OK Some Updates.

The Beta testing didn't really follow the strict scientific rules, and not everyone has reported in yet. But I do have enough feedback so far to have a high level of confidence in what I'm about to say.

Bad News First.

There was a lot of concern about the eductor being plastic. Questions about life expectancy and such.

There was some concern about whether or not the HF pumps could take the increased pressure long term without blowing out the seals.

Good News!

They work better than expected. The guys that were worried about pressures drilled out the nozzles for lower pressures and still had impressive gains. For our small processors (under 100 gallons) the slightest in tank mixing makes dramatic improvements in quality OR allow for reductions in methanol OR reductions in total mixing time OR some combination of the above.

For the Appleseed DIY guy, I'd recommend something like this:




The change I would make to this drawing is to eliminate the bell reducer by replacing the 1/2" pipe with schedule 80 pipe and tapping the inside of one end with 3/8" threads. Then you can screw the bushing directly into the end and insert the whole thing through a 3/4" port on top. You may even be able to use a 1/4" nipple as a nozzle and reduce the pressure on the pump seals.

Nice picture.

So here comes the dumb question.

So in the above diagram are you saying that just by changing the output of the appleseed to a higher pressure output below the fluid level we can realize an increase in mixing without using an eductor?

This is still an eductor of sorts. It just does not have the diffuser on it. The diffuser takes it from a 3X flow to a 5X flow. Not all eductors have the diffusers on them.

Like I was saying, even just a little bit of mixing is good enough for our small processors. You should see significant gains with just this pipe eductor.

I realize I am late to this thread but I have been researching eductors for a while. These folks: http://www.1877eductors.com/
Have some sizing charts that are pretty interesting. I did some math based on pump curves for the NT pump, and it will draw 25" of vacuum with a 1" MLE eductor. I sent them an email asking for a quote but never got a response (also asked for tank mixers. My request follows:

quote:

I am researching eductors for use in a biodiesel reactor project. Can you provide a quote for a model MLE, sized at 1" diameter, in carbon steel? I am also interested in your tank mixing product, but am not set on the size of the opening in the tank. Can you provide quotes on sizes 3/8, 3/4, and 1 1/2" TLA tank mixers in carbon steel. For information, I intend to use these with a side-channel pump with a max head of 110' and a max flow of 12 gpm.

Perhaps if they got the request from an actual retailer they may be more responsive?

R2.0

Oh, yeah - another eductor:

http://www.pythonproducts.com/repparts.html

The "Faucet Pump", 13B, is an eductor made of thermoplastic. It draws a good vacuum (I have one for my aquarium) and is cheap - $5.00 at Petsmart. It may not last very long, but at that price one can buy a bunch.

One other advantage of the eductor that I forgot to point out. The eductor improves mixing to the point that the methoxide can be pumped in as fast as you can go. It puts an end to the "take 30 minutes to introduce the methanol" step of the Appleseed instructions.

I've always thought the toughest part of operating an Appleseed was getting the methoxide to go in at the right flow rate. An eductor lets you just open up the methoxide valve and close off the tank isolation valve and pump it into the tank without any adverse effects on quality.

quote:

Originally posted by R2.0:
Oh, yeah - another eductor:

http://www.pythonproducts.com/repparts.html

The "Faucet Pump", 13B, is an eductor made of thermoplastic. It draws a good vacuum (I have one for my aquarium) and is cheap - $5.00 at Petsmart. It may not last very long, but at that price one can buy a bunch.

That's actually a venturi not an eductor. They work on a similar principal, but are used in different applications. It would not work as an eductor. sorry.

quote:

Originally posted by R2.0:
I realize I am late to this thread but I have been researching eductors for a while. These folks: http://www.1877eductors.com/
Have some sizing charts that are pretty interesting. I did some math based on pump curves for the NT pump, and it will draw 25" of vacuum with a 1" MLE eductor. I sent them an email asking for a quote but never got a response (also asked for tank mixers. My request follows:

quote:

I am researching eductors for use in a biodiesel reactor project. Can you provide a quote for a model MLE, sized at 1" diameter, in carbon steel? I am also interested in your tank mixing product, but am not set on the size of the opening in the tank. Can you provide quotes on sizes 3/8, 3/4, and 1 1/2" TLA tank mixers in carbon steel. For information, I intend to use these with a side-channel pump with a max head of 110' and a max flow of 12 gpm.

