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American Meat Institute Conference on Worker Safety, Human

Resources and the Environment Kansas City, Missouri

Brian Mulinix, P.E. Brian Bakke, P.E. HDR Engineering, Inc. March 20, 2013

Wastewater Design &

Best Practices

(2)

Overview

Wastewater – what are we treating

Preliminary Treatment

Anaerobic Treatment

Aerobic Treatment

Nitrogen Removal

Phosphorus Removal

Tertiary Treatment

(3)

BOD

5

TSS

FOG

TKN

Phosphorus

Proteins

Fats

Carbohydrates

Partially-Digested

Feed

Manure

Urine

What Are We Treating?

OR

(4)

What are We Treating?

• Slaughterhouse

– Proteins (blood, meat, etc.)

– Fat

– Partially digested feed from stomachs and intestines

– Manure from pens

– Urine from pens, kidneys, bladders, etc.

• Processing

– Proteins

– Fat

– Carbohydrates

• Animal Feeding Operations

– Manure

– Urine

(5)

What Type of Food is Being Treated?

Example Protein Fat Carbohydrates

Slaughterhouse Processing

•Hams Some Some (from the pickle liquor)

•Bacon Little (from the pickle liquor)

•Cooked Sausage Little

•Chicken-Fried Steaks (from the breading)

Rendering

(6)

Pretreatment Can Shift Type of Food

DAF reduces fat and some protein

Ferric pretreatment greatly reduces both fat and

protein

Many carbohydrates

– Go into “true solution”

(7)

Determine Waste Loads from Food

Protein BOD

5

= TKN x 6.25 x 0.8

Fat BOD

5

= FOG x ( 1.7± )

Carbohydrate BOD

5

=

(8)

Why is Type of Food Important?

Anaerobic Sludge Production

pH Buffering

– Proteins make their own alkalinity

– Fats and carbs require alkalinity for buffering

Nutrient Requirements

– Proteins are a complete food source

– Fats and carbs are deficient in nutrients and micronutrients

Different Physical Characteristics

– Fats may coat media, float

Fat Protein Carbs 1 1.5 - 2 4 - 5

(9)

Swine Farms are Slightly Different

Swine farm waste is similar to human waste without

the dilution water

Virtually everything has been through digestive or

urinary tract

Pigs have utilized much of readily-digestible food

(energy), leaving less easily-digestible to treat

(10)

What is Your Discharge Requirement?

Municipality

– Limits specific to system

– Surcharges

Land Application

– Agronomic rates

Direct Discharge

– Effluent guidelines – Nutrient limits

(11)
(12)

Screening

Remove solid materials, prevent avoidable BOD

and TSS

Types:

– Static Screens – Vibrating Screens – Rotary Screens – Channel Screens

(13)

Gravity Clarifiers

Removal BOD 20-30% TSS 30-40% TKN 10-20% FOG 50-60%

(14)

Dissolved Air Flotation

Removal Without Chemicals With Chemicals BOD 30-40% 60-80% TSS 50-60% 70-80% TKN 20-30% 40-60% FOG 50-70% 70-90%

(15)
(16)

Anaerobic Treatment – A Marvelous Tool

Reduce CBOD

5

by 85-90%

Reduce TSS by 70-80%

Biogas produced containing 74±%

Accept/treat shock organic loads

Serves as equalization

Accomplishes with minimal energy required and

(17)

Anaerobic Degradation of Organic Materials

Acid-Forming Bacteria Methane-Forming Bacteria Complex Organics Organic Acids Methane + CO2 + small

amt. Cell Mass

Waste Conversion

(minimal energy lost, minimal BOD reduction)

Waste Stabilization

(waste energy converted to methane energy, big BOD

(18)

Anaerobic Treatment Technologies

Low Rate

– Anaerobic lagoon

Medium Rate

– Anaerobic contact system

– Anaerobic SBR

High Rate

– Upflow Anaerobic Sludge Bed (UASB)

– Anaerobic filters; upflow, downflow, expanded bed

(19)

