The Potential Biogas Value of Industrial Wastewater Christensen.pdfIndustrial Wastewater...

Preview:

Citation preview

Kevin D. Christensen, PE (WI, SC, MD)Senior Project Engineer/Business Relationship Manager

Short Elliot Hendrickson Inc.May 23, 2018

Wisconsin Energy Innovation Summit

The Potential Biogas Value of Industrial Wastewater

Food & Beverage in Wisconsin – By The Numbers• Food & Beverage Processing

– Nearly 1,400 companies– 93,000 jobs– Annual sales $67.8 billion

• Wisconsin Ranks #1 – Cheese production (3 billion pounds)– Organic corn, oats, beans & hay acreage

• Organic acreage in Wisconsin increased by 17% from 2008-2014

Building a Better World for All of Us®

Farms & Agriculture in Wisconsin• Annually generate > $88 billion in economic

activity• Support estimated 413,500 jobs statewide• In 2016, Wisconsin’s fluid milk production

topped 3 billion pounds for the first time

Building a Better World for All of Us®

Farms & Agriculture in Wisconsin• Milk Production

Fluid milk – 3 billion poundsCheese – 3 billion pounds

(30 billion pounds milk at 10% yield)33 billion pounds milk/year

• Animal PopulationUsing 21,000 pounds milk/animal/year:

About 1,570,000 animalsManure production (115 pounds/day for an average Holstein cow)

About 90,000 tons per day (32 MM Tons/yr)

Building a Better World for All of Us®

Farms & Agriculture in Wisconsin

• The 32 MM tons per year does not include beef or replacement herd production

• Manure sources from hog, poultry

• Industrial process wastewater

Food & Beverage Industry Process Wastewater

• Non-contact cooling water• Contact cooling/container

rinse• Batch/cooker cleaning &

sanitation• Canning/bottling/packaging

cleaning & sanitation• Off-spec product/product

residual• Tanker truck/vehicle wash• Floor/facility wash down

Building a Better World for All of Us®

Wastewater Characteristics

• Industrial process wastewater may contain

Building a Better World for All of Us®

• High organic and/or solids loads

• Rapidly changing conditions• Flow• pH• Temperature

• Chemistry which inhibits biological activity• Chlorine• Quaternary ammonia• Peracetic acid

Industrial Wastewater Characteristics

Building a Better World for All of Us®

COD – Chemical Oxygen DemandCOD1 – Municipal measured in Biological Oxygen Demand (BOD)Green-shaded industries underwent wastewater evaluation and segregation study with goal to reduce hydraulic flows to anaerobic digester process

Facil

ity Typ

e

Flow

COD1 mg/

l/day

Lbs/D

ay

Municipal (50,000 pop.) 5.00 250 10,500Pork slaughter 2.00 22,955 382,890Cheese processor 0.50 6,934 28,932Yogurt processor 0.22 12,219 22,432Beverage processor 0.04 1,950 650

Industrial Wastewater Segregation Measures

• Evaluate clean-in-place (CIP) measures to optimize water use– Install sensors in-process to identify

• Product slippage• Valve actuator/equipment malfunctions• pH excursions

– Install sensors at lift station to detect, implement high-strength diversion to flow equalizing/holding tanks• Calibration period required• Coordination between plant process, IT and

wastewater personnel required

Post Segregation Industrial Wastewater Characteristics

Building a Better World for All of Us®

0.07

0.10

0.15

0.40

33300.00

28785.00

2,823

1,362

18,900

24,021

3,534

4,545

0.00 5000.00 10000.00 15000.00 20000.00 25000.00 30000.00 35000.00

Yogurt processor

Cheese processor

Normal Strength Lbs/Day

High Strength Lbs/Day

Normal Strength COD1 mg/l/day

High Strength COD1 mg/l/day

Normal Strength Flow

High Strength Flow

Industrial Wastewater CharacteristicsPost Segregation

• Yogurt Operation– 84% of organic load

captured in 31% of the daily flow

• Cheese Operation– 83% of organic load

captured in 20% of daily flow

0

10

20

30

40

50

60

70

80

90

100

Post Segregation Results

Economics – Cost Avoidance• Flow• BOD• TSS• Phosphorus

Building a Better World for All of Us®

Biogas Potential• Theoretical

– Generally accepted values indicate about 0.7L of biogas will be generated for every gram of BOD reduced (11.2 cubic feet/lb BOD) Testing advised as part of feasibility evaluation

– Biogas Composition55-75% Methane (65%)25-45% Carbon Dioxide (35%)

• Actual results will vary based on temperature, barometric pressure, feedstock composition & feed rate

Observed Results

– COD reduction– 93 – 99+ %

• Biogas generation– 4.3 – 12.5 CF/lb COD reduced– Average 8.3 CF/lb COD

reduced

• Methane content– 45-70%

• Dairy waste digester operation (15 months)

Biogas

Dairy processing waste

Biogas Economics• Dairy waste digester operation

– Organics loading – 42,921 lb/day– Biogas generation – 356,244 cubic feet/day (247 CFM)– Methane content – 231,558 cubic feet/day

• BTU’s available (950 BTU/CF)– About 220 MM BTU/day / 2,200 Therms/day– Value @ $1.185/Therm = $2,600/day ($950,000/yr)

ElectricityDairy processing waste

Costs of Compliance• Anaerobic System

– Force main/Flow equalization– Twin complete mix reactors– Solids/Liquid separation– Biogas conditioning– Biogas storage– Two Jenbacher Type 316 0.84 MW

• One fitted for Biogas/Natural Gas (CHP-start-up)• One Biogas only

– CHP systems (Switchgear & Heat exchangers)

Building a Better World for All of Us®

Costs of Compliance - Continued• Aerobic System

– Anoxic contact basin– Activated sludge process– Clarifier– Sludge thickening/dewatering– Phosphorus removal

• Operations & Maintenance• Annual operating expenses

– Operations labor

Questions

?Building a Better World for All of Us®

SEH Office Locations

• Kevin Christensen, PE262.349.0434kchristensen@sehinc.com

• Visit us at www.sehinc.com• Interact with us on social media

Thank You, and Let’s Stay in Touch!

Recommended