Perhaps if they got the request from an actual retailer they may be more responsive?

R2.0

There are quite a few companies that make and sell eductors. There choices are plentiful for drum and other processors. The choices for an appleseed are limited due to the 1" maximum dia requirement that is needed to install them inside a water heater.

I've dealt with a number of eductor companies and found that most are not as responsive as I would have hoped.

quote:

Originally posted by RickDaTech:

For the Appleseed DIY guy, I'd recommend something like this:

The change I would make to this drawing is to eliminate the bell reducer by replacing the 1/2" pipe with schedule 80 pipe and tapping the inside of one end with 3/8" threads. Then you can screw the bushing directly into the end and insert the whole thing through a 3/4" port on top. You may even be able to use a 1/4" nipple as a nozzle and reduce the pressure on the pump seals.

For a 1" pipe thread, like a water heater element thread, would one just up the diameter of each section in drawing? Or is the 1/8" end piece properly sized for a HF clear water pump?

Rick also mentioned you could increase the size to 1/4" for the nozzle. So depending on your pump you may need to do a little experimenting.

quote:

Originally posted by RickDaTech:

quote:

Originally posted by R2.0:
Oh, yeah - another eductor:

http://www.pythonproducts.com/repparts.html

The "Faucet Pump", 13B, is an eductor made of thermoplastic. It draws a good vacuum (I have one for my aquarium) and is cheap - $5.00 at Petsmart. It may not last very long, but at that price one can buy a bunch.

That's actually a venturi not an eductor. They work on a similar principal, but are used in different applications. It would not work as an eductor. sorry.

No, it's an eductor - I have disassembled mine.

I think we may be using the same terminology for different things. You are looking for a tank eductor, to mix the contents of the tank better, i think. I have been looking for an in-line eductor to replace the venturi section in the GL processor.

been using these with great results.
http://www.biodieselpictures.com/viewtopic.php?p=1094#1094

Shawn,

Yep, Those do a great job! They would work great in anything with an access hole big enough to get them inside the mixing tank. I've found a whole bunch of different eductors that will fit in through a 2" bung. What's hard to find is one you can get inside an Appleseed.

yeah i wanted some better mixing so i was forced to make a drum processor when my appleseed was taking a little too long. wish i would have one or two of those little guys a while ago

Now if I were doing an Appleturnover, I'd weld a 2" weld coupling into the top (was bottom). Then use one of these bushings so I could mount a full sized eductor inside the tank.

Rick - Do you have plans to continue to report results as your other testers provide infomation?

Tks.

Beer,

Everyone that is going to report in has reported in. The resutls are clear. Eductors improve "in tank" mixing. They do so to the point that you can fast load the methanol. Getting the methanol in at the right rate has always been a sticky issue for newbies. With an eductor, you just load it as fast as it will go.

The plastic eductors we tested did not work out due to material compatibility concerns. However, I've discussed how to do this in black pipe in several places.

I do have a box of the adapters in stock and have posted those on my web site at http://www.b100supply.com/Eductor_Adapter_p/150.htm
for those that want to do it in black pipe. I hope to have pictures soon showing how to do the black pipe version on an Apple Turnover.

edit: corrected link

This message has been edited. Last edited by: RickDaTech,

Yes, Eductors work VERY well at mixing. I made one in the machine shop with great success out of mild steel. Really churns the mix. 11gpm through a 1/4" orifice at 45 psi in a 100L tank

quote:

Originally posted by trtmntdude:
been using these with great results.
http://www.biodieselpictures.com/viewtopic.php?p=1094#1094

Can you give me the vendor for those? we just started putting our reactor together, and it has a 4" port that I can put just about anything through.

I don't know where he got his, but here is a similar one:

Eductor