Designing laboratory and field studies of biomass cookstove

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DESIGNING, LABORATORY AND FIELD STUDIES OF BIOMASS COOKSTOVE

AMIT RANJAN VERMA

CENTRE FOR RURAL DEVELOPMENT & TECHNOLOGY INDIAN INSTITUTE OF TECHNOLOGY, DELHI

FEBRUARY 2021

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©Indian Institute of Technology Delhi (IITD), New Delhi, 2021

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DESIGNING, LABORATORY AND FIELD STUDIES OF BIOMASS COOKSTOVE

by

AMIT RANJAN VERMA

Centre for Rural Development & Technology

Submitted

In fulfilment of the requirements of the degree of

Doctor of Philosophy

to the

Indian Institute of Technology Delhi

FEBRUARY 2021

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Dedicated to …..

My Beloved parents

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CERTIFICATE

This is to certify that the thesis entitled “Designing, Laboratory and Field Studies of Biomass Cookstove” being submitted by Mr. Amit Ranjan Verma to the Indian Institute of Technology Delhi for the award of the degree of Doctor of Philosophy is a record of bonafide research work carried out by him. He has worked under our guidance and supervision, and has fulfilled the requirements for the submission of this thesis, which has attained the standard required for a Ph.D.

degree of this Institute.

The results represented in this thesis have not been submitted elsewhere for the award of any degree or diploma.

Prof. Rajendra Prasad Honorary Professor

Centre for Rural Development and Technology

Indian Institute of Technology Delhi Hauz Khas, New Delhi–110016, India

Prof. Virendra K. Vijay Professor and Head

Centre for Rural Development and Technology

Indian Institute of Technology Delhi Hauz Khas, New Delhi–110016, India

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ACKNOWLEDGEMENTS

The writing of this thesis has been one of the most significant academics challenges I have ever had to face. Without the support, patience and guidance of the following people, this study would not have been completed. I would like to express my sincere gratitude for the immense amount of encouragement. I have received from both of my research supervisors, Prof. Rajendra Prasad and Prof. Virendra Kumar Vijay. Their wisdom, knowledge and commitment to the highest standards inspired and motivated me.

I am highly obliged to the members of Student Research Committee (SRC), Prof. S. N.Naik (Chairman), Prof. K. K. Pant (External Expert) and Prof. Satyawati Sharma (Internal Expert), who gave me technical suggestions and positive way of direction to my research work.

I am grateful to Dr. Ram Chandra for his valuable suggestions, encouragement and inspiring support during this work.

My special thanks to Mr. Ratneah Tiwar, my colleague at Biomass cookstoves laboratory

(CRDT) for helping me conduction laboratory and as well as field testing of biomass cookstoves.

My hearty thanks to Ms. Risha Mal, my colleague at Biomass cookstoves laboratory

(CRDT) for helping me in developing of TEG cookstove. She has carried out the TEG integration work in TEG cookstove (Mal, 2017).

I express my humble thanks to my staff mates Mr. Krishna Singh, Mr. Ramesh Yadava Mr.

Birender Singh and Mr. Pratap Singh for their continuous support and help to accomplish the goals.

I am also grateful, to all those who in some way or other bestowed generosity upon me regarding this study.

Last but not the least, I would like to thank my mother & father for educating me with aspects from both arts and sciences, for unconditional support and encouragement to pursue my interests, for

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listening to my complaints and frustrations, and for believing in me.

Date: Amit Ranjan Verma

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ABSTRACT

This research work starts with an evaluation of a general methodology for designing and development of improved biomass cookstoves. A natural draft, a forced draft, and a self–sustaining power generating Thermo-Electric Generating (TEG) biomass cookstoves have been developed by following the general methodology of designing of biomass cookstoves. The performance of these cookstoves were measured under laboratory conditions using Bureau of Indian Standards (BIS) protocol and all of them met the BIS standards.

