Copyright is owned by the Author of the thesis. Permission is given for a copy to be downloaded by an individual for the purpose of research and private study only. The thesis may not be reproduced elsewhere without the permission of the Author.

Thus says the Lorl_' : !lLet not the "rise man glo . . y i:' his wis(!om, Let not the mighty man g:_ory in his m�.ght , Let not the rich man glo�-y i::-: his ric. es;

But et him who g' ories glory ::n this , That he kno -s and unders�and3 me , That I am t,e Lor( who p'. acLse Steadfast lrwe, jL'stice, and righteour:<ness in the (. �:::-th; For in thes" things I de� igb ; ."

, eremiah 9 v •• 24

STUDIES I N ANAEROBI C/AEROBI C TREATMEHT

OF

DAIRY SHED EFFLUENT

A thesis p resented in part ial fulfilment of the

r equ irement for the degree of

DOCTOR OF PHILOSOPHY

in

Agricul tural Engine ering

At Massey Universi ty

Palm e rs ton N orth

N ew Z ealand

DAVID JOHN WARBURTON

1977

A1::S T HACT

I ncreases in herd size and enforcement; of water quality regulations

have crea�;ed an effluent disposal problem for the New Zealand dairy

indus try. Spray disposal to land and lag,)oning are c ommonly used but

mechanical failures, management requirements and p ressure on land have

limited their suitability in many situati,)ns. This project vias

established to consider an alternative system.

Initial studies revealed that anaerobic treatment in unmixed,

non-insulated tanks, followed by trickling filter aeration, might be

sllitable. Two laboratory scale and one field treatment plant ( 1 / 1 5 -

1 /20 full scale) were constructed to investigate the system. A

factorial experimental design allowed investigation into three

anaerobic treatment levels with a 3 x 3 aerobic treatment interaction

nested wi thin each anaerobic treatment.

Anaerobic residence times of 5, 7. 5 and 10 days provided loading rates

of 1. 35 - 0. 63 kg COD/m3_day and 1 . 36 - 0. 67 kg TS/m3_day. Removals

between inlet and outlet averaged 71% and were insensitive to loading

rate. T otal solids accumulation rates of 40-50% TS input rate suggests

that anaerobic tank design should be based on solids accumulation rate

and cleaning frequency.

The stone media trickling filter was loaded at approximately 0 . 61 kg

COD/m3-day. Aeration periods of 1, 2 and 3 days and hydraulic loads of

2. 8, 1 0 . 1 and 1 8 . 2 m3/m2_day were studied to determine their influence on treatment efficiency. Multiple regression analysis indicated that

the longer residence times and higher recycle rates improved treatment

efficiency. Removals varied with the mee.sured parameters but ranged

from 42-66% for COD. Design alterations to allow the final discharge tu be taken from the b ottom of the filter, after settling, would increase aerobic treatment efficiency above 75't� COD removal .

P rediction of treatment efficiencies beyc'nd the monitored operating conditions suggested that only margillal improvements could be made.

The TS accumulation rate in the aerobic T,hase was approximately 13% of

the TS input rate or 5G�� of the BaD removal rate.

Overal l plant treatment effi ciencies of 80-89% were obtained . Lemovals

in excess of 92% coc;ld be achieved with minor design alterations .

Maintenance and opel'ational requirements were minimal . The only problem

with the sys tem wa� an average 15 fold in�rease in N03-N and 4 fold

increase in DIP under conditions for optimum removal of the o ther

parameters . Interm�ttent land disp osal could reduce this p roblem.

Treatment c omparison between similar laboratory plar.ts , and between

laboratory and f ield plants which varied by a scale factor of 56, suggests that identically designed p lants would give a similar

performance and that there is little scale effect. Increasing tr._e

scale only improved treatment efficiencies under unetable aerobic

conditions, i . e . , high recycle rates and low resideLce times .

Increasing scale gave some d ecrease in maintenance and operational

problems .

Design of a full scale plant, based on daily p ollution loads froffi a 250 cow dairy shed , suggests that the system is a viab le: p roposition.

- Mr I.R. Hlcghes, S ta tisti c ian, Dairy Research I n s ti';u t e; for his

assistanc e i n s ta t istical analysis.

- S taff of the Printery and P h o t o graphic Departmentsr Massey U niversi ty;

for the i r assistan c e in produ cing thig thesis.

- Mobil Oil New Zealand L td . ; for the grant of $1, 000 to assis t in the

c ons tru c t ion of the field treatment p lant.