Anaerobic Treatment Comparison

Low Rate Medium Rate High Rate

Process/Reactor Lagoon

Contact

process ASBR UASB Filters Loading,

lbs BOD5/1000 ft3/day 15 – 30 60 – 160 60 – 375 >160 160 - 625

HRT, days 3.5 – 15 1 – 10 0.5 – 10 0.25 – 1.5 0.5 – 2.0

SRT, days unknown,

but long >20 >30 >100 30-100

In summary, anaerobic lagoon is lightly loaded with a long detention time and sludge age – and all the more robust for it

(20)

Covered Anaerobic Lagoon

Storm Water Collection Synthetic or

Natural Cover

Peripheral Biogas Collection

(21)

Design Considerations / Common Operating

Problems

Solids Accumulation

– FOG at lagoon < 350 mg/L

– Prevent sand, mud, grit, paunch manure, pen waste,

truck bedding, etcL keep out of lagoon

– Measure/plot grease cover and settled sludge thickness Spring, Summer and Fall

– Remove sludge every Fall to maximize active volume

– < 15% of WAS digests in lagoon, serves more for thickening; remove WAS sent 1-2X/year

(22)

Design Considerations / Common Operating

Problems (cont.)

Anaerobic Temperatures

– Ideally 95°F

– Can go as low 82-86°F, or lower for shorter periods

Chemicals

– Chlorides: sudden swings of > 1,200 mg/L may disrupt anaerobic treatment

• Processing plants with brine chills, pickle liquors

(23)

Design Considerations / Common Operating

Problems (cont.)

• Chemicals (cont.)

– Sulfates/Sulfides

• Sulfates typically from water supply

– Ferric sulfate in pretreatment

– Processing mucosa

– Tannery wastewater

• Sulfates in anaerobic influent reduced to hydrogen sulfide

– Reduces methane generation

– At high concentrations can be toxic to methanogens

» Rule of thumb – COD:S < 4:1

– Most in effluent, but released in biogas (depending on pH and temperature)

– For every 26 mg/L H2S in the liquid, 1% in gas phase (35⁰C)

– For each 1 mg/L sulfide in effluent, requires 2 mg/L of dissolved oxygen to oxide back to sulfate

(24)

Design Considerations / Common Operating

Problems (cont.)

Chemicals (cont.)

– Quaternary Ammonium Compounds (Quat)

• Inhibitory levels at 5-15 mg/L active ingred.

– Macronutrients: nitrogen, phosphorus, potassium

– Micronutrients

• Cobalt, copper, manganese, molybdenum, nickel

(0.1 mg/L deficient)

(25)

Meat Processing Plant

Anaerobic Lagoon Effluent

30 40 50 60 70 80 90 100 0 500 1000 1500 2000 3 /4 /0 7 4 /1 5 /0 7 5 /2 7 /0 7 7 /8 /0 7 8 /1 9 /0 7 9 /3 0 /0 7 1 1 /1 1 /0 7 1 2 /2 3 /0 7 2 /3 /0 8 3 /1 6 /0 8 4 /2 7 /0 8 6 /8 /0 8 7 /2 0 /0 8 8 /3 1 /0 8 1 0 /1 2 /0 8 1 1 /2 3 /0 8 1 /4 /0 9 2 /1 5 /0 9 3 /2 9 /0 9 5 /1 0 /0 9 6 /2 1 /0 9 8 /2 /0 9 9 /1 3 /0 9 1 0 /2 5 /0 9 1 2 /6 /0 9 1 /1 7 /1 0 2 /2 8 /1 0 4 /1 1 /1 0 5 /2 3 /1 0 T e mp e ra tu re F ) C B OD (mg /L )

CBOD mg/l Volatile Acids TEMP (ºF)

Micronutrient Addition

(26)

Reactions to upsets, not

causes:

Drop in biogas

production

Low pH

Increase in ORP

High volatile acids

Increased

acid:alkalinity ratio

If performing poorly,

check:

New plant operations,

like processing mucosa

Temperature

Quats

Sudden chloride swings

Nutrients and

micronutrients

(27)
(28)

