Onsite treatment of craft brewery wastewater

ONSITE TREATMENT OF CRAFT BREWERY WASTEWATER

C. Kinsley1,2, A. Wusiman1, K. Boyle1, R. Delatolla1, B. Abbassi2, T. Davidson2

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1 Civil Engineering, University of Ottawa2 Ontario Rural Wastewater Centre

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Chris Kinsley, Ph.D. P.Eng., ResearchPhotograph of Chris Kinsley

Phone: 613 679 2218 x 609email: ckinsley@uoguelph.ca

Chris Kinsley has worked with the Wastewater Centre since its inception in 1998 and was instrumental in the development of the centre. Chris has developed and delivered over thirty training courses in the agri-food and decentralised wastewater sectors, both within Canada and overseas.Chris is an adjunct Professor at the University of Guelph and a full time Professor at the University of Ottawa, where he teaches courses in environmental management and leads a research program in the field of decentralized wastewater treatment with an emphasis on constructed wetlands. Chris sits on the research committee of the Ontario Soil, Air and Water Research Committee, and chairs the research committee of the Canadian Decentralized Wastewater Consortium. Chris has a PhD of Engineering from McGill University and is a Professional Engineer in the Province of Ontario.

INDUSTRY CHARACTERISTICS

Defining the Treatment Challenge

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EVERYONE LOVES A

GOOD PINT

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Beer and Wastewater Production

■ The number of breweries has increased rapidly over the past decade. There are now 995 breweries in Canada. Most of are small, local operations with 85% producing less than 5,000 hectolitres (hL) of beer per year1 (<10,000 L/d wastewater).

■ Average production of wastewater is typically 7:1 (wastewater:beer production) although this can vary from 3-10:1 based on production methods.

■ To estimate wastewater production volumes:– For new facilities, estimate 7-10 L of wwt per L of beer production– For existing facilities: WWT = Water Use – Beer Production

51. Weersink et al, in Economic Perspectives on Craft Beer, 2019

300

210

995

40 11112180

1

3

60

19

509

6Beer Canada, 2018

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HOW IS BEER PRODUCED ■ STEP 1 – Milling Grain: Different malts are

crushed for extraction of fermentable sugars (called Grist)

■ STEP 2 – Mash Conversion: Grist + heated water + malt enzymes start breaking down starch to sugars

■ STEP 3 – Lautering: Liquid (Wort) is separated from spent grains – VERY IMPORTANT THAT SPENT GRAINS ARE NOT ADDED TO WWT –GREAT FOR ANIMAL FEED

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HOW IS BEER PRODUCED ■ STEP 4 – Kettling: Wort is added to a kettle

where it is brought to a controlled boil then hops are added

■ STEP 5 – Whirlpool: Separate malt and hops particles before fermentation – HIGH STRENGTH SLUDGE BEST SEPARATED AND HAULED (IDEALLY TO A DIGESTER)

■ STEP 6 – Fermentation: Yeast and flavours are added and sugars are converted to beer – WASTE YEAST SLUDGE SHOULD BE SEPARATED AND HAULED

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HOW IS BEER PRODUCED ■ STEP 7 – Maturation

■ STEP 8 – Filtration, Carbonation & Cellaring: –HIGH STRENGTH SLUDGE BEST SEPARATED AND HAULED (IDEALLY TO A DIGESTER)

■ STEP 9 – Bottle washing: High volume, low concentration – Can be diverted directly to sewer (if rinsing clean bottles)

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Wastewater characteristics by process

Source Characteristics Onsite Treatment

Off-site Mgmt

Tank Cleaning (CIP)

3,000-10,000 BODpH 3-12

X

Spent Grain 100,000 BOD30,000 TSS

X

Whirlpool Sludge 85,000 BOD35,000 TSS

X

Fermentation Waste Yeast

100,000 BOD6,000 TSS

X

Waste Beer 100,000 BOD X10

Brewers Association, 2012

Regulatory Requirements

Discharge to a Municipal Sanitary Sewer

■ Onsite Treatment to meet Sewer Use Bylaw limits

Discharge to a Soil Based System

■ If <10,000 L/d require OBC approval and onsite treatment to meet STE limits

■ If > 10,000 L/d require MOECP approval and onsite treatment to meet EA

Discharge to surface water

■ Require MOECP approval and onsite treatment to meet EA

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Parameter Unit Brewery Effluent Composition

