The document discusses the chemistry of fuels. It defines fuels as substances that undergo combustion, producing heat. Fuels can be classified by origin as primary/natural (coal, wood) or secondary/artificial (petrol, diesel). They can also be classified by physical state as solid, liquid or gaseous. The document outlines various fuel properties that are tested like calorific value, ignition temperature and viscosity. It also discusses fuel combustion and calculations to determine the air required for complete combustion of a fuel. Methods for analyzing the chemical composition of fuels are provided.
Primary fuels – Fuels which occur naturally such as coal, crude petroleum and natural gas. Coal and crude petroleum, formed from organic matter many millions of years ago, are referred to as fossil fuels.
Secondary fuels – Fuels which are derived from naturally occurring ones by a treatment process such as coke, gasoline, coal gas etc.
The substitution of fuels known as fossil or traditional, derived from petroleum represents one of the great challenges facing humanity currently. One of the alternatives is to replace the diesel oil using the production of biodiesel. This is a renewable fuel derived from vegetable oils (edible or inedible, new or used) and animal fats that have properties similar to oil.
In petroleum refining, the Crude Distillation Unit (CDU) (often referred to as the Atmospheric Distillation Unit) is usually the first processing equipment through which crude oil is fed. Once in the CDU, crude oil is distilled into various products, like naphtha, kerosene, and diesel, that then serve as feedstocks for all other processing units at the refinery.
In this project we basically studied scope of this project, its feasibility and market assessment, raw material availability, different routes to produce Syngas and their comparison, process selection and its complete description, its P&ID, and environmental consideration.
Hydrogen Production through Steam Reforming process.pptxFAHADMUMTAZ10
The Presentation is about the production of steam reforming process, its purity. Meanwhile, I have also discussed the other processes. I have also discussed the future trends of hydrogen in Germany and its bright future!
Primary fuels – Fuels which occur naturally such as coal, crude petroleum and natural gas. Coal and crude petroleum, formed from organic matter many millions of years ago, are referred to as fossil fuels.
Secondary fuels – Fuels which are derived from naturally occurring ones by a treatment process such as coke, gasoline, coal gas etc.
The substitution of fuels known as fossil or traditional, derived from petroleum represents one of the great challenges facing humanity currently. One of the alternatives is to replace the diesel oil using the production of biodiesel. This is a renewable fuel derived from vegetable oils (edible or inedible, new or used) and animal fats that have properties similar to oil.
In petroleum refining, the Crude Distillation Unit (CDU) (often referred to as the Atmospheric Distillation Unit) is usually the first processing equipment through which crude oil is fed. Once in the CDU, crude oil is distilled into various products, like naphtha, kerosene, and diesel, that then serve as feedstocks for all other processing units at the refinery.
In this project we basically studied scope of this project, its feasibility and market assessment, raw material availability, different routes to produce Syngas and their comparison, process selection and its complete description, its P&ID, and environmental consideration.
Hydrogen Production through Steam Reforming process.pptxFAHADMUMTAZ10
The Presentation is about the production of steam reforming process, its purity. Meanwhile, I have also discussed the other processes. I have also discussed the future trends of hydrogen in Germany and its bright future!
Coal is composed primarily of carbon along with variable quantities of other elements, chiefly hydrogen, sulphur, oxygen, nitrogen. Ultimate analysis is also known as elemental analysis, it is the method to determine the Carbon,Hydrogen,Nitrogen,Sulphur and Oxygen content present in solid fuel.
This is a lecture is a series on combustion chemical kinetics for engineers. The course topics are selections from thermodynamics and kinetics especially geared to the interests of engineers involved in combusition
In coal fired power plants coal is a main fuel for combustion purpose. Before use of coal different tests are to be carried out to analysis the constituent elements and some undesirable contamination in the coal. Discuss the analysis procedures of the coal.
The analysis of coal is as follows C=82%, H=6%,O2=4% and remaining is ash. Determine the amount of theoretical air required for complete combustion. If the actual air supplied is 40% in excess and 80% of given carbon is burnt to CO2 and remaining is CO. Conduct the volumetric analysis of dry products of combustion.
Fuel is a combustible substance, containing carbon as main constituent, which...drmanojkarar
Energy resources: While selecting an ideal fuel for domestic or industrial purpose we should keep in mind that the fuel selected must possess the following characteristic properties.
1) It should possess high calorific value.
2) It should have proper ignition temperature. The ignition temperature of the fuel should neither be too low nor too high.
3) It should not produce poisonous products during combustion. In other words, it should not cause pollution o combustion.