Aerated Lagoons/Basins

• Hydraulic and Sludge detention time 1-5 days

• Detention time, not oxygen transfer rate dictates size

• As CBOD5 drops, TSS climbs due to microorganism growth

(29)

Advantages

Simple to operate

No sludge to handle

BOD reduction

• 50% in winter • ≥75% in summer

Convert anaerobic

effluent to aerobic

Nitrify NH

3

under

certain conditions

Disadvantages

Electrical energy req’d

TSS increase

Nitrification requires

• Longer detention time

• Temperatures > 50°F

Small influent flows

require vertical-wall

tanks

(30)
(31)

Activated Sludge Process

Aeration Clarification Biomass Recycle Biomass Waste

Activated Sludge is like a loop with no beginning and no end

• Continuous or semi-continuous – CBOD oxidation

– Nitrification

• Represents most wide-spread used in meat and poultry industries

• Conversion into settleable solids

• Develop ideal biomass

• Balance of floc and filament-forming organisms

Influent

(32)

BOD Only Activated Sludge

Design Parameters to consider

– Dissolved oxygen supply – Maintain 2.0 mg/L DO

– Alkalinity – Maintain pH 6.5 – 7.9

– Detention/contact time – 4 to 8 hours

– Mixed Liquor Concentration – 2,000 to 3,000 mg/L

– Oxygen Uptake Rate – 40 to 50 mg/L/hour

– Sludge age – 1 to 3 days

– Temperature range – 10 to 30 deg. C.

Consumes:

(33)

Typical Meat Industry Activated Sludge

Aeration Basin Final Clarification

RAS

WAS Anaerobic Lagoon

Anaerobic Influent Anaerobic Effluent

Pork/Beef Poultry Meat Proc. Pork/Beef Poultry Meat Proc.

CBOD5(mg/L) 1200-1300 600-1800 600-1600 200-400 150-250 150-250 TKN (mg/L) 120-300 60-180 50-150 110-270 55-160 45-135 Nitrate/Nitrite (mg/L) ≤4.0 ≤4.0 ≤4.0 0.0 0.0 0.0 Phosphorus (mg/L) 20-50 15-30 20-45 18-45 13.5-27 18-40 BOD:N:P 100:10:1.67 100:10:1.67 100:10:3.0 100:60:10 100:50:10 100:40:14

(34)

Ammonia Nitrification

• 2-step conversion

– Ammonia to Nitrite - Nitrosomonas

– Nitrite to Nitrate - Nitrobacter

• Design Parameters to consider

– Dissolved oxygen supply – Maintain 2.0 mg/L DO

– Alkalinity – Maintain pH 6.5 – 7.9

– Detention/contact time – 4 to 24 hours

– Mixed Liquor Concentration – 3,000 to 5,000 mg/L

– Oxygen Uptake Rate – 40 to 50 mg/L/hour

– Sludge age – 8 to 15 days depending on temperature

– Temperature range – 10 to 30 deg. C.

Consumes:

4.57 g O2 / g NH4-N

(35)

Traditional Nitrification/Denitrification

25% O2 25% O2 40% Carbon (BOD) 40% Carbon (BOD) 60% Carbon (BOD) 60% Carbon (BOD) Nitrification-Aerobic Denitrification-Anoxic 4.57 g O2/g NH4-N oxidized 3.5-6 g COD/g NO3-N reduced 7.14 g CaCO3/g NH4-N oxidized

recover 3.57 g CaCO3/g NO3-N reduced

1 mol Nitrite (NO2-) 1 mol Nitrite (NO2-) 1 mol Nitrate (NO3-)

½ mol Nitrogen Gas (N2) 1 mol Ammonia (NH3/ NH4 +) Autotrophs Heterotrophs 75% O2 75% O2

(36)

Nitrogen Removal Processes

Single Stage Nitrification-Denitrification

Simultaneous/Combined Nitrification Denitrification

Sequential BOD-Nitrification-Denitrification

Biological Options

– Suspended Growth

(37)

