An update on my brewery is quite overdue. Many changes have been made in the year+ since my last post on this in early 2017.
Ultimately, what triggered the changes I describe below was the fact that I wasn’t quite happy with my implementation of the Kettle-RIMS (K-RIMS) design. Couple reasons for this:
- In some beers I was detecting astringency, which I chalked up to the amount of grain that made it into my boil kettle during mash recirculation (and stayed in my boil kettle). One way of countering this is to do a mash tun only recirculation -- bit of a vorlauf before the usual K-RIMS recirculation. Only problem with this being that I experienced massive temperature loss during that (one of the downsides of stainless plumbing vs. silicone hose), defeating the purpose of my recirculating mash system perhaps entirely. I was able to get better temperature stability if I slowly added hot water inline into the mash runnings during this initial recirculation. Pretty complicated though, especially when trying to control mash pH. I couldn’t easily automate to hit my target temperature either.
- There were annoyances in trying to balance flow rates during recirculation. I used two pumps with sanitary diaphragm valves for this purpose, but even with this precision adjustment I was not satisfied, and it felt as I could not leave the system unattended at all during mashing. The one time I did leave the system unattended for a couple minutes, I ended up dry firing and destroying my heating element. I really should’ve had at least one float switch in this design to protect the heating element. I looked into this, and I ended up starting to go down the road of volume sensing and a software implementation instead. I should’ve also had float valve like the Blichmann autosparge to permit me to match my flow rates more easily. I was close to going that route but I had some concerns with supporting multiple batch sizes, session and imperial beers equally, so ultimately, didn’t.
If you want to want to run a K-RIMS, I have a couple suggestions:
- Use a centre drain boil kettle to bettle allow flushing of grain particles during mash recirculation.
- Size your mash tun to allow “full volume mashing” such that all water chemistry adjustments can be done in bulk in the mash tun, before recirculation begins.
- Use a Blichmann autosparge to simplify flow rate matching.
- Protect your element with a float switch.
My favourite thing about tri clamp fittings is how easy it is to prototype new system ideas. I ended up doing almost a complete redesign of my brewery, but only needed a couple new fittings to pull it off. While settling on a “final” design, I tried dozens of different variations. Seriously. The idea was this:
- Ditch the K-RIMS design, and build a more conventional RIMS brewery with an inline heating tube (often called a RIMS tube).
- Reduce batch size slightly, to support full volume mashing in a single vessel.
- Replace my two pumps, and my two diaphragm valves with a single pump which I could control the speed of with VFD.
Really, the pump was the heart of this redesign. It is a true sanitary centrifugal pump, with a 3 phase 1/2 HP TEFC motor. When a deal came up on it Fall 2017, my plan was put into motion.
This pump was ultimately coupled with a Toshiba variable frequency drive I picked up off of ebay, converting my single phase power to three, and providing plenty of control over pump speed, torque, acceleration/deceleration, etc. I probably wouldn’t have had much success with this it weren’t for bouncing ideas off friends in my homebrew club True Grist. The combination is dead quiet, especially when compared to the base model chugger pumps. Video of initial tests with the pump below. I figured out later that the flow rate in this video was principally limited by the proximity of the pick up tube to the bottom of the kettle. I ended up adjusting this to allow for an even more voracious whirlpool. Really helps in wort chilling with my immersion chiller, as well as extraction of flavour and aromatic compounds from hops (I like to think).
After playing around with the plumbing configuration for months, below is what I came up with.
I built a brew stand out of scrap lumber to support the configuration -- idea being that this would allow for further modifications and tweaks if found necessary after a couple brews at no cost. Eventually I may replace this with a welded SS stand, but for now I am perfectly happy with it.
5″ casters were added to make it easy to move around my pitted garage floor.
What’s next -- hopefully nothing major for a while! Each time I modify my brewery, it ends up snowballing a little bit, and I’m offline, without homebrew for months on end. The system is working quite well now. If I were to make any modifications it would likely be with my mash tun -- perhaps adding a mash stirrer, or a wedge wire false bottom. Some insulation to the mash tun would be helpful as well. I have a sanitary 4-20ma pressure transducer I intend to test for the purposes of volume sensing -- that’s on the list too!