quote:

Originally posted by Eurocab:
Of course, PVC columns are allegedly taboo for filtering BD with resin. I have heard that there is some kind of chemical reaction that takes place and causes fissures in the PVC.

I have been using two small PVC columns for about six months with no problems. I guess only time will tell.

Heres a few.

I've been waiting for those bad boys to come out...

How long did you run it in them though? If I remember right they held on for quite a while but eventually finally split...

-Graydon

The first one is from another forum member it happened over nite.

The second one lasted about 2 months.

There was one other that lasted 2 weeks.

Chads,

Which type resin were they using in the columns that split? I am still using your macroporous with no problems. Could it be the expansion of the amberlite or purolite that is contributing to the problem? Or could it be the diameter of the pipe used that is causing the problem?

Like I said going on about 6 months with no problems in mine.

I think the top one was purolite in a 3 or 4 in pvc tube.

The bottom was macro in a 6" pvc tube.

I think with the small dia pipe there's not enough resin volume in it for the chemical reaction that's happening in the larger sizes.

Hi Chad,

I always thought it was the hoop stresses from compaction that split them out. Hoop stresses can build rapidly on the larger tubes just based on the geometry. I've seen a number of the smaller tubes that lasted much longer. The key is to make them small enough that you can flip them over and resettle the beads every so often.

All that said, I still prefer steel for more permanent applications.

quote:

Originally posted by RickDaTech:
Hi Chad,

I always thought it was the hoop stresses from compaction that split them out. Hoop stresses can build rapidly on the larger tubes just based on the geometry. I've seen a number of the smaller tubes that lasted much longer. The key is to make them small enough that you can flip them over and resettle the beads every so often.

All that said, I still prefer steel for more permanent applications.

-I'm not sure that it compacted inside of 2 weeks with very little fuel run through it.
-But fuel did sit in the columns while not in use.

Anyways like you said steel is the best way to go.

I got tired of even using pcv for testing so I built these little testing units 3"x 36" up & down flow.
Thermax has a few more products that we have to test out before we release them, so no more worries.

Just picked them up from the powder coater today.

Chad, those look cool!
Almost like little rockets!

Cute little suckers...

I like em!
-Graydon

Thanks.
I thought they did too when I first built them.

Chad thanks for the pics. You saved me from building the pvc columns. I have a 10ft length of 4.5" 316 stainless i'll definatly be using that.

So the 2009 National Biodiesel Conference is over and in the history books - not a huge turn out this year apparently maybe 1/3 of past participation...

However the highlights were the Biodiesel Sustainability Summit just prior to the NBB Conf., The San Francisco premier of the Josh Tickell's biodiesel documentary "FUEL" (spectacular!!!)

Arbor Biofuels Company plans to sponser this film and bring it to Ann Arbor, Michigan later this Spring - we should get as many people there as possible - its very personal and inspirational...

We had our miniature lead lag system (little rockets) there and thanks to Raften, about 10 gallons of unwashed biodiesel to run a few demonstrations on Sunday.

The cool thing was one of the leading FTIR analysis companies Cognis QTA’s performed about $500 worth of biodiesel purification analysis for FREE on the demonstration samples.

There unit in 2 minutes can accurately test for 15 of the ASTM test.

Anyway the test results were perfect and I will post photo copies later. The technician working the QTA booth initially tested the raw crude biodiesel and his first comment was; "oh this biodiesel isn't going to pass spec." He said that because the total glycerin count was off scale high for their tester and the only parameters of the ASTM test to pass were Ester conversion, Acid Number or Acid Value and viscosity.

However the post lead lag system containing Thermax Tulsion T45 BD resins passed every test except for the Acid Value which is due to the overnight soak time of the initial biodiesel...

Chad and I use to recommend soaking the biodiesel overnight since that is the practice used to initiall expand the gel type resins however with the macroporous resin we simply suggest backfilling to remove air and then start pumping. Not even worrying about the gel resin in the lag bed since initially it isn't doing the work anyway and it will expand over time...

GCG