4) It should have moderate rate of combustion.
5) Combustion should be easily controllable i.e., combustion of fuel should be easy to start or stop as and when required.
6) It should not leave behind much ash on combustion.
7) It should be easily available in plenty.
8) It should have low moisture content.
9) It should be cheap.
10) It should be easy to handle and transport.
Calorific value: It is defined as the total amount of heat liberated, when unit mass or unit volume of the fuel is completely burnt in air or oxygen.
Units of heat:
a) Calorie: The amount of heat required to increase the temperature of 1 gm of water through one degree centigrade.
b) Kilocalorie: It is equal to 1000 calories. The quantity of heat required to rise the temperature of 1 Kg of water through one degree centigrade.
1 K.cal = 1000 cals
c) British thermal unit (B.Th.U.): The quantity of heat required to rise the temperature of 1 pound of water through one degree Farenheit.
1 B.Th.U = 252 cals = 0.252 K.cal
d) Centigrade heat unit (C.H.U): The quantity of heat required to rise the temperature of one pound of water through one degree centigrade.
1 K. cal = 3.968 B.Th.U = 2.2 C.H.U
For solids or liquid fuel: Calorie/gm (cal/gm) (or) Kilocalorie/Kg (K.cal/Kg) (or) B.Th.U/lb
For gaseous fuels: Kilocalorie/cubic meter (K.cal/m3) (or) B.Th.U/ft3
Classification of Fuel, Characteristics of good fuel, Calorific value and types of calorific value, bomb calorimeter, Boys calorimeter ,numerical s on bomb calorimeter, Boys calorimeter
Calorimeter to measure the calorific value of fuelsatechnicalboard
Calorimetry is the field of science that deals with the measurement of the state of a body with respect to the thermal aspects in order to examine its physical and chemical changes. The changes could be physical such as melting, evaporation or could also be chemical such as burning, acid-base neutralisation etc.
A calorimeter is what is used to measure the thermal changes of a body.
Calorimetry is applied extensively in the fields of thermochemistry in calculating the enthalpy, stability, heat capacity etc.
What Is a Calorimeter?
A calorimeter is a device used for heat measurements necessary for calorimetry. It mainly consists of a metallic vessel made of materials which are good conductors of electricity such as copper and aluminium etc. There is also a facility for stirring the contents of the vessel. This metallic vessel with a stirrer is kept in an insulating jacket to prevent heat loss to the environment. There is just one opening through which a thermometer can be inserted to measure the change in thermal properties inside. Let us discuss how exactly heat measurements are made. In the previous article, we discussed the specific heat capacity of substances.
Such measurements can be made easily with this. Say in a calorimeter a fixed amount of fuel is burned. The vessel is filled with water, and the fuel is burned, leading to the heating of the water. Heat loss by the fuel is equal to the heat gained by the water. This is why it is important to insulate the calorimeter from the environment; to improve the accuracy of the experiment. This change in heat can be measured through the thermometer. Through such a measurement, we can find out both the heat capacity of water and also the energy stored inside a fuel.
Uses of Calorimetry
It is well known now that matter always obeys the principle of lowest energy i.e. given the option, the matter will exist in the lowest energy state possible. Despite this, matter can have a variety of energetic states. Uranium atoms, for example, are a powerhouse.
The energy of matter has a profound effect on its natural occurrence and its reactivity etc. If we can unravel the relationship between them, then we can predict the natural occurrence, reactivity and physical properties based on the energy measurements we make through calorimetry. Understanding the thermodynamic properties of a substance will inevitably yield answers to structure and other properties.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
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Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
1. *
CHEMISTRY OF FUELS
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2. *
• Fuels: substances which undergo combustion in
the presence of air to produce a large amount of
heat that can be used economically for domestic
and industrial purpose.
• This definition does not include nuclear fuel because
it cannot be used easily by a common man.
• The various fuels used economically are wood, coal,
kerosene, petrol, diesel gasoline, coal gas, producer
gas, water gas, natural gas (LPG) etc.
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3. *
Classifications
Fuels can be broadly classified by origin as,
(i)Primary or natural fuels: coal, wood etc
(ii)Secondary or artificial or derived fuels: petrol, diesel
On the basis of physical state, as :
(i) Solid fuels
(ii) Liquid fuels
(iii) Gaseous fuelsV
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4. *
Basis Origin Physical
State
Source Natural or
primary
Artificial or
Secondary or
Derived
Wood, peat, lignite,
coal
Semi coke, charcoal Solid fuels