Further field testing of two of the developed cookstoves (out of five), along with other available commercially biomass cookstoves were done in the field using Uncontrolled Cooking Test (UCT) protocol. Most of the improved stoves had significant fuel and emissions reductions relative to the traditional cookstove. Five (2 developed and 3 commercially available) of the cookstoves models saved more than 30% of fuel compared to the traditional cookstove. The best performing cookstove, in terms of fuel efficiency and emissions performance, was a model using processed fuel (pellets) and a fan, which assisted in supply of controlled amount of air for the combustion process. The Forced-Draft TEG stove performed quite well with high Modified Combustion Efficiency (MCE=Molar ratio of (CO2/(CO2+CO)) (95 - 96 %) and relatively low emissions of both PM2.5 and CO, reducing particulate matter and CO by 84 % and 71 % respectively as compared to Traditional Chulha. In Madhya Pradesh the developed forced draft medium Stove performed well compared to Bihar states with relatively low emissions of both PM2.5 and CO reducing particulate matter and CO by 62 % and 75 % respectively as compared to Traditional Chulha.

Overall, the results show that many of the cookstoves provide substantial performance improvements relative to the traditional cookstove, suggesting that user adoption should play a key role in deciding which cookstove models are ultimately promoted.

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Comparisons of laboratory and field performance results indicate that the general trends in fuel efficiency were somewhat consistent between the lab and the field, but emissions were much higher in the field tests than the laboratory tests.

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शोध- सार

यह शोध कायय बेहतर चूल्हे (कुकस्टोव) के डिजाइन और डवकास के डिए एक सामान्य पद्धडत के मूल्याांकन के साथ शुरू होता है। एक नेचुरि ड्राफ्ट , एक फोस्िय ड्राफ्ट, , और एक आत्मडनर्यर शडि उत्पन्न करने वािे थमोइिेडरिक जनरेटटग (टीईजी) चूल्हों को चूल्हे के डिजाइन की सामान्य पद्धडत का पािन करके डवकडसत ककया गया है। इन चूल्हों का मूल्याांकन र्ारतीय मानक ब्यूरो (बीआईएस) के प्रोटोकॉि का उपयोग कर प्रयोगशािा की डस्थडतयों

के तहत मापा गया था और वे सर्ी बीआईएस मानकों पर खरे उतरे।

इसके बाद अडनयांडित खाना पकाने के टेस्ट (यूसीटी) प्रोटोकॉि का उपयोग करके दो डवकडसत चूल्हों (पाांच में से

दो) के साथ-साथ अन्य व्यावसाडयक रूप से उपिब्ध चूल्हों का मूल्याांकन क्षेि में कया गया था। अडधकाांश उन्नत स्टोवों में पारांपररक चूल्हों के सापेक्ष ईंधन और उत्सजयन में कमी महत्वपूर्य आई थी। पाांच चूल्हों के मॉिि (2 डवकडसत और 3 वाडर्डययक रूप से उपिब्ध) पारांपररक चूल्हे की तुिना में 30% से अडधक ईंधन बचाया। ईंधन दक्षता और उत्सजयन प्रदशयन के मामिे में सबसे अच्छा प्रदशयन करने वािा चूल्हा, सांसाडधत ईंधन (पेिेट) का

उपयोग करने वािा मॉिि था, जो दहन प्रकिया के डिए डनयांडित मािा में हवा की आपूर्तत में सहायता करता

था।

फोसयि-ड्राफ्ट टीईजी चूल्हे की उच्च सांशोडधत दहन क्षमता 95 - 9 6 % थी, और पारांपररक चुिा की तुिना में

पीएम 2.5 और सीओ िमशः 84% और 71% अपेक्षाकृत कम उत्सजयन थे । मध्य प्रदेश में फोस्िय ड्राफ्ट माध्यम स्टोव ने डबहार राययों की तुिना में अच्छा प्रदशयन ककया, डजसमें पीएम 2.5 और सीओ दोनों पारांपररक चुल्हा

की तुिना में अपेक्षाकृत 62% और 75% िमशः कम उत्सजयन थे ।

कुि डमिाकर, पररर्ाम कदखाते हैं कक कई चूल्हे पारांपररक चूल्हे की तुिना में अच्छा प्रदशयन करते हैं, यह डनर्यय

िेने में महत्वपूर्य र्ूडमका डनर्ानी चाडहए कक कक उपयोगकताय आडखरकार कौन से चूल्हे को िे।

प्रयोगशािा और क्षेि के प्रदशयन के पररर्ामों की तुिना से सांकेत डमिता है कक प्रयोगशािा परीक्षर् के मुकाबिे

ईंधन दक्षता में सामान्य रुझान कुछ हद तक सांगत थे, िेककन प्रयोगशािा परीक्षर्ों के मुकाबिे क्षेि परीक्षर् में

