Advice please with element / controller

[BigWilly]

Hello fellas. I need some help here with my still if anyone can give me some advice that would be great.

The still is a reflux design with the condenser at a 45 degree angle. The column is 2 inch copper, 55 inches long. I went a bit overboard on the condenser- it's a 24 inch long double helix with a cold finger in a 3 inch diameter housing (everything is snug). So I think it will handle almost anything I throw at it!

I'm waiting on some ss fittings for the take off pipe but have been thinking about the other bits and pieces to complete it... So I'm wondering ... :

1. Do people tend to leave the take off pipe permanently connected or disconnect when the column is removed from the boiler? If so, how?

2. I have a 50 litre UK Keg. When I started a few years ago before shelving the project for a while, I bought a 3k element and a Chinese controller (has no markings and I don't know what it can handle - presume I bought it to handle this element). I'm thinking perhaps I should have bought a bigger one - can anyone recommend a size / controller?

3. I still have a good couple of foot of 3 inch copper pipe - seems a shame for it to go to waste - any way to put it to good use??

[still_stirrin]

1. Do people tend to leave the take off pipe permanently connected or disconnect when the column is removed from the boiler? If so, how?

I do. I have the product condenser attached with a copper union. I disassemble, clean, and store separately.

2. I have a 50 litre UK Keg. When I started a few years ago before shelving the project for a while, I bought a 3k element and a Chinese controller (has no markings and I don't know what it can handle - presume I bought it to handle this element). I'm thinking perhaps I should have bought a bigger one - can anyone recommend a size / controller?

A 50 liter boiler would work well with a 4.5k or 5.5k ultra low watt density (ULWD) element...provided you have a power controller to drive it. Input power determines the vapor production rate. For a reflux column, you want good control of the vapor rate to adjust the reflux ratio (which affects production purity). So, bigger input power is a plus, provided you have adequate reflux condenser power to knock it down to reflux back to the column.

As with a potstill, column diameter affects vapor speed. For a reflux column you want the velocity to be slower than for a potstill. But with your 2" column, you should be able to run well at 2kW input power. The bigger element will save time coming "online", but you will need to dial it back for the production...hence, a input controller

3. I still have a good couple of foot of 3 inch copper pipe - seems a shame for it to go to waste - any way to put it to good use??

You could sell it. Somebody could use it for a potstill.

Or, you could make a 3" potstill riser (12" tall is quite adequate), or two. Multiple heads makes stripping and spirit runs much easier....best tool for the job (get it?).
ss

[BigWilly]

Ah thanks for the reply mate.

Just to clarify ... Are you saying the 3k element I already have is adequate but that it will just take a while to heat up? Seems a shame to waste it. It also says on it that it has a thermostat fitted - it will switch off at 65-70 degrees. Is it possible to disconnect/ remove the it?

[still_stirrin]

What is the watt density of your 3kW element?

Most that I've seen are low watt density (LWD) instead of ULWD...it has to do with the watts per square inch of element surface area in contact with the wash. The low watt density are shorter and typically not "return bend" type of elements. What that does is increase the temperature along the surface of the element making scorching more likely. The ULWD elements have more surface area to dissipate the heat, reducing the potential scorching of the wash.

Personally, in a 50 liter boiler (a good hobby sized boiler), I would opt for the 4.5kW or even the 5.5kW simply because you have more (available) power spread over a larger (surface area) element. The low watt density elements, although less expensive, are not as versitile in your boiler.

While you will likely be refluxing using only around 2kW (a function of the column diameter), when running a stripping run in potstill mode, you likely will be pushing much more power. And THAT will give you the risk of a scorch.

I suggest reading the parent site with regard to power input and how that relates to column size and production rates. Getcha' some learnin'.
ss

[still_stirrin]

...It also says on it that it has a thermostat fitted - it will switch off at 65-70 degrees. Is it possible to disconnect/ remove the it?

That's a "deal breaker". I don't think you CAN disable the thermocouple-controlled over-temperature protection. I believe it is built into the element.

Sorry.
ss

[BigWilly]

Damn.

Well I'm stuck with an immersion heater element as I've welded a boss into the keg already to take one, and they look like they only go up to 3kw. Guess I'll have to look for a 3kw without a thermostat ...

[still_stirrin]

Damn...Well I'm stuck...as I've welded a boss into the keg already to take one...

Got the cart in front of the horse, didja? Some lessons are learned the "hard way".

[BigWilly]

Yup. Sure I'll figure it out tho.