CHAPTER

CHAPTER

C O N T ENTS

1 . INTRODUCTION

1 : 1 ) The New Zealand Dairy I ndustry

1 : 2) Dairy Effluent Treatment

2. DAIRY SHED EFFLUENT TREATMENT - A REVIEW

2: 1 ) Effluent P roduction at the Dairy Shed

2! 2 ) Treatment 1I1ethods and the Law

2:2 . 1 ) T�e Water and Soil Conservation Act

2:2 . 2 )

2:2 . 3 )

Dai ry Regulations

N�tional Surveys of Dairy Shed Effluent Treatment

2:3) Land Disposal

2: 3. 1 ) IntroductioY1

2: 3. 2) resign and Loading Rates

2:3. 2, 1 ) Hydr&ulic Loads

2:3.2,2) Solid Loads

2: 3. 2, 3 ) Nutrj.ent Loads

2:3.3 ) Treatment Efficiency

2: 3.3, 1 ) Runoff and Infiltration Qual ity

2:3. 3 , 2 ) Soil Quality

2:3.4) Plant Growth Responses

2:3.5) Animal Health

2: 3.5, 1 ) Disease T ransmission

2:3.5,2) Metabolic Disorders

2:3. 6 ) Pretreatment for Land Disp osal

2 : 3 .7) Economics of Land Disposal

2:4 ) Anaerobic Treatment

2:4. 1 ) Introduction

2:4. 2 ) Principles of Anaerobic T reatment 2:4.2, 1 ) Biochemical Reactions

2:4;2 , 2) Environmental Requirements 2:4. 3) Anaerobic Lagoons

2:4.3, 1 ) Loading Rates

2

2

6

7

7 7

1 0

1 0

1 2

1 2

1 2

1 2

1 3

1 3

1 3

1 3

1 5

1 5

1 5

1 5

1 5

1 6

1 6

1 7

1 7

1 8

1 8

1 8

1 8

20

Page

2:4.3,2) Lagoon Op eration 21

2: 4. 3, 3) Treatmen t Eff ic::. ency 21

2:4.3,4) Solids A ccumulation and D isposal 22

2:4.4) Capp ed Anaerobic Digest ion 23

2:4.4,1) Loading Rates 23

2:4.4,2) Treatment Eff iciency and Ga s Production 24

2:4.4,3) Design and Development 24

2:5) A erobic Treatment

2:5.1) Introduction

2:5.2) Oxidation P onds

2:5.2,1) Design Considerations

2:5.2,2) Treatment Efficiency

2:5.3) Aerated Lago ons

2:5.4) Tri ck l ing F il ters

2:5.4,1)

2:5.4,2)

2:5.4,3)

2:5.4,4)

2:5.4,5)

2:5.4,6)