उत्सजयन बहुत अडधक था।

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LIST OF FIGURES

Figure 1.1 Percentage of Indian rural (A) and urban (B) households using various

sources of household energy (Census 2011). 5

Figure 1.2 A. Greenway Jumbo, B. Environfit C. Supernova cookstoves. 8

Figure 1.3 TLUD cookstoves; A.Servals B. Champion 8

Figure 1.4 A Philips, B. Mimi Moto, C. TERI SPT 0610. 9

Figure 1.5 A. BioLite Home Stove, B.TERI Annapurna. 10

Figure 2.1 Different stage of wood combustion 18

Figure. 2.2 Five stages of drying curve 19

Figure 2.3 a. Mode of conductive; b. convective; and c.radiative heat transfer in a

cookstove 23

Figure 2.4 Stoves with chimney - A) Three pan Astra ole developed at IISc, B)

Daxustove developed in China 29

Figure 2.5 Some metal stoves - A) Priyagni B) Harsha 30

Figure 2.6 Philips wood stove - in-situ combustion stove 31 Figure 3.1 Iterative design methodology of cookstove modification 54

Figure 3.2 Cookstove testing setup under lab conditions 56

Figure 3.3 CHN elemental analyzer 61

Figure 3.4 A Traditional Indian cookstove 73

Figure 3.4 B Traditional cookstove simulated in the lab with 6 bricks 73

Figure 3.5 Drawing of ND-D cookstove 75

Figure 3.6 Performance result of cookstove with different burning rate (kg/h) 84 Figure 3.7 Emissions result of cookstove with different burning rate (kg/h) 84 Figure 3.8 Performance result of cookstove with different grate height (cm) 86 Figure 3.9 Emissions result of cookstove with different grate height (cm) 87 Figure 3.10 Performance result of cookstove with different pan support height 89 Figure 3.11 Emissions result of cookstove with different pan support height 89

Figure 3.12 Modifications made in ND-D cookstove 91

Figure 3.13 Experimental setup for measurement of volumetric flow rate (Q) of

blower fan 94

Figure 3.14 Air flow area of fan 95

Figure 3.15 Air flow pattern in prototype design 97

Figure 3.16 Drawing of inner structure FD-D cookstove 99

Figure 3.17 Performance result of FD-D cookstove with different burning rate

(kg/h). 101

Figure 3.18 Emissions result of FD-D cookstove with different burning rate (kg/h). 101 Figure 3.19 Performance result of FD-D cookstove with different fan power (W). 102 Figure 3.20 Emissions result of FD-D cookstove with different fan power (W). 103 Figure 3.21 Performance result of FD-D cookstove with different pan support height

(cm). 104

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Figure 3.22 Emissions result of FD-D cookstove with different pan support height

(cm). 104

Figure 3.23 Modifications made in FD-D cookstove 105

Figure 3.24 Drawing of FD-M cookstove 106

Figure 3.25 Performance result of FD-M cookstove with different burning rate

(kg/h) 107

Figure 3.26 Emissions result of FD-M cookstove with different burning rate (kg/h) 108 Figure 3.27 Performance result of FD-M cookstove with different fan power (W). 109 Figure 3.28 Emissions result of FD-M cookstove with different fan power (W) 109

Figure 3.29 Drawing of FD-I cookstove. 111

Figure 3.30 Performance result of FD-I cookstove with different burning rate (kg/h) 113 Figure 3.31 Emissions result of FD-I cookstove with different burning rate (kg/h) 113 Figure 3.32 Performance result of FD-I cookstove with different fan power (W). 114 Figure 3.33 Emissions result of FD-I cookstove with different fan power (W). 115 Figure 3.34 Model to simulate the IMPMUD stove in metal and fitted with the TEG

module 116

Figure 3.35 Front and rear view of FD- TEG cookstove filled with TEG module

assembly 117

Figure 3.36 Inner combustion chamber 118

Figure 3.37 A. Outer cookstove body, B. Extended outer jacket, C. Air jacket, D.

