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  • 1.  CO2 usage tracking by application

    Posted 05-22-2023 15:32

    Hi all,

    In an effort to reduce our CO2 usage I would like to track how much we use by department/application (e.g. carbonations, tank purges, canning line, etc.) to see where we can be saving.  I figured flow meters were a good place to start, but am not sure on type or where to place them in line.  We currently have lines going through a pressure regulator on the wall, and that's it for flow control. 

    Does anyone use flow meters to track CO2 usage by application? What flow meters do you recommend? Where do you install them?  Any advice on where to start is appreciated.

    Thanks,



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    Kelly White
    Country Boy Brewing
    Georgetown KY
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  • 2.  RE: CO2 usage tracking by application

    Posted 05-23-2023 13:43
    Hello,
    We have had success using IFM Gas Flow Meters and currently run one with our inline carbonation system.  You need to create a power source for it but prior to the permanent installation we took it around to collect data on different processes that utilize CO2 and gathered information that helped us properly size our HX fromour bulk tank.

    --
    Hal McConnellogue
    Drake's Brewing Company
    Sustainability Manager







  • 3.  RE: CO2 usage tracking by application

    Posted 05-23-2023 20:07

    Chiming in with some recommendations but also to keep tabs on what others suggest. We are actively trying to quantify the overall CO2 usage of our plant. 

    We use an Dwyer rotameter to measure average gas flow during tank purges. You can hook it up to the bottom of the tank for purge, set your regulator, note your flow and then multiply Lpm x total purge time. 

    We have a similar flowmeter to Hal's IFM on our can line seamer (SMC brand). This has been the most enlightening but its hard piped into the underlid gasser. While we new canning lines are big users of CO2, we have since found >50% of our plant CO2 is consumed at the can filler and the majority of that (~67%) is consumed at the seamer. For what its worth, we've also found a strong negative correlation between under lid gasser CO2 flowrate and TPO but there is an upper limit of 340 L/min where we hit diminishing returns. We found 300-320 L/min is optimal but that is obviously a lot of CO2. Off topic, but we are currently using N2 at the seamer and seeing no negative impact on TPO (~35ppb). 

    Excited to see what others suggest. 



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    Campbell Morrissy
    Head Brewer
    pFriem Family Brewers

    PhD Candidate
    OSU - Barley Project
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  • 4.  RE: CO2 usage tracking by application

    Posted 05-24-2023 10:29

    This is a great suggestion, even if tank purges turn out to be a lesser CO2 draw, at least we know.  I'm curious about our canning line now, since we have adjusted the underlid gasser and bubble breaker pressures in the past, to see if that's also our biggest use of CO2.  Also, good to know that N2 is a viable option at a potentially major usage point.  With N2 replacing CO2 in such a significant volume, did you have to install a bulk tank for it, or hard pipe a new line to the seamer to run it on a separate gas from the rest of the canning line?



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    Kelly White
    Country Boy Brewing
    Georgetown KY
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  • 5.  RE: CO2 usage tracking by application

    Posted 05-24-2023 20:23

    Hey Kelly. Admittedly running N2 is a short-term solution to our current CO2 allocation. We are running off a trailer mounted bulk tank and have a soft line running over to the canning line. While we will return to CO2 when the allocation lifts (due to cost), this has accelerated our interest in using N2 as a permanent gas supply to our seamer. We did try using liquid dewars first and they couldn't keep up. The flow rate is high enough that you need a robust vaporizer (the trailer mounted tank has an ambient vaporizer) and simply the dewars don't hold enough (~20 min of canning at 160cpm). 

    This is all pretty new to us and we went for it as a stopgap measure but overall have been really happy. We are currently exploring N2 generation for a longer term solution. Would love to hear others experience. 



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    Campbell Morrissy
    Head Brewer
    pFriem Family Brewers

    PhD Candidate
    OSU - Barley Project
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  • 6.  RE: CO2 usage tracking by application

    Posted 05-24-2023 10:29

    Thanks for the recommendation. We may want to start with one in-line meter just to track between cellar and canning line to get a broad sense of where to focus further efforts.



