Jump to content
middleofnowhere

Ways to add head to the mash tun

Recommended Posts

Edit: the title should read "ways to add heat to the mash tun". I can't figure out how to edit the title.

This question is related to my rye topic, also in the general forum. Sorry if it's too similar.

I don't know a lot about commercial mash tuns. I'm only going to have access to propane for heat, I can either use a direct flame under my mash tun or steam inject. Steam injection seems scary, I have no experience with it, and I don't want to blow myself up. The concept of a direct flame underneath is pretty straight forward. I'm intending to do a step mash, so I need to add heat to a thick mess. Obviously this will need agitated/stirred, especially if it's over a direct flame.

Can anyone point me in the right direction for my options on direct flame vs. steam injection. What professional setups exist in the ~6 barrel range?

Share this post


Link to post
Share on other sites

Another option to consider is a steam jacketed mash tun. Both steam jacketed as well as steam injection will need a boiler. But with steam injection you'd need to replenish your boiler water a lot more frequently. Direct fire can scorch your mash.

Share this post


Link to post
Share on other sites

Do you already have a steam boiler?

Steam injection is pretty straight forward. You put a steam pipe in the mash tun, and you turn it on. Ok, a bit more than that, but that's the basic premise.

You could look at steam injection as being safer than a jacket, as you don't have a jacket to over pressurize and burst (rare). On the other hand, you are dealing with live steam, so if you are standing in front of a steam line and open it, you are getting burned (also rare).

In my opinion, either of the steam options are safer than having an open flame in a distillery, but that's just my 2 cents.

If given a choice and an unlimited budget - jackets win. If you own a tank you are planning to use, and that tank is not jacketed, or you wish to use the jacket for cooling, steam injection might be a viable option to make good use of an existing tank.

Share this post


Link to post
Share on other sites

Do you already have a steam boiler?

Steam injection is pretty straight forward. You put a steam pipe in the mash tun, and you turn it on. Ok, a bit more than that, but that's the basic premise.

You could look at steam injection as being safer than a jacket, as you don't have a jacket to over pressurize and burst (rare). On the other hand, you are dealing with live steam, so if you are standing in front of a steam line and open it, you are getting burned (also rare).

In my opinion, either of the steam options are safer than having an open flame in a distillery, but that's just my 2 cents.

If given a choice and an unlimited budget - jackets win. If you own a tank you are planning to use, and that tank is not jacketed, or you wish to use the jacket for cooling, steam injection might be a viable option to make good use of an existing tank.

I would respectfully disagree. DIS is going to transfer heat more efficiently than a jacketed system, which means you can get to temps more quickly. Time is money, especially once you start scaling up.

Steam is certainly going to be safer than an open flame, provided you are using and maintaining your equipment properly.

Share this post


Link to post
Share on other sites

Weigh the downsides of DSI - Culinary steam filtration, more frequent boiler blowdowns, possible need for feed water treatment, more aggressive on the boiler life. Steam filtration is a pretty sizable investment if you are moving a good volume of steam. We use a Spirax CSF26 2" on the our DSI feed line - that sucker cost a pretty penny.

We're using a jacket on the still, and DSI on the mash tun - sized at 600 gallons. What we're finding is that speed of temperature increases isn't very linear with DSI. Getting from 55-160 is lightning fast, getting from 160-195 isn't. Also, we're finding that with DSI we top out at about 195F. We can push to 200F, but only if we leave the steam running full out. The problem is, once we hit the mid 190s, we start to get uncondensed steam bubbles breaking the surface, and at 200, the steam educator fails to generate eductive flow and generates large steam bubbles and splashing above the injector. In the jacket, we can easily push to 200 and beyond. Losing a good volume of uncondensed steam out of the tank isn't efficient.

Could we get faster gelatinization running at 212F vs 195F? And that's the time penalty we're paying for only being able to efficiently get to 195F? Need to factor that as well.

It's not so clear cut.

Share this post


Link to post
Share on other sites

If given a choice and an unlimited budget -

I was just going off this. Direct Injection is a better use of heat, heat exchangers are a better use of water and treatment chemicals. Those costs pale in comparison to heating costs.

Capital investments will look like a drop in the bucket compared to running the place for 5 years.

One thing I overlooked with the comment is the size of the vessel being heated. At ~250 gallons I doubt you'd see much if any difference between the two. It looks like you guys are running ~250-500 gallon runs so it may not work well there either. Once you start going big though, jacketed vessels aren't going to compete due to volume:surface area.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×