Pan support, E. TEG assembly and F. Assembly of components into cookstove

118

Figure 3.38 Drawing of TEG module 119

Figure 3.39 Drawing of cold side plate 119

Figure 3.40 Drawing of hot side plate 120

Figure 3.41 Drawing of TEG assembly 120

Figure 3.42 Drawing of FD-TEG cookstove 121

Figure 4.1 The thermal efficiency of developed biomass cookstoves 125 Figure 4.2 The power output of all developed biomass cookstoves 127 Figure 4.3 Emissions performance of all developed biomass cookstoves 128 Figure 4.4 The thermal efficiency of selected commercial cookstoves 130 Figure 4.5 The power output of selected commercial cookstoves 131 Figure 4.6 Emissions performance of selected commercial cookstoves 132 Figure 5.1 Map of Utter Pradesh with location of Fatehpur District (left) and

project site location in Fatehpur District of Uttar Pradesh 137

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Figure 5.2 Map of West Bengal with location of Howrah District (left) and the

project site location in Howrah District of West Bengal. 138 Figure 5.3 Map of Purnia District highlighting the project site locations Bihar 139 Figure 5.4 a Map of Jagadsinghpur District highlighting the project site locations in

Odisha 140

Figure 5.4 b Map of Mayurbhanj District highlighting the project site locations in

Odisha 140

Figure 5.5 Map of Chhindwara District highlighting the project site locations in

Madhya Pradesh. 141

Figure 5.6 Emissions sampling setup for a traditional cookstove in Uttar Pradesh

project site 147

Figure 5.7 A typical picture of traditional cookstoves in Uttar Pradesh (left) and

West Bengal. 149

Figure 5.8 Mean specific energy consumptions of states A. Uttar Pradesh, B. West

Bengal, D. Bihar, E. Madhya Pradesh, E. Odisha 166 Figure 5.9 Mean specific fuel consumption of states A. Uttar Pradesh, B. West

Bengal, D. Bihar, E. Madhya Pradesh, E. Odisha 168 Figure 5.10 Fire power of biomass cookstoves tested at A. Uttar Pradesh, B. West

Bengal, D. Bihar, E. Madhya Pradesh, E. Odisha states 170 Figure 5.11 Cooking time of biomass cookstoves tested at A. Uttar Pradesh,

B. West Bengal 171

Figure 5.12 Mean modified combustion efficiency of states A. Uttar Pradesh, B.

West Bengal, D. Bihar, E. Madhya Pradesh, E. Odisha. 174 Figure 5.13 Emission rates of biomass cookstoves at Uttar Pradesh 178 Figure 5.14 Emission rates of biomass cookstoves at West Bengal 179 Figure 5.15 Emission rates of biomass cookstoves at Bihar 180 Figure 5.16 Emission rates of biomass cookstoves at Madhya Pradesh 181 Figure 5.17 Shows emission rates of biomass cookstoves at Odisha 182 Figure 6.1 A. Fire power of stoves tested in laboratory and in field

B. Ratio of the Fire power in Laboratory and in Field

186

Figure 6.2 A. Specific fuel consumption of stoves in laboratory and in field B. Ratio of specific fuel consumption in the field and in the laboratory

189 Figure 6.3 Modified combustion efficiency of stoves in laboratory and in field 190 Figure 6.4 A. CO emissions rates of biomass cookstoves tested in laboratory and in

the field

B. Ratio of CO emissions rate in the field and in the laboratory

191

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Figure 6.5 A. PM2.5 emissions rates of biomass cookstoves tested in laboratory and in the field

B. Ratio PM2.5 rate in the field and in the laboratory

192

Figure 6.6 Specific time consumption (min/kg) of stoves in laboratory and in field 193 Figure 6.7 Ratio specific time consumption in the field and in the laboratory 194 Figure 6.8 Normalized specific time consumption (min/kg of water boiled) in the

laboratory in and in the field 194

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LIST OF TABLES

S. No Title Page No.

Table 2.1 Criteria used for dimensioning the fuel loading opening 26-27 Table 2.2 Analysis of cookstoves developed by various researchers 31-39 Table 2.3 Summary of field testing conducted in the past by various researches. 46-50

Table 3.1 List of equipment 55

Table 3.2 Results of proximate analysis of wood, pellet and charcoal 60 Table 3.3 Results of C:H:N analysis of eucalypti wood, wood char and pellets used

for cookstove testing. 62

Table 3.4 Result of calorific value (higher heating value) of wood, pellet and

charcoal fuels 63

Table 3.5 Systematic and random uncertainties in variables used in BIS protocol 72 Table 3.6 Benchmarking study on traditional biomass cookstove 74