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    Kelly White
    Country Boy Brewing
    Georgetown KY
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  • 7.  RE: CO2 usage tracking by application

    Posted 05-25-2023 17:01
    Edited by Andy Tveekrem 05-26-2023 08:45

    Howdy Kelly!
    Following along with Campbell, I'm curious what others have done here as well. 
    We've been diving into CO2 usage and mapping quite a bit this year, as we've been constantly in a Force Majeure since December, often cut to only 35-40% of our contracted allocation.

    We did a fairly broad exercise earlier this year diving into some measurements, calculations and assumptions around CO2 usage. 

    1. 60% of our known usage is going to Packaging 
    2. 30% going toward Carbonation and De-aerated Water creation
    3. 7% to Dry-Hop operations
    4. 3% going toward Tank Purges 

    However, all of that known usage only accounts for about 50% of the CO2 that we purchased. So we can somewhat assume that we are losing about 50% of our CO2 to leaks throughout the plant, or some mis-guided assumptions around usage. 

    • Our plant-wide CO2 network is about 10 years old at this point, is largely located outside, and incorporates both plastic and stainless components.
    • We wound up finding that some of our PRVs were detonating well below their setpoint, and were just leaking constantly. 

    Like Campbell suggested, we've been able to reduce Canning usage by about 20% as we've moved toward turning the Bubble Breaker off nearly entirely, and even reducing the usage of the Undercover Gasser. We also saw a bit of an inverse bell curve, where significantly reduced or significantly increased CO2 usage improved TPO results, but hanging out in the middle actually caused worse TPO levels. 

    I know you weren't asking for CO2 reduction suggestions, but just tossing out that most folks don't think about Microbiology as related to CO2 usage, but it can be a huge driver of reduced usage. We have yet to install any sort of pasteurization equipment, and are still able to follow the rules below:

    • If you have clean processes, you can likely re-fill your Brite Tanks without cleaning several times. 
      • We typically Caustic clean our BBTs only about every 60-80 fills. 
      • For Filtered product, we will run Acid (Nitric/Phos) CIP + PAA Sani every 3-4 fills. We run this CIP cycle under pressure, so there is no venting of CO2 or purging after the CIP. We will check the O2 level in the headspace after CIP, and do some minimal purging if needed, but typically no purging is required
      • For Centrifuge-Only product, we will do a quick DA rinse after each fill to prevent yeast/solids accumulation in the bottom, but then will still refill 3 times before Acid/Sani
    • If you are moving beer to your Packaging cellar via pump, you can connect the Headspace of your Fermenter and Brite Tank together to conserve CO2.
      • Rather than pushing with CO2 or using it to replenish the headspace in your Fermenter, if you use a clean hose to connect the headspaces together, you will not need to vent CO2 during the transfer process.
      • If you have concerns with Micro, this is less likely a viable option

    On the note of Nitrogen use, we're pushing ahead. 

    • Trials using Nitrogen gas for purge/flush at the can line showed it was 99% as effective as CO2 gas on a cubic foot basis (you can't directly compare kg to kg as Nitrogen is a less dense gas)
    • Trials using Nitrogen as a push gas for Dry Hopping operations were completely successful. Only issue when using Dewars was getting enough of a flowrate
    • Trials using Nitrogen for purging tanks showed it was as effective as CO2 if you are avoiding turbulent flow
    • Nitrogen generation seems to be the most cost-effective option, as long as you size accordingly for peak flow
      • Reports from others in the industry have stated similar. Purity is great until you start stressing the system
      • Some N2 generation systems have the ability to supplement the pressure with a dedicated N2/CO2 tank. Basically if the N2 generator cannot keep up, rather than compromising on the quality of the N2 produced, it will open a valve to allow the system pressure differential to be made up from a dedicated purchased CO2/N2 tank
    • CO2 recovery operations may require significantly more Electricity to run than would be assumed.
      • For us, the cost of the electricity to run the system will almost equal the price we're currently paying for CO2, plus the ~$2m install cost

    Please reach out for any additional questions, happy to share some data where I can. Hoping to have a N2 generator installed over the summer, will try to report back once we're up and running. 



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    Thanks!

    Sam Thompson
    Quality Manager & Innovation Coordinator
    Lagunitas Brewing Company
    sam.thompson@lagunitas.com
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