Introduction

Design Considerations

Temperature Effe cts

Kinetics and Op timizat ion

Nu trient Removal

Trickling Fil ters in Lives tock Waste Treatment

2:5.5) Rotating Biological Discs

2:5.6) Oxidation Ditches

2:5.6,1) Design of Oxidation D i tches

2:5.6,2) Operation of Ox idation Ditches

2:5.7) Comp os ting

2:5.8) Odour Control

2:6) Physi cal and Chemical Treatment

2:6.1) Solid/Liquid Separation

2:6.1,1) Sedimentation

2:6.1,2) Sol id/Liquid Separat ors

2: 6.2) Chemical Trea tment

2:7) Waste Recycle

CHAPTER 3. PROJECT DEVELOPMENT

3:1) Introduction

25

25

25

25

26

27

27

27

28

31

32

34

34

36

36

36

37

37

38

38

38

38

39

39

39

41

42

3 : 2 ) Biological Treatment

3 : 3 ) Imp l e�entation of C oncep ts

CHAPTER 4. PLANT DEVELOPMENT - INITIAL SS:UDIES

4.1 ) Sel e ct i on of Effluent Sourc e

4,2 ) Single Tank T reatment

4 : 2 . 1 ) I ntroduc tion

4: 2 . 2 ) Ini tial P i l o t P lant

4 : 2 . 2,1) Design and Construc tion

42

43

45

46

46

46

46

46

4 : 2 . 2,1 ) P lant Op erati on 48

4: 2 . 3) A Glass C o lumn Fil ter 48

4: 2.4) C onclusi o ns from the Single Tank T reatment 49 P l ants

4. 3 ) Twin �ank T reatment

4: 3. 1 ) =nt r o du c t i on

4: 3 . 2 ) j)esign and C onst ru c t i on

4 : 3 . 3) Op erat ion of the Twin Tank P lant

4: 3 .4 ) C onclus i o ns f rom the Twin Tank Treatment System

CHAPTER 5. PLANT DEVELOP NENT - FINAL DESIGN

5: 1) Laborat ory P lant C onstructi on

5:2 ) Fie l d P lant Construc tion

CHAPTER 6. EXPERIMENTAL METHODS

6:1) Samp l e C ollection

6 . 1 . 1 ) Raw Was t e

6 : 1. 1 , 1 ) Manual Col lec t i on

6 : 1. 1 , 2 ) Au tomatic Coll e c t i on

6 .1 . 2 ) Treated Effluent

6:2) Samp l e Analysis

6 : 2 . 1 ) Timing of Analyses

6:2.2) A nalytical P arameters and Ne thods

6 : 2 . 2, 1 )

6:2 .2,2)

T otal Samp le Analysis

Sub-Samp le Analysis

6:3) Other Re cords

49

49

49

51

54

57

58

58

64

6 5

6 5

6 5

6 5

67

69

69

69

69

70

71

I�:HAPTER 7 . EXPERIMENTAL DESIGN 73

7 :1) Initial Studies

7 : 2) Main Trials

7: 2 . 1 ) Operational Procedure

7 : 2 . 2) Data Analysis

74

74

74

76

CHAPTER 8 . RESULTS AND DISCUSSION 79

CHAPTER

8: 1 ) Collected Data 80

8 : 2 ) Characteristics o f Dairy Shed Effluent

8: 2 . 1) Ivleasured Characteristi·::s

80 00 82

82

8: 2. 2) Pollution Loads from Dairy Shed Effluent

8:2 . 3 ) Correlation of Pollution Parameters

8: 3 ) Anaerobic Treatment Phase 82

8:3. 1 ) Anaerobic Loading Rates 85

8:3.2) Anaerobic Treatment Efficiencies 85

8 : 3 . 3) Anaerobic Solid Accumulation and Disposal 88 8:3.4) Comparison of the Laboratory and Field Plants 92

8: 4 ) Aerobic Treatment Phase 9 3

93

9 3

8:4.1) Aerobic Loading Rates

8: 4. 2 ) Aerobic Treatment Results

8:4. 2 , 1 ) Introduction 93

8: 4 . 2 , 2 ) Regression Equations and Contour 96 Diagrams

8: 4.2,3) Discussion of Aerobic 'llre.:J.tment Resul ts 99

8: 4 . 2 , 4) Anaerobic Influence on Ae�obic 1 1 3 Treatment

8: 4.2,5 ) Prediction of Treatment Efficiencies 1 1 5

8:4.3) Solids Accumulation in the Aerobic Tank 1 1 5

8:4.4) Treatment Plant Comparisons

8 : 5) Correlation of BOD and COD

1 20

125

9. GENERAL DISCUSSION 1 2 6

9: 1 ) Total Plant Treatment Efficiencies 1 27

9 : 2) Nitrogen Analysis 130 9: 2. 1 ) Nitrate Nitrogen 130

CHAPTER

9:2 . 2) knmoniacal Nitrogen

9:2.3) Kjeldahl Nitrogen

9 : 2 . 4) To tal Nitrogen

130 1 32

1 32

9:3) Phosphorus Analysis 1 32

1 36 9: 4) Pollution Loads on Natural vlaters

9:5) Plant Operation 1 36

1 0 .

9:5. 1 ) Loading and Daily Maintenance 136

9:5.2) Pump Performance Problems 136 9:5.3) Line Bl ockages through the Treatment Plants 1 38

9:5. 4) 20lids Cleaning 1 39

9:5.5) Plant Scale Effects on Operation 1 39

CONCLUSIONS 1 42

W. 1 ) Dairy Shed Effluent 1 43

1 0 . 2) Anaerobic Treatment 143

1 c;. 3) Aerobic Treatment 1 44

10.4) Total Plant Operation 1 44

CHAPTER 11, APPLIChTION OF ANAEROBIC 'l'REATMENT Mm T RICKLING 1 46 FILTER AERATION TO THE N. Z. DAIRY Il�UI�TRY

11.1) Design of a Full Scale Anaerobic/Ae�cbic 1 47 T reatment Plant

11.2) Performance and Operation of the Tr8£·.tlllent Plant 1 47

1'1,3) Capital and Operating Costs 1 50

CHAPTER 1 '.2. RECOMMENDATIONS 15 1

APP ENDIX I .