Table 3.7 Dimensions of ND-D cookstove 76

Table 3.8 BIS permitted limits for forced and natural draft cookstoves 76

Table 3.9 Performance evaluation of ND-Dcookstove 77

Table 3.10 Conclusion from theoretical design 82

Table 3.11 Performance result of ND-D cookstove with different burning rate 83 Table 3.12 Performance result of ND-D cookstove with different grate height (cm) 86 Table 3.13 Performance result of ND-D cookstove with different pan support height 88 Table 3.14 Dimension of deign parameters of FD-D cookstove 98 Table 3.15 Preliminary performance tests result of FD-D prototype cookstove 99 Table 3.16 Performance result of FD-D cookstove with different burning rate 100 Table 3.17 Performance result of FD-D cookstove with different fan power (W) 102 Table 3.18 Performance result of FD-D cookstove with different pan support height

(cm) 103

Table 3.19 Dimension of deign parameters of FD-M cookstove 106 Table 3.20 Performance result of FD-M biomass cookstove with different burning

rate (kg/h) 107

Table 3.21 Performance result of FD-M biomass cookstove with different fan power

(W) 108

Table 3.22 Dimension of FD-I cookstove 112

Table 3.23 Performance result of FD-I cookstove with different burning rate 112 Table 3.24 Performance result of FD-I cookstove with different fan power (W) 114

Table 3.25 Production strategy for IMPMUD cookstoves 122

Table 3.26 Production strategy for TEG cookstove 122

Table 4.1 The thermal efficiency of cookstoves 125

Table 4.2 BIS limits for forced and natural draft cookstoves 126 Table 4.3 Power output of cookstoves

Table 4.3. Power output of cookstoves

127

Table 4.4 Emissions performance of cookstoves 128

Table 4.5 Analysis of overall energy balance in cookstoves 129

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Table 4.6 The thermal efficiency of selected commercial cookstoves 130 Table 4.7 Power output of selected commercial cookstoves 131 Table 4.8 Emissions performance of selected commercial cookstoves 132 Table 5.1 Detailed specifications of traditional cookstoves 154-155 Table 5.2 Detailed specifications of developed biomass cookstoves 156 Table5.3 Detailed specifications of other cookstoves 157-158 Table 5.4 List of different local partner at different geographical locations 159 Table 5.5 Sample size table for cross-sectional study design adapted from 161 Table 5.6 Number of samples collected across location for each stove type 163-164 Table 6.1 Ratio of the fire power in laboratory and in field 187 Table 6.2 Specific fuel consumption (kg of fuel used/kg of cooking) 189 Table 6.3 Ratio of specific fuel consumption in the field and in the laboratory 189 Table 6.4 Ratio of CO emissions rate in the field and in the laboratory 191 Table 6.5 Ratio PM2.5 rate in the field and in the laboratory 192 Table 6.6 Specific time consumption (min/kg) of stoves in laboratory and in field 193 Table 6.7 Normalized specific time consumption (min/kg of water boiled) in the

laboratory in and in the field 194

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Nomenclature

Symbols and abbreviations

% = Percent

/ = Per

< = Lower than

> = Greater than

0 = Degree

0C = Degree celsius

A = Pre-exponential factor

A = Area

A/F = Air-to-fuel ratio

Acc = The cross sectional area of the combustion chamber ASTRA = Application of Science and Technology for Rural Areas

B = Heat of Combustion (heating value) of wood fuel BIS = Bureau of Indian Standards

BR = Bihar

C = Carbon

CAD = Computer Aided Design CCT = Controlled Cooking Test

CH4 = Methane

cm = Centimetre

CNG = Compressed Natural Gas CO = Carbon monoxide

CO2 = Carbon dioxide Conc. = Concentration

Cp = Heat capacity at constant pressure

d = Gap between the pan bottom and the top plate db = Dry basis

DC = Direct Current E = Activation energy FD-D = Forced Draft -Domestic

FD-I = Forced Draft -Institution FDM = Forced Draft Metal FD-M = Forced Draft- Medium