Typical Sewer Use Limits

Typical Environmental Discharge Limits

COD mg/L 1,800 – 5,500 - 100 - 125BOD mg/L 600 - 5,000 300 10 - 25TSS mg/L 200 - 1500 300 10 - 25Tot. Nitrogen mg/L 30 - 100 100 10 - 25Tot. Phosphorus mg/L 30 - 100 10 0.1 - 1Temperature °C 15 - 45 60 -pH - 2-12 5.5-11 6.5-8.5

Brewers Association, 2012, Metcalfe & Eddy, 2011; City of Ottawa, 201612

Typical concentrations and Reg. Limits

General Treatment Considerations■ pH control is essential■ Flow balancing is essential■ Nitrogen addition may be required as brewery

wastewater has a high C:N ratio■ High strength solids (spent grain), sludge wastes

(whirlpool sludge and waste yeast) and waste beer need to be diverted from the WWT system.

– One or more holding tanks are required■ Foaming is quite common and an anti-foam

agent or changes in operating procedures may need to be considered.

■ Sludge bulking is also fairly common and can be addressed by reducing HRT / instigating a recycle line.

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BEAU’S ALL NATURAL BREWERY WASTEWATER

CHARACTERIZATION

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Bottle washing and sludge waste sources

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Sample TS (mg/L) COD (mg/L

Bottle Washing 400 400

Yeast Purge 96,300 247,600

Whirlpool Rinse 107,300 132,400

Mash Tun 35,400 45,900

Low strength WW (onsite treatment) and high strength WW (farm AD)

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Flow Characterisation and Balancing

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Average daily flow for days of the week (Sept 2019 to Feb 2020)

Balancing Tank Calculation = 60 m3 with 15% S.F.

Beau’s All Natural Brewing Co. Treatment Train

18Beau’s All Natural Brewing Company, Ltd.

Moving Bed Biofilm Reactor (MBBR)

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LABORATORY EXPERIMENT

Determining System Design Limits

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The Project: Optimize Beau’s

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Parameter Unit Value

Influent sCOD mg/L 2000

HRT hr 3, 4, 12

R1 (Kontact) R2 (K5) R3 (SG)

Varying HRT with constant loading (12 hr HRT)

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55

60

65

70

75

80

85

90

95

100

3 4 12

sCOD

Rem

oval

(%)

HRT (hrs)

BREWERY SYSTEM PERFORMANCE

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Operational Improvements

■ Increased aeration capacity (new blowers) to maintain DO > 2.0 in first reactor

■ Installed a recycle line (R=400%) to increase internal flows.– Washed out filamentous bacteria– Promoted growth of biofilm on carriers as opposed to suspended growth– Reduced sludge production

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MBBR System Performance (Avg ± SD)

Parameter Raw Wastewater MBBR 1 MBBR 2DO (mg/L) - 2.1 ± 0.9 3.7 ± 1.5sCOD (mg/L) 2756 ± 1299 1185 ± 835 467 ± 221NH4

+-N (mg/L) 14.4 ± 12.4 12.4 ± 7.8 9.8 ± 2.8SRP (mg/L) 11.9 ± 6.5 10.5 ± 5.2 8.3 ± 3.1

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• Full scale system is not meeting BOD (sCOD) limit of 300 mg/L. Implementing a balancing tank should improve performance.

• N, P are below discharge limits but exhibit little removal in the system

Conclusions

To properly treat brewery wastewater:

■ Separation, holding tank and hauling of sludge wastes is essential■ pH neutralization is essential■ flow equalization is essential

MBBR Systems:■ Very effective at lab scale at reducing sCOD (>90% removal of 2000 mg/L with 4 hr

HRT)■ Less effective at full scale at reducing sCOD (83% removal of 2750 mg/L with a 36

hr HRT)– Implementing a recycle stream to reduce internal HRT improved sludge settling

and biofilm development and reduced sludge production.

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Acknowledgements

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Support and funding provided by:

Beau's All Natural Brewing CompanyOntario Ministry of Agriculture, Food and Rural AffairsEastern Ontario Water Resources CommitteeNSERC

Thank you

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