Hydrocarbons TechnologyCrude Oil Refining Summary Notes

Sources of Energy/Fuel/Petrochemicals

Coal Crude Oil Natural Gas

Biomass

Reservoirs 1136billion tonnes

(India 315)

1730billion barrels

(India 5.69)

198trillion m3

(India 1.49)

unlimited

Expected life based on current consumption, years

120 60 60 Long lasting

Major reservoirs located at USA, Russia, China, India,

Australlia

OPEC, Russia, USA

OPEC, Brazil, USA

Every where

Source: CO & NG :: World Oil & Gas Review.

World Crude Oil reserves

2017Rank Country Proved reserves of Crude

Oil(billion barrels)

Share of total

1. Venezuela^ 297.7 18.1%2. Saudi Arabia^ 265.9 16.2%3. Canada 173.2 10.5%4. Iran^ 157.3 9.6%5. Iraq^ 140.3 8.5%6. Kuwait^ 101.5 6.2%7. United Arab Emirates 97.8 5.9%8. Russia 80.0 4.9%

9. Libya^ 48.5 2.9%10. Nigeria^ 37.1 2.3%11. United States 31.8 1.9%12 China 24.4 1.5%22. India 5.65 0.3%

World total 1,644.5 100.0Total OPEC^ 1,200.8 73.0%

OPEC : Algeria, Angola, Ecuador, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, United Arab Emirates and Venezuela

2019: 1730 billon barrels

CO price vs Fuel Price

CO price, $/barrel Petrol, INR Diesel, INR

July 2017 48 65 60

July 2016 46 66 61

Feb 2015 47 60 52

July 2015 62 70 56

July 2014 113 78 53

2015 Demand in India

Diesel: 72 MMT (70% for transportation)

Petrol: 19 MMT (99.6% for transportation)

Crude Oil based Industries:

Exploration of Crude Oil (E&P Industries) Refining of Crude Oil (Petroleum Refineries) Chemical production hydrocarbons (Petrochemical Industries)

Upstream Industries

Oil companies used to be classified by sales as "supermajors" (Saudi Aramco, National Iranian Oil Company (NIOC), BP, Chevron, ExxonMobil, ConocoPhillips, Shell, Eni and Total, Crain, Schlum Berger ).

Top 10 largest world oil companies by reserves and production

Rank Company (Reserves)

Worldwide Liquids

Reserves (109 bbl)

Worldwide Natural Gas

Reserves (1012 ft3)

Total Reserves in Oil

Equivalent Barrels (109

bbl)

Company (Production)

Output (Millions

bbl/day)[1]

1 Saudi Aramco 260 254 303 Saudi

Aramco12.5

2 NIOC 138 948 300 NIOC 6.4

3 Qatar Petroleum 15 905 170 ExxonMobil 5.3

4 INOC 116 120 134 PetroChina 4.45 PDVSA 99 171 129 BP 4.1

6 ADNOC 92 199 126 Royal Dutch Shell

3.9

7 Pemex 102 56 111 Pemex 3.68 NNPC 36 184 68 Chevron 3.5

9 NOC 41 50 50Kuwait

Petroleum Corporation

3.2

10 Sonatrach 12 159 39 ADNOC 2.9National Iranian Oil Company (NIOC), Iraq National Oil Company (INOC)Petróleos de Venezuela, S.A. (PDVSA), Petroleum of VenezuelaAbu Dhabi National Oil Company, Nigerian National Petroleum Corporation (NNPC),

World’s refining capacity of crude oil: 104 million barrels per day in 2019

Refining capacity, million barrel/day: 2013: US 17.8, China 12.6, Russia 6. Japan 4.1, India 4.3

World’s Largest Refiners (Based on Total Refining Capacity)

S.No. Company Crude Capacity, barrels per calendar day (b/cd)*

1 ExxonMobil Corp. (USA) 5,783,000 2 Royal Dutch/Shell (NL/UK) 4,509,239 3 Sinopek (China) 3,971,000 4 BP (UK) 3,325,050 5 ConocoPhillips (USA) 2,778,200 6 Chevron Corp. (USA)** 2,755,600 7 PDVSA (Venezuela) 2,678,000 8 Valero Energy Corp. (USA) 2,616,500 9 CNPC (China) 2,615,000

10 Total (France) 2,451,106

World's Largest Oil Refineries (based on single lane)