FDP = Forced Draft Pellet

FD-TEG = Forced Draft -Thermo Electric Genetor

g = Gram

GACC = Global Alliance for Clean Cookstoves

GIZ = Deutsche Gesellschaft fur Internationale Zusammenarbeit GJ = Gigajoule

h = Hour

H = Hydrogen

H2O = Water

Hcc1 = Height of combustion chamber occupied by the fuelbed where charcoal burns and the pyrolysis take place

Hcc2 = Height of combustion chamber occupied by the flames

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HH = Household

I = Current

ICS = Improved Cookstove Stove IIT = Indian Institute of Technology IMPMUD = Improved Mud

IQR = Interquartile range

ISO = International Organization for Standardization ITDG = Intermediate Technology Development Group

IWA = International Workshop Agreement K = Kelvin temperature

kg = Kilogram

kJ = Kilojoule

KPT = Kitchen Performance Test

kW = Kilowatt

kW-h = Kilowatt hour

L = Litre

LPG = Liquefied Petroleum Gas M = Mass of volatiles produced

m = Fuel burning rate (kg/h)

m = Meter

n = Numbers of air holes M Pa = Megapascal

m³ = Cubic metre MC = Moisture Content

MCE = Modified Combustion Efficiency mg = Milligram

MJ = Megajoule

MJd = Megajoules of energy delivered to the pot mm = Millimetre

MNES = Ministry of Non-Conventional Energy Sources MNRE = Ministry of New and Renewable Energy

MP = Madhya Pradesh

MW = Megawatt

ND-D = Natural Draft -Domestic

NPIC = National Program on Improved Chulha

O2 = Oxygen

OD = Odisha

P = Power

PEMS = Portable Emissions Measurement System PIC = Products of Incomplete Combustion

PM2.5 = Particulate matter less than 2.5 microns in diameter ppm = Parts per million

R = Ideal gas constant

R1 = Rocket 1

R2 = Rocket 2

rpm = Revolution per minute

Rspecific = Specific gas constant for dry air

s = Second

SA = Standard Adult SOx = Sulphur dioxides

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STP = Standard Temperature and Pressure St. Dev = Standard Deviation

CoV = Coefficient of Variation CE = Combustion Efficiency

t = Time

T = Absolute temperature TC = Traditional Chulha

TERI The Energy and Resources Institute TLUD = Top Lit Up Draft

TPM = Total Particulate Matter TPM stove = Two-Pot Mud Stove

UCT = Uncontrolled Cooking Test UN = United Nations

UP = Uttar Pradesh

V = Volume

v Velocity

V = Voltage

VITA = Volunteers in Technical Assistance W = Fan power

W = Watt

WB = West Bengal WBT = Water Boiling Test

WSG = Woodburning Stove Group

yr = Year

Greek symbols

ø = Diameter (cm) α = Fraction of mass α = Sharp edges

δ = Gap between the pan and the shield (cm) ε = Emissivity

η = Efficiency (%) λ = Excess air factor μ = Viscosity (Pa-s) ρ = Density (kg/m³)

σ = Stephan- Boltzman constant (W/m²K⁴) υ = Volatile fraction

φ = Equivalence ratio χ = Packing density

ω = Fire penetration rate (kJ/h)

ψ = Stoichiometric air required for complete combustion of fuel (m³ STP)

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Subscripts

c = Charcoal

cc = Combustion chamber des = Design

max = Maximum

n = Normal

d = Deliver

Designing laboratory and field studies of biomass cookstove

DESIGNING, LABORATORY AND FIELD STUDIES OF BIOMASS COOKSTOVE

AMIT RANJAN VERMA

CENTRE FOR RURAL DEVELOPMENT & TECHNOLOGY INDIAN INSTITUTE OF TECHNOLOGY, DELHI

FEBRUARY 2021

DESIGNING, LABORATORY AND FIELD STUDIES OF BIOMASS COOKSTOVE

by

AMIT RANJAN VERMA

Centre for Rural Development & Technology

Submitted

In fulfilment of the requirements of the degree of

to the

Indian Institute of Technology Delhi

FEBRUARY 2021

Dedicated to …..

My Beloved parents

CERTIFICATE

ACKNOWLEDGEMENTS

ABSTRACT

शोध- सार

TABLE OF CONTENTS

LIST OF FIGURES

LIST OF TABLES

Nomenclature

Symbols and abbreviations

Greek symbols

Subscripts