APP ENDIX I I.

APPENDIX Ill.

APPENDI X I V.

APPENDIX V.

APPENDIX VI.

A P P E N D ICE S

REPORTED CHARACT ERISTICS OF DAIRY SH�D EFFLUENT

DEVELOPNENT OF AN AlifAEROB:!.C/ AEROBI C TREATMENT P Lk1T

FOR DAIRY m{ED EFFLU�ifT

WORKING DRAWINGS FOR FIELD SCAL E TRE�TMENT PLANT

ROTARY T IPPING BUCKET - DESIGN AND OP ERATI ON

COLLECT ED DATA

LABORATORY P LANT DATA FRO>'! ANAEROBIC AND AEROBIC

SOLIDS REMOVAL

APPENDIX VII. MONTHLY VARIAT:::ONS IN DAIRY m{ED EFFLUENT

APPENDIX VIII. DESIGN OF AN Al�AEROBIC TANK AND TRICKLING FILTER

A ERATI ON SYSTEl'1 FOR A 250 C OV[ FACTOP.Y SUPPLY SHED.

BIB L lOG RAP H Y

LIS T o F T A B L E S

Page

1 : 1 Sta tistics for Factory Supply Dairy Farms in N.Z. 3

1 : 2 The Number of Factory &lpply Herds with more than 300 Cows 3

1 : 3 statistics for Town Supply Dairy Farms in N.Z. 4

2 : 1 Effluent Procuction per Cow-Day 8

2 : 2 A Summary of Fresh Water Classification in N.Z. 9

2 : 3 A Survey of Dairy Shed Effluent Treatment Systems 1 1

2 : 4 Runofl' Quali�y from Land Disposal A reas 1 4

2 : 5 Environmental Requireme�ts for Anaerobic Digestion 1 9

7 : 1 Experimental Design 75

7 : 2 C onfounding of Field P lant Treatments 77

7 : 3 Final Treatment Allocation to Experimental P lants and 78

T ime table of Analysis

8: 1 M eaned Data for Dairy Shed Effluent

8: 2 P ollution Loads from Dairy Shed Effluent

8: 3 C orrelation of Raw Waste Paramete�s

8:4 Anaerobic Tank Loadings 8: 5 Anaerobic Treatment in Laboratory P lants

8: 6 TS Balance for Laboratory P lant Anaerobic Tank

8: 7 VS Balance for Laboratory P lant Anaerobic Tank

8 : 8 Anaerobic T reatment Efficienc ies for the Field P lant

8: 9 Laboratory P lants - Dai ly Aerobic Loading Rates

8: 1 0 Treatment Combinations and Covariates for Aerobic

Regression Analysis

8: 1 1 Regression Equations for Aerobic Treatment Using

Laboratory Plant Data

81

83

84

86

87

90

9 1

94

95

97

98

....

8: 1 � Predicted Treatment Effic iencies for Aerobic Treatment 1 09

Using Laboratory P lant Data

8: 1 3 COD Concentrations through the Aerobic T reatment Phase 1 1 1

of the Laboratory P lants

8: 1 4 C omparison of BOD Concentrations at the Bottom of the 1 1 2

Filter and Final Discharge of Laboratory P lants

8: 15 DO Concentration (mg/l ) in the Laboratory P lalJ.t Discharge 1 1 4

8: 1 6 Solids Accumulation in the Laboratory Plant Aerobic Tanks 121

8: 1 7 Field P lant - Daily Aerobic Loading Rates 1 23

8: 1 8 Plant Comparisons for Aerobic Treaiment 1 24

9 : 1 Anaerobic/Aerobic Treatment Efficiencies 1 28

9 : 2 N03-H Discharge Concentrations Relative to Ae:..nobic 1 31

Treatment for Laboratory P lants

9: 3 TEN Removal for Laboratory P lants 1 33

9 : 4 Anaurobic/Aerobic Treatment Effect on Nitrogen 1 34

9 : 5 Anaerobic/Aerobic Treatment Effect on Phospho rus 1 35

9 : 6 P ollution Loads on Receiving Waters after Treatment 1 37

1 1 : 1 Daily and Annual P ollution Loads Di.scharged from an 149

Anaerobic/Aerobic Treatment Plant Receiving Effluent from a 250 Cow Factory Supply Dairy Shed