Rank Company Location Crude Capacity, barrels per day

(b/d)1. Paraguana Refining Center Cardon/Judibana, Falcon,

Venezuela940,000

2. SK Corp. Ulsan, South Korea 817,0003. GS Caltex Corp. Yeosu, South Korea 750,0004. Reliance Petroleum Ltd. [merged

with RIL since 2009]Jamnagar, India 660,000

5. ExxonMobil Refining & Supply Co. Jurong/Pulau Ayer Chawan, Singapore

605,000

6. Reliance Industries Ltd. [RIL] Jamnagar, India 580,0007. S-Oil Corp. Onsan, South Korea 565,0008. ExxonMobil Refining & Supply Co. Baytown,** Texas, USA 560,5009. Saudi Arabian Oil Co. (Saudi

Aramco)Ras Tanura, Saudi Arabia 550,000

World's Largest Oil Refineries (based on location)

No. Name of refinery Location Barrels per day

1 Jamnagar Refinery (Reliance Industries) Jamnagar, India 1,240,000

2 Paraguana Refinery Complex (PDVSA) Punto Fijo, Falcón, Venezuela 940,000

3 SK Energy Ulsan Refinery (SK Energy) Ulsan, South Korea 850,000

4 Ruwais Refinery (Abu Dhabi National Oil Company) Ruwais, UAE 817,000

5 Yeosu Refinery (GS Caltex) Yeosu, South Jeolla, South Korea 730,000

6 Onsan Refinery (S-Oil) Ulsan, South Korea 669,000

7 Jurong Island Refinery (ExxonMobil) Jurong Island, Singapore 592,000

8 Port Arthur Refinery (Saudi Aramco) Port Arthur, Texas, United States 603,000

9 Baytown Refinery (ExxonMobil) Baytown, Texas, United States 560,500

10 Ras Tanura Refinery (Saudi Aramco) Ras Tanura, Saudi Arabia 550,000

11 Garyville Refinery (Marathon Petroleum) Garyville, Louisiana, United States 543,000

12 Baton Rouge Refinery (ExxonMobil) Baton Rouge, Louisiana, United States 502,500

13 Galveston Bay Refinery (Marathon Petroleum) Texas City, TX, United States 459,000

14 Abadan Refinery (NIOC) Abadan, Iran 450,000

15 Lake Charles Refinery (Citgo) Lake Charles, United States 425,000

http://www.arabianoilandgas.com/article-6235-worlds_10_largest_petrochemicals_companies/

World's 10 largest petrochemicals companies

1. BASF (Germany)Dow Chemical (USA)2. ExxonMobil Chemical (USA)3. LyondellBasell Industries (Netherlands)4. INEOS (UK)

5. Saudi Basic Industries Corporation (Saudi Arabia)6. Formosa Plastics Corporation (Taiwan)7. Sumitomo Chemical (Japan)8. DuPont (USA)9. Chevron Phillips (USA)

Reasons for India as a favourite location for New Refineries:

Location: Sea Coast and Land locations are appropriate for the transportation of crude oils as well as export of finished products

Manpower: Availability of skilled and economic manpower Market: Market is quite big from population point of view, expansion of

chemical industries and exponent significant increase in usage of vehicles

High rate of return/short pay-back-period Environmental regulations

Indian Refineries:

26 Refineries: 254 MMTPA

New Refineries: 121 MMTPA, Expansion: 50 MMTPA

For Upcoming refineries refer PPT.

India - 2017

Bongaigaon Refinery (IOC), Dhaligaon, Bongaigaon City - 783385, Western Assam, 2.35 MMTPA

Digboi Refinery (IOC), Upper Assam, India's oldest refinery, 0.62 MMTPA Guwahati Refinery (IOC), Noonmati, Guwahati Metro - 781001, 1.0

MMTPA Numaligarh Refinery, Golaghat district (out of town), Assam Barauni Refinery, 6 MMTPA (IOC) Essar Refinery (Essar Oil), 406,000 bbl/d (64,500 m3/d) Gujarat Refinery (IOC), Vadodara Jamnagar Refinery Reliance Industries, Jamnagar, 1,240,000 bbl/d