[BigWilly]

So how about this?

https://www.amazon.co.uk/gp/aw/d/B01DXG ... ref=plSrch

[BigWilly]

I can use the immersion heater to help get up to temp quickly

[RedwoodHillBilly]

So how about this?

https://www.amazon.co.uk/gp/aw/d/B01DXG ... ref=plSrch

It looks similar to the one that I use, except that it seems to be a bit longer.
https://www.amazon.com/gp/product/B0183KIU1E" onclick="window.open(this.href);return false;" rel="nofollow

[still_stirrin]

Home run! (American jargon for "out of the park")

That wavy ULWD stainless steel element is exactly what you want. And it has British straight threads too (just make sure your thread adapter has the same threads tho). Since you're in the UK, I trust this one is available and would work good for you.

One thing, with the 5.5kW element, it is very doubtful you'd need the 3kW at all. Using it (in addition to) the 5.5kW element would not only be "overkill", but still could result in scorching (because of the low watt density).

Will this 5.5kW element thread into the fitting you've welded into your boiler already?
ss

[Pikey]

Uk "Immersion heaters" are meant to be run fully immersed

Edit: and the "thermostat" is a safety feature to prevent domestic hot water systems from scorching the occupants of the shower to death ! I don't think you can over-ride it - but I hav a broken one - I'll take a look.

If your fixing boss is at the top of the boiler, convert the screw in part of the immersion heater to become an input port, so you can fill the keg without dismantlng the system and cut in for a washing machine heater low down on your keg.

[BigWilly]

Na the bloody boss is right at the bottom. However ...

I could just use the immersion heater element to plug the hole. Could even cut / unscrew the actual element no problem.

Before I go ahead and buy that other element, I'm now without welding equipment so would this do the job??

Look at this on eBay http://www.ebay.c ... ="nofollow

Then there's just the controller to think about ...

[Shine0n]

just replace the rubber gasket with a ptfe gasket and should be good to go.

[Swedish Pride]

hey mate

a couple of thoughts

you have a 55 in 2" reflux build, but you have about the same amount of 3" available to you ( leftover + condenser).
I'd use the 3" to make a packed section and make a 2" condenser for it, it' will increase your takeoff speed compared to a 2" column.

also keep in mind that for a 5.5kw element you'll need a 25amp breaker, I solved this by hooking it up to the cooker ( just means i can't use the cooker at the same time as i run the still.)

Oversize your controller, I had a 10kw china controller melt on me , It might have been the cable but not sure yet.

[BigWilly]

just replace the rubber gasket with a ptfe gasket and should be good to go.

Any problems with wrapping it with ptfe tape instead?

[Pikey]

Ok Here's the two wosrt pictures ever :

1) Immersion heater

Thermostat top

IN photo 1 there should be 3 tubes visible but the thermostat one is exactly behind one of the heater tubes.Clearly the wires could be connected simply to the two heater tubes and thus the thermostat would be bypassed simply enough.

In photo 2 you can see where the live goes to the thermostat. then the output from that, a white wire goes to the input side of teh heater element. So if your immersion is of this type and you have fitted it at the bottom, it should be easy to bypass and useable with a controller.

Sorry about the crap photos !

[BigWilly]

hey mate

a couple of thoughts

you have a 55 in 2" reflux build, but you have about the same amount of 3" available to you ( leftover + condenser).
I'd use the 3" to make a packed section and make a 2" condenser for it, it' will increase your takeoff speed compared to a 2" column.

also keep in mind that for a 5.5kw element you'll need a 25amp breaker, I solved this by hooking it up to the cooker ( just means i can't use the cooker at the same time as i run the still.)

Oversize your controller, I had a 10kw china controller melt on me , It might have been the cable but not sure yet.

Ah mate you're talking absolute sense here and I hate you cuz I really don't want to change designs now I've built the column!

[BigWilly]

Right Pikey nice one mate i'll bust mine apart now and have a look!

[BigWilly]

Yep. Same with mine - easy to bypass the thermostat. Reckon I should give this a go before spending out on more gear. If it's a fail I know what I need to buy anyway ... Thanks a million Pikey mate

[markieb]

if its a fail then its only a fail youve not lost anything but have gained info what not to do.
i brought a cheap ebay chinese element a 3k and 4k element problem i found was couldnt find the right nut to solder on so made a housing for the 1 1/2 from copper plate and some copper tube just soldered it together and onto tthe keg seem water tight lol.
the controller im using is a ebay 10,000w scr and its a beaute holds my 4kw element where ever i want it also controls my 3kw catering boiler i scored for free from a school throwing it out off with the thermostat and wired straight in to the element works a treat.got alot of the water carbouys from a secondry school too for (brewing beer) technically i am as i only use them for fermenting but theyre ideal.