LIS T O F FI8-U R E S

Page

4: 1 Anaerobic Tank structure 50

4: 2 Schematic Di&.gram of Tr�ckling Filter Collecting Tray 53

6 : 1 Sampling P osHions 68

7 : 1 Experimental P rocedure per Setting 75

8: 1 Contour P lo t for COD OU�C Using Lab.)ratory P lant Data 1 00

8: 2 Contour P lot for P ercent COD Removal Using Laboratory 1 0 1

P lant Data

8: 3 Contour P lo t for BOD OU? Using Laboratory Plant Data 1 02

8: 4 C ontour P lot for TS OUT Using Laboratory P lant Data 1 03

8: 5 C ontour P lot for Percen� TS Removal Using Laboratory 1 04

P lant Data

8: 6 C ontour Plot for VS OUT Using Laboratory P lant Data 1 05

8: 7 C ontour P lot for Percen·� VS Removal Using Laboratory 1 06

P lant Data

8: 8 C ontour P lo t to P redict COD OUT 1 1 6

8: 9 Contour Plot to Predict BOD O UT 1 1 7

8: 1 0 Contour P lot to P redict TS OUT 1 1 8

8: 1 1 Contour Plot to predict VS OUT 11 9

8: 1 2 Settl ing Curve for Aerobic Sludge Removed from 1 22

1 1 : 1

Laboratory P lants

Anaerobic/Aerobic Effluent Treatment P lant for a 250

Cow Factory Supply Dairy Farm 1 48

=L-,I�S;......=.. T _ _ ....;;O--=-F_..zP--=-L A T E S

P age

4 : 1 Single 1 95 litre Tank and Trickling iilter Unit 47

4: 2 Loading and Recycle Pump for the Single Tank Unit 47

4 : 3 Twin T ank Anaerobic/Aerobic Treatment with the ?erspex 52

Trickling Filter Mounted above the Aerobic Tank

4 : 4 Filamentous Growth from the Bottom of the Trickling Filter 55

4 : 5 Close-up of the Filamentous Growth 55

5 : 1 General Arrangement of Laboratory Plant 59

5 : 2 Anaerobic Tank, Control Box and Metering Tanks of Field 60

Plant

5 : 3 Anaerobic Tank and Trickling Filter Arrangement for F ield 60

Plant

5 : 4 Trickling Filter Support Structure for Field Plant 6 1

5: 5 Rotary Tipping Bucket Distributor on Top of the Field 6 1

Plant Trickling Filter

5:6 Field Plant Trickling Filter , Aerobic Tank, Recycle Pump 62

Housing and Motor Control

6: 1 Effluent Collecter Showing Collec ting Channels and the 66

Collecting Tank

6: 2 Mono CP 25 Loading Pump T:;:-ansf'erring Effluent from the 66

Collec ting Tank to the Input Metering Tank

9 : 1 Visual Appraisal of Dairy Shed Effluent during Treatment 129

9: 2 Solid Crust on }<'ield Plant Anaerobic Tank 1 40

A B B REV I A T I O N S

BOD biochemical oxygen demand Mg magnesillIl

C = carbon ml millilitre

°c degrees Celsius MLVS S = mixed liquor volatil e

Ca calcium

CH4 = me thane

CMD coefficient of multiple

CO2

COD

DIP

DKN

DM

D O

DOP

determina ticm

carbon dioxi de

= chemical oxygen demand

= dissolve d inorganic phosphate

= dissolved Kj eldah l nitrogen

= dry matter

= dissolved oxygen

= dissolved organi c phosphate

F/M food to mi cro organism ratio

g gram

h = hour

ha = ll ec tare

I . D . internal diameter

K potassium

kg = kilogram

kW kilowatt

1 = li tre

m L1 e tre

max. maximum

mg mill igram

susp ende d solids

mm = mill imetre

mV millivo lt

N nitrogen

Na = sodium

Na202 sodium peroxide

NaOH = sodium hydroxide

NH4-N = ammon iacal ni trogen

N03-N = nitrate nitrogen

oxygen

= phosphorus

ppm = parts per million

RBD = rotating biological iisc

rpm = revolutions per minu te

s = second

S.T.P. = standard temp erature and pressure

TDN = total dissolved nitrogen

TDP = to tal dissolved pho sphate

TEl'JIP = temp erature

TKN total Kjeldahl n i trogen

TN = to tal nitrogen

TP = total phosphate

TPN = total p articulate ni trogen

TPP total particulate ptosphate

TS

VF A

= total solids

= volatile fatty acids

vs

yr

= volatile solids

year