelb]

I've just been thinking about this problems while having a shower and came up with exactly the train of thought Keith. I was just about to post up and see that you already have.

[nigelb]

My bio has always been consistent in it's soapyness throughout (aside from the solid stuff at the bottom, or a layer of cream on top of that).

Is this backed up with soap tests, observations or 50/50 tests Tony. Trying to get my head round it.

[Soft top]

I made a batch of bio today and thought that I would play with my new soap testing kit when doing the water wash.
This is the results.
I first did a 2 stage no tit and got a clear pass. Then did wbd and then 7% pre wash. After I drained the glyc/water I took a sample of the bio and tested for soap.
As expected it was high.....2400ppm.
After 1st wash it was....304ppm
After 2nd wash it was....96ppm
After 3rd wash it was.....54.4ppm
Total time spent washing.....3 hours
By the time I need to use it (next week) more soap should settle out.

[1958steveflying]

I made a batch of bio today and thought that I would play with my new soap testing kit when doing the water wash.
This is the results.
I first did a 2 stage no tit and got a clear pass. Then did wbd and then 7% pre wash. After I drained the glyc/water I took a sample of the bio and tested for soap.
As expected it was high.....2400ppm.
After 1st wash it was....304ppm
After 2nd wash it was....96ppm
After 3rd wash it was.....54.4ppm
Total time spent washing.....3 hours
By the time I need to use it (next week) more soap should settle out.

Excellent result's.

[Soft top]

I made a batch of bio today and thought that I would play with my new soap testing kit when doing the water wash.
This is the results.
I first did a 2 stage no tit and got a clear pass. Then did wbd and then 7% pre wash. After I drained the glyc/water I took a sample of the bio and tested for soap.
As expected it was high.....2400ppm.
After 1st wash it was....304ppm
After 2nd wash it was....96ppm
After 3rd wash it was.....54.4ppm
Total time spent washing.....3 hours
By the time I need to use it (next week) more soap should settle out.

Excellent result's.

Thanks.
I have used this method for 2 winters now but never had a clue how much soap was in my bio so thought it was about time to find out.

[1958steveflying]

I made a batch of bio today and thought that I would play with my new soap testing kit when doing the water wash.
This is the results.
I first did a 2 stage no tit and got a clear pass. Then did wbd and then 7% pre wash. After I drained the glyc/water I took a sample of the bio and tested for soap.
As expected it was high.....2400ppm.
After 1st wash it was....304ppm
After 2nd wash it was....96ppm
After 3rd wash it was.....54.4ppm
Total time spent washing.....3 hours
By the time I need to use it (next week) more soap should settle out.

Excellent result's.

Thanks.
I have used this method for 2 winters now but never had a clue how much soap was in my bio so thought it was about time to find out.

What is your wash procedure and what drying process do you use ?

[Soft top]

I made a batch of bio today and thought that I would play with my new soap testing kit when doing the water wash.
This is the results.
I first did a 2 stage no tit and got a clear pass. Then did wbd and then 7% pre wash. After I drained the glyc/water I took a sample of the bio and tested for soap.
As expected it was high.....2400ppm.
After 1st wash it was....304ppm
After 2nd wash it was....96ppm
After 3rd wash it was.....54.4ppm
Total time spent washing.....3 hours
By the time I need to use it (next week) more soap should settle out.

Excellent result's.

Thanks.
I have used this method for 2 winters now but never had a clue how much soap was in my bio so thought it was about time to find out.

What is your wash procedure and what drying process do you use ?

When I start washing the bio is still hot, about 75 degrees, after wbd.
 I mist spray 20 to 25 litres of cold water into top of processor at a rate of 2 litres a minute. I then leave it to settle for 40 minutes and then drain. Takes 1 hour to fill, settle and drain.
I then do that again twice more.
By the time I do the 3rd and last wash the temp of the oil is down to about 50 degrees.
When draining I stop the moment I see the creamy stuff between the water and the bio coming out. I dont wait until I see bio. I found I lose bio if I do that.
The only time I got an emulsion was when I turned the pump on when water was in the processor so I never turn it on now when washing.
I dry my bio by pumping into an open top settling tank via a spray bar. When the tank is full I then turn heater on and get the temp to about 60 degrees while circulating through the spray bar with a fan blowing across the top. I have had clear bio after an hour but sometimes it takes longer.