Nitrogen Removal Processes - Classic

Zoned

Wuhrman

Ludzack-Ettinger

Modified Ludzack Etinger (MLE Process)

Bardenpho

(4 stage Phoredox)

Step Feed

Tilmann WRP, Los Angeles

Effluent:

NH4-N < 1 mg/L TN < 10 mg/L

(38)

Nitrif/Denitrif: +70% TN Removal

Modified Ludzack-Ettinger (MLE) system

Aeration Basin Final Clarifiers RAS (1Q) WAS Anoxic Basin

Mixed Liquor Return (4Q) (nitrate source) From Anaerobic Lagoon TN 200 mg/L 40mg/LTN Carbon Alkalinity

(39)

0% 20% 40% 60% 80% 100% 0 2 4 6 8 10

Recycle Ratio (RAS + MLSS)

(40)

Nitrif/Denitrif: 6-8 mg/L Effluent TN

Aeration Basin Final Clarifiers RAS (1Q) WAS Anoxic Basin

Mixed Liquor Return (4Q) (nitrate source) From

Anaerobic Lagoon

4-Stage Bardenpho system

TN 200 mg/L 7 mg/LTN Carbon, Alkalinity Post-Anoxic Basin Reaeration Basin Carbon TN 40 mg/L

(41)

Pork Plant – Effluent Nitrogen

0 5 10 15 20 25 30 35 40 45 50

1-Nov-08 3-Jan-09 7-Mar-09 9-May-09 11-Jul-09 12-Sep-09 14-Nov-09 16-Jan-10

To ta l N it ro g en , m g /L Effluent TN

Probably lost nitrification

Switched from Final Clarifier to UF Membranes Influent TKN averaged 199 mg/l

(42)

Simultaneous Nitrification/Denitrification

Biological process occurring concurrently in same

reactor

Relies on dynamic balance of DO/BOD/NH

3

Utilizes control of aeration by DO or ammonia

concentration

Reduces oxygen requirements and recovers

alkalinity

(43)

Simultaneous Nit/Denit

25% O2 40% Carbon 60% Carbon Nitrification-Aerobic Denitrification-Anoxic 1 mol Nitrite (NO2-) 1 mol Nitrite (NO2-) 1 mol Nitrate (NO3-)

½ mol Nitrogen Gas (N2) 1 mol Ammonia (NH3/ NH4 +) Autotrophs Heterotrophs 75% O2 3.43 g O2/g NH4-N oxidized 2.1-3.6 g COD/g NO3-N reduced 5.7 g CaCO3/g NH4-N oxidized

(44)

Nitrogen Removal Simultaneous

SBR

Oxidation Ditch

Biodenitro

– Cyclic Aeration

Two Zone Activated Sludge with DO Control

Effluent:

NH4-N < 4 mg/L TN < 6 mg/L

(45)

Simultaneous Nit/Denit

SND Basin Final Clarifiers RAS (1Q) WAS From Anaerobic Lagoon Carbon Alkalinity Post Aeration NH3 / DO Control

• Target effluent NH3 in first stage

• Target DO in first stage 0.01-0.15 mg/L

(46)

Potential Advantages

Elimination of

separate tanks,

internal recycle

Simpler process

design

Reduction of carbon,

oxygen, energy, and

alkalinity

consumption

Potential Disadvantages

• Limited controlled aspects of the process

• Floc sizes

• Internal COD storage

• DO profile within floc

• Slower Growth Rates

• Larger Tank Sizes

• Sludge bulking,

filamentous bacteria growth

• Complex instrumentation

(47)

Anammox

25% O2 40% Carbon Nitrification-Aerobic Denitrification-Anoxic 1.83 g O2/g NH3-N oxidized 0 g COD/g NO2-N reduced 3.1 g CaCO3 /g NH3-N oxidized 1 mol Nitrite (NO2-) 1 mol Nitrite (NO2-) 1 mol Nitrate (NO3-)

½ mol Nitrogen Gas (N2) 1 mol Ammonia (NH3/ NH4 +) Autotrophs Heterotrophs 40-50% O2 75% O2 60% Carbon

(48)

Definition

Developed in Europe

Bacteria

• Autrophic – Use CO2 as Carbon

Growth Conditions

• Anaerobic/Anoxic

• Temperature 20-35°C

• Very slow growers –

– Long sludge age > 30 days

• NH4+ : NO2- ratio ≈ 1 : 1.32

– pH (neutral range)

– Nitrite (maintain at <40 mg/L)

– Free Ammonia (maintain at <10 mg/L)

• Once Grown Very Stable - Can be stored for months with no food.