(197,000 m3/d) Panipat Refinery, 15 MMTPA (million metric tonnes per annum) Mangalore Refinery (MRPL), 199,000 bbl/d (31,600 m3/d) Bina (Bharat Oman Refinery Ltd.), 116,000 bbl/d (18,400 m3/d) Guru Gobind Singh Refinery, Bathinda with capacity of 9 MMTPA (million

metric tonne per annum). Haldia Refinery (IOC), 116,000 bbl/d (18,400 m3/d) Paradip Refinery (IOC), 303,000 bbl/d (48,200 m3/d) Mathura Refinery (IOC), 156,000 bbl/d (24,800 m3/d) Mumbai Refinery (HPCL), 107,000 bbl/d (17,000 m3/d) Mumbai Refinery Mahaul (BPCL), 135,000 bbl/d (21,500 m3/d) Visakhapatnam Refinery (HPCL), 150,000 bbl/d (24,000 m3/d) Tatipaka Refinery (ONGC), 1,600 bbl/d (250 m3/d) Yanam Refinery, Reliance Industries Yanam, Puduchery Amalpuram Refinery, Cairn Energy Amalapuram Kochi Refinery (BPCL), 190,000 bbl/d (30,000 m3/d)

Chennai Petroleum Corporation (IOC), Chennai, Tamil Nadu,[19] 185,000 bbl/d (29,400 m3/d)

Cuddalore Refinery (Nagarjuna Corporation), 125,000 bbl/d (19,900 m3/d)

Nagapattnam Refinery (CPCL), 20,000 bbl/d (3,200 m3/d)

Detection of Crude Oil or Locating Oil fields:1. Gravity and Magnetic methods:

Reservoirs

Gravity and Magnetic methods

The geophysicist uses physical phenomenon such as magnetic attraction, the pull of gravity, the speed of sound waves through different types of rocks, and the behavior of electric currents to determine the subsurface structure. Here we will discuss two of the more important exploration methods used by geophysicists; namely, gravity mapping and magnetic mapping. A sedimentary basin is normally underlain by igneous and/or metamorphic basement rocks.These basement rocks have two important properties that distinguish them from sedimentary rocks in the eyes of a geophysicist. (1) They are more magnetic than sedimentary rocks; and (2) They are more dense than sedimentary rocks. These two differences provide the basis for two very useful geophysical techniques; magnetic surveying and gravity surveying.

Gravity and Magnetic Profiles

The magnetic properties of basement rocks create distortions and anomalies in the earth’s magnetic field. The magnitude of these anomalies as measured at the surface, is proportional to the depth of burial of the basement rocks as shown in above figure.

2. The Seismic SurveyThe most accurate and widely used means of finding good drilling locations is the seismic survey. Seismic surveying involves sending sound waves down into the ground and recording the echoes that bounce back off the various sedimentary layers.The sound or shock waves are generated by; setting off small explosive charges just below the surface; hitting the ground with a heavy weight; or shaking the ground using large vibrator trucks. The echoes returning from the subsurface are detected by sensitive instruments called geophones which are strung out along the ground in a straight line. The geophones are connected by electrical cable to a recording system. The recording system precisely records, to the nearest one thousandth of a second on magnetic tape, the time ittakes for the echoes to return to the surface. By knowing the amount of time it takes for a sound wave to reach a certain layer and then bounce back to the surface, as well as the speed of sound through the rock layers in between, the geophysicist is able to determine the depth to that layer at that location. By determining the depth at a large number of points along the seismic line, the geophysicist is able to create a profile of the underground layers along the line.

3. Chemical Analysis

4. Remote sensing

5. Satellite imaging

Exploration of Crude Oil:1. Primary recovery: The high pressure of Oil and Gas causes the Natural

flow from earth crust.

2. Secondary Recovery: specialised pump like 360o are used for the secondary recovery. The water or Air or CO2 injections are also used.

3. Tertiary Recovery: Steam Injection or CO2 flooding methods are used for the tertiary recovery.

Oil Well

Petroleum or Crude Oil BasicsDefinition:“It is defined as a naturally occurring mixture consisting predominantly of hydrocarbon and /or of sulphur, Nitrogen and /or oxygen derivatives of hydrocarbons, which is removed from the earth in liquid state or is capable of being removed.”

Formation of crude oilA. Inorganic theoryB. Organic theory

A. Inorganic Theory1. CaC2 + 2H2O C2H2 + Ca(OH)2

Al4C3 + 12 H2O 3CH4 + 4Al(OH)3

Carbides present in earth’s crust.