[1958steveflying]

I made a batch of bio today and thought that I would play with my new soap testing kit when doing the water wash.
This is the results.
I first did a 2 stage no tit and got a clear pass. Then did wbd and then 7% pre wash. After I drained the glyc/water I took a sample of the bio and tested for soap.
As expected it was high.....2400ppm.
After 1st wash it was....304ppm
After 2nd wash it was....96ppm
After 3rd wash it was.....54.4ppm
Total time spent washing.....3 hours
By the time I need to use it (next week) more soap should settle out.

Excellent result's.

Thanks.
I have used this method for 2 winters now but never had a clue how much soap was in my bio so thought it was about time to find out.

What is your wash procedure and what drying process do you use ?

When I start washing the bio is still hot, about 75 degrees, after wbd.
 I mist spray 20 to 25 litres of cold water into top of processor at a rate of 2 litres a minute. I then leave it to settle for 40 minutes and then drain. Takes 1 hour to fill, settle and drain.
I then do that again twice more.
By the time I do the 3rd and last wash the temp of the oil is down to about 50 degrees.
When draining I stop the moment I see the creamy stuff between the water and the bio coming out. I dont wait until I see bio. I found I lose bio if I do that.
The only time I got an emulsion was when I turned the pump on when water was in the processor so I never turn it on now when washing.
I dry my bio by pumping into an open top settling tank via a spray bar. When the tank is full I then turn heater on and get the temp to about 60 degrees while circulating through the spray bar with a fan blowing across the top. I have had clear bio after an hour but sometimes it takes longer.

Clearly a good quick process and nice low soap PPM's for mist washing.   

[nigelb]

I made a batch of bio today and thought that I would play with my new soap testing kit when doing the water wash.
This is the results.
I first did a 2 stage no tit and got a clear pass. Then did wbd and then 7% pre wash. After I drained the glyc/water I took a sample of the bio and tested for soap.
As expected it was high.....2400ppm.
After 1st wash it was....304ppm
After 2nd wash it was....96ppm
After 3rd wash it was.....54.4ppm
Total time spent washing.....3 hours
By the time I need to use it (next week) more soap should settle out.

Fantastic results there Soft top.

[Jamesrl]

GL seems to suggest this stratification of soap settling, but I've never personally seen it.  My bio has always been consistent in it's soapyness throughout (aside from the solid stuff at the bottom, or a layer of cream on top of that).

That's precisely the reason for the take off points at different heights on my settling tanks.

Though only tested with 50/50 tests, I can draw of the top section,25ltr after a clear water test but the next valve down will return a fail.

Stratification of soap IS true as the Master says. 

[Tony]

GL seems to suggest this stratification of soap settling, but I've never personally seen it.  My bio has always been consistent in it's soapyness throughout (aside from the solid stuff at the bottom, or a layer of cream on top of that).

That's precisely the reason for the take off points at different heights on my settling tanks.

Though only tested with 50/50 tests, I can draw of the top section,25ltr after a clear water test but the next valve down will return a fail.

Stratification of soap IS true as the Master says.

What sort of settle time is that after?

I ask because even with a warm reaction sample settling for the 3/27 test, while the glycerol sinks there is clear stratification until settling is complete a couple of minutes later.

Surely the same should apply to cold bio soap settling but over a much longer period of time?

[nigelb]

Following good scientific testing practice I've done a follow up set of titrated soap tests on the batch I made this weekend. I made attempts at testing the biodiesel prior to the 7% post reaction wash which I'll publish in a seperate thread.

The biodiesel was, again, made with ASM and I used the two stage no titration method. The final quality test (45/5) was crystal clear, no dropout or haziness. Each wash used 10lts of water.

Test 1
Raw biodiesel having been treated with a 7% post reaction water wash.
2.8ml of 0.01N HCl = 851.2ppm

Test 2 (after wash1)
After 6hrs of gentle bubbling (wash 1)
1.5ml of 0.01N HCl = 456ppm

Test 3 (after wash 2)
After 10hrs of gentle washing (wash 2)
0.55ml of 0.01N HCl = 167.2ppm
 
Test 4 (after wash 3)
After and overnight wash (wash 3)
0.07ml of 0.01N HCl = 21.28ppm

Because of the low level of soaps in wash 3 I decided not to bother with my usual hot pump wash. It's always nice to reduce the number of steps in the process.

Nige