(49)

Anammox Providers

Paques BV

– Upflow gravity separation

Anita Mox

TM

by Veolia Water Technologies

– Plastic biofilm carriers

– Similar to MBBR

DEMON

®

by World Water Works

– WAS cyclone separation

(50)

Anammox (DEMON

®

)

Operational Philosophy

1 process cycle of the DEMON involves 4 time-controlled phases:

• Aeration phase

• Fill / React phase

• Settling phase • Discharge phase Standard Effluent 90% removal NH4-N 10% production NO3-N 80% removal TN

(51)

Full Scale Operation

Regular sampling

Sensors: pH, DO, conductivity,

NH

3

-N

Regular Operation

– DO range of 0.3-0.4 mg/L

(during aeration phase)

– pH typically 7.0

Avoidance nitrite accumulation

(52)

DEMON

®

Design Requirements

Pretreatment

– Most BOD, TSS removed

– Pre-storage tank (6-12 hrs HRT)

Design parameters

– Total/soluble COD, TKN, NH3-N, Alkalinity, PO4-P, TSS, Temperature, pH

– Flow (aver/max); sludge processing

Tank reactor

(53)

DEMON

®

Major Components

Seed Sludge Aeration

System

Instruments & Controls

Tank

(54)

Comparison

N2 CO2 emissions > 4.7 t CO2/t N NO3 C-source 2.3 lb Methanol/lb N NH4 Energy 1.27 kWh/lb N Nitrification/Denitrification N2 CO2 reduction -0.4 t CO2/t N NO2 / NH4 C-source 0 lb Methanol/lb N NH4 Energy 0.50 kWh/lb N

DEMON®-system

(55)

Demon Results - Sidestream

Heidelberg, Germany

(56)
(57)

Biological Phosphorus Removal

Many Process Options

Anaerobic Zone key to process

– Grow Phosphorus Accumulating Organisms (PAOs)

Typically achieves <1.0 mg/L

High influent Sol BOD/P is required

– carbon/VFA addition via fermentation

Process stability is key. Conditions that favor the

right PAO populations are need to be understood

(58)

Biological Phosphorus Removal

Modified (5-stage) Bardenpho

UCT Modified UCT VIP (Virginia Initiative Process) Effluent: TP < 1 mg/L OP < 0.5mg/L

(59)

Chemical Phosphorus Removal

Chemical Options

– Ferric Salts (Ferric Chloride, Ferrous Chloride)

– Alum

– Sodium Aluminate

– Lime

Reaction: FeCl

3

& PO

4

FePO

4

& 3Cl

Dosage: Theory : 5.24 lbs FeCl

3

/ lb P

Actual: 10.48 lbs FeCl

3

/ lb P

(60)

Typical Chemical Treatment Opportunities

Primary Secondary Tertiary Polish

Solids Processing

(61)
(62)

Tertiary Treatment

Treatment Goal – Remove additional TSS, TN, TP

not captured in secondary treatment processes.

Simple TSS Removal

– Tertiary Clarifier

– Cloth Filter Disk

– Sand Filter

More Complex

– Membrane Bioreactor – Ultra Filtration – RO

TN Removal

• Biologically Active Filter (BAF)

(63)

American Meat Institute Conference on Worker Safety, Human

Resources and the Environment Kansas City, Missouri

Brian Mulinix, P.E. Brian Bakke, P.E. HDR Engineering, Inc. March 20, 2013

Questions?

Wastewater Design &

Best Practices

References

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