2. H.C. vapours were present in the atmosphere (H.C. cloudes).

Favourable conditions: H.C. raining,H.C. adsorbed or entrapped in earths crust.

Above Theories are not acceptable due to.

Inorganic could not produce C12-C13 isotopes. Optical activity, not observed in In-org. Most organisms, like diatomic are found in petro.

B. Organic Theory

Petroleum was formed from remains of plants and animals died years ago and accumulated or ocean floors.

Sand, clay, lime, rock surface materials deposited on beds of oceans. Over in of years, sediments piled up to a great height (several thousand

meters). P&T increased in above. Sea animals’ bodies also deposited. Aerobic bacteria- attacked to O.M. Complex chemical transformation due to high T & P (piling increases it). Process stages: fats, amino acids, lipids-oils.

Different Types of Gases:

1. Associated gas:

Separate gas-cap over liquid phase CH4 with some amount of propane and butane.

2. Dissolved gas:

Presents in liquid H.C. in dissolved state depending upon ‘P’. As P decreases it separates out.

3. Natural gas liquids:

When gas taken out, heavy gas propane, butane, pentane condensed in earth’s crest.

4. Casing Head gas:

Gas escaped through oil well X-tree, N.G. with less CH4.

Composition of petroleum crude oil

Liquid: hydrocarbons, S, O, N-Compounds, Salts etc.

Gas: associated gas, dissolved gas, casing head gas Solid: metals, asphaltenes, resins

Hydrocarbons

C 84-86%

H 11-14%

S, N, O compounds – total up to 5%

(Middle East, Gulf 1-3%) (India, Indonesia, Nigeria 0.2-1%)

(1) Paraffin: CnH2n+2 Alkanes

C1, C2, C3 – GasesC4 to C16 – Liquid

C16 to C30 – SemisolidAbove C30 – Solid (Traces)

Large amount of isomers i,e

Paraffins are stable & above C30 oxidation prone Up to C3, Hydrates formation occurs i.e. CH4 7H2O, C2H6 7H2O etc. Molecular weight and specific gravity are high compared to

unsaturated paraffin of same carbon no. Molecular weight and specific gravity of paraffin are less than

Aromatic compounds. Pour point is high that causes difficulties in transportation.

(2) Unsaturates or Olefins or Alkenes : CnH2n

C1 to C4 – gas

C5 to C15 – liquidAbove C15 – solid

Open chain compounds

Ethylene, Isobutene (Cis and Trans)

Boiling point slightly lower than saturated compound for same

carbon number. Chemically active Polymerize Present in crude in very small amount (forms during catalytic

cracking)

(3) Alkynes or Acetylenes : CnH2n-2

Open chain with triple bond

Acetylene (HC CH), Ethyl acetylene (HC C – C2H5)

Boiling point and density are higher than Alkanes. Yield crystalline compounds with ammoniacal solution. Upon hydrogenation stable compounds.

(4) Diolefins : CnH2n-2

Double bond compounds.

Allene (H2C = C = CH2), Divinyl

Can be distinguished from acetylenes as they do not form salts with ammoniacal solution.

(5) Naphthenes : CnH2n

Isomeric (same formula) with olefins but properties are quite different.

Exhibits properties of saturated paraffins & unsaturated aromatics with properties lie between two above.

(6) Aromatics

Unsaturated. High boiling point, High pour point, High octane number, High

viscosity. Burn with red flame with much soot. Resist oxidation. Distillation cuts of crude oil( middle approximately 5%, Heavy high

concentration)

(7) Inorganic or Non-hydrocarbons (S, N, O, Metals, Salts)

Sulphur compounds:

Higher average molecular weight of crude oil higher the sulphur content.

Normally less than 5% sulphur is observed but in some cases it is higher.

Venezuela 5.25%

California 5.21%

Qaiyarah (Iraq) 7%

Rozal point 13.95% (Utah State, USA)

(Ankleshwar: 0.05%, Bombay high: 0.02%)

ρ = 0.0087 (S%)2 + 0.0607 (S%) + 0.7857 (at 20 deg C)

a) Thiols or Mercaptans ( -SH)

CH3SH ( Methane Thiol or Methyle Mercaptane)

CH3CH2SH ( Ethane Thiol or Ethyl Mercaptane)

Present in low boiling point fractions (< 200 deg C) Cause corroison, poisioning unpleasent plant and lab odour. Ethane thiol in air 0.02 can be sensed by nose. Thiols are used in LPG for leakage detaction. Stronger acids than alcohols, therefore low molecular weight thiols can

be removed by caustic solution from light gasolines. Hydroprocessing for other oil fractions.

b) Mono sulphides CH3SCH2CH3 (Methyl ethyl sulphide)

CH3SCH2CH3 (Methyl propyl sulphide)

c) Disulphides

CH3SSCH3 (Methyl Disulphide)

Present in very low concentration in crude oil because of secondary reaction between Thiols and air/free sulphur generates them.

d) Thiophenes

Very low concentration in crude oil. However, higher aromatic content crude have small amount of Thiophenes.

Nitrogen compounds

Nitrogen compounds present in crude is ranging from 1 to 10% of sulphur compounds.

Higher the average molecular weight of crude higher the nitrogen compounds.

Nitrogen presents in free form in natural gas.

a) Basic nitrogen compounds (titrable with perchloric acid)

Predominant in low boiling point fraction of crude oil.

b) Non-basic nitrogen compounds

Present in higher boiling point fractions of crude oil. Compounds formed especially in catalytic cracking are, Aniline,

Phenazines, Nitriles.

Effect of nitrogen compounds

Loss of catalytic activity. Colour instability of products. Gum formation.

Oxygen compounds

Traces 2% maximum

Oxygen compounds increase from lighter to heavy fractions.

Low and medium boiling point range: carboxylic acid.

Other oxygen compounds: aliphatic, acids, phenol.

- Metals

Vanadium up to 0.1%, Ni and Fe

Cause undesirable reactions during refining other metals, Al, Na, Cu, Ca, Mg, Mn, Co, etc.

- Asphaltenes

Black amorphous solids mainly present in residue of removal of distillate.

Molecular weight: 600 to 30,000.

Hydro carbon with S, N2 compounds.

Soluble in aromatics and CS2.

- ResinsRing structure containing O, S, and N groups.

Dark coloured, solids or semi-solids.

Low molecular weight than Asphaltenes 800-2000.

Percentages of resins are more than Asphaltenes.

Classification of crude oil

Based on colour of crude oil:

- Light brown, Brown, Brownish Black, Black

- Light Blue, Bluish Black, Black

Based on sulphur content:

Sweet Crude (low sulphur content), Sour Crude (high sulphur content)

Based on type of hydrocarbons:

Paraffinc base – Residue more than 5% paraffins.

Mixed or intermediate base – Residue 2 to 5% paraffins.

Naphthenic base or asphaltic base – Residue less than 2% paraffins.

Based on UOP characterization factor:

KUOP

Paraffinic 12.5 - 13

Naphthenic 11 – 12

Aromatics 9 – 11

KUOP = (Tb)1/3 / G

Where, Tb = average boiling point in deg R, at 1atm.

G = specific gravity at 15.56 C/15.56 C

KUOP = (Tb)1/3 / 0.827G, Tb in K

Temperature required to collect distillate 10, 30, 50, 70, 90% volume from ASTM distillation are averaged.

Based on Correlation Index:

Correlation index (C.I) = (48640/Tb + 473.7 G – 456.8)

Where, Tb = boiling point in K

G = specific gravity at 15.6 C/15.6 C

For Paraffins CI=0 and Aromatic CI=100

CI Dominated fraction

0 – 15 Paraffinic

15 – 50 Intermediate

>50 Aromatics

Based on Nelson complexity factor:

The factor defined based on primary distillation is taken base and complexity involve in other processing unit as relative cost and manpower can also be calculated.

Based on type of refinery: Indirect indication of crude oil quality

N.F

America 7 – 9

Europe 6

RIL 14

N.F. Crude Quality

2 - 5 Good quality crude

6 - 9 Intermediate

>9 Heavy or crude with high impurities

Removal of Salts from Crude Oil

1. Gravity Settling

Addition of water to dissolve salts followed by gravity settling. It was used during early years of refinery technologies but now it’s obsolete due to large storage required, long time of settling and emulsion formation.

2. Chemical de-salting: Addition of small amount of water in crude oil followed by addition

of 0.5-5% additives like soda ash, fatty acid salts, petroleum sulfonates etc. This promotes flocculation by acting as demulsifying agents.

Additives promotes flocculation that results in fast settling of salts.

3. Centrifugal de-salting

It is effective but cost involved is very high so it’s not used.

4. Electro de-salting Most widely used method. Electric potential in the range of 10000-20000 v is applied to the

continuous flow of crude oil. Salts migrate at electrodes and subsequently removed from the bottom of de-salter.

Quite cost effective and fast process.

Pumping/Transportation of Crude Oil:

Crude oil contains impurities and other waxy materials that make the crude oil in solid or semi solid when such content is high. Typically Indian crude oils contain high wax fraction that leads high pour point of crude i.e. Assam crude oil having wax content 16% with pour point 30 oC. Such crude oils are in solid form in winter season. Solid phase of crude oil causes the major problem in transportation of crude oil. Normally the crude oil exploration site and refineries are located far away from each other. i.e. crude oil from Mehsana to be transported to IOCL Baroda refinery, Bombay high crude oil to Baroda refinery, gulf crude oil to be received at Hazira or Mundra port and then to be transported to Jamnagar or to other parts of India.

Old method of bringing crude oil in liquid form followed by pumping was dilution by water addition up to 20% which results in the emulsion and high pumping cost (20% water has also to be transported). This method obsoletes.

Second method which is widely used in which additives like flowcell, SWAT etc on ppm level are added to convert solid phase into liquid phase by altering the crystal structure of wax present in crude oil. India is pioneer in producing such additives. Additives reduce the pour point as low as 10 to 20 degree C and also reduces viscosity.

The crude oil pipelines are as long as of around 2000 km.

CRUDE OIL REFINING

Crude oil is fractioned in atmospheric distillation unit (ADU) followed by vaccum distillation unit (VDU). The distillation is different than the conventional distillation in-terms of operation and heat supply. No reboiler is used in ADU and VDU to supply heat instead the entire feedstock is heated to a required temperature before it feed into the distillation column. For ADU the crude oil is heated up to 360 oC depending upon quality of crude oil and

processing capacity of distillation unit. Typical throughput capacity varies from 50,000 to 120000 barrels per day of crude oil. For heating such a high flow rate state of the art furnaces are required. The furnaces used for such purpose is known as the Pipe Still Heaters. There are different types of designs available for the same based on shape of the furnace and based on the internal arrangement of tubes & burners.

1) Box/Rectangular2) Cylindrical3) Radiant wall

The modes of heat transfer in pipe still heaters are Radiation and Convection.

For Satisfactory Design typical heat balance is as follows:

Convection H.T.----30-35% Radiant H.T---------45-60% Losses ------------------5% Stack losses------------12%

Recent pipe still Heaters have as high as 70% H.T. by radiation.

(a) Box type

(C) Down Convection type

(e) up-fired (f) Radiant type

Types of Furnaces/Pipe Still Heaters

Factors considered in design of radiant section

Heat Duty:Heating rate is calculated based on projected area or outer surface ares of tube. Typical heat duty requires for ADU varies from 25-50x104 and for VDU 25-30x104 kJ/hr.m2.

Air-fuel ratio:High ratio decreases maximum attainable temperature but increases radiant H.T. by increasing CO2 and H2O partial pressures. The participating radiation plays a major role in radiation heat transfer. The molecules like CO2 and water vapour absorb the heat and then radiate the heat which can be transferred to tubes even not direct visible to the flame of burners. Optimum ratio of Air to fuel is 1.1-1.2.

Tube spacing:The arrangement of tubes inside furnace requires an art. The tubes are to be arranged in such a way that maximum visibility between tubes and flame should be maintained as well as participating radiation should be achieved.

One or two rows of tubes are placed across the walls or at top of the furnace:

For more than two there is a Blanket effect i.e. only 8% H.T. is observed for 3rd row.

Over Burdened Tubes: at common zone of Radiation + Convection or at ducts leading convection zone to radiation zone. Over heating will be observed that reduces the life of tubes as well as promotes cracking of oil. The excessive heating is reported in terms of cross-over temperature.

Combustion volume: As a thumb rule for 11.7x104 kJ/hr of heating rate 1 m3 of furnace

volume is required. The heating space required to heat molecules like water and carbon

dioxide for participating radiation is also considered to arrive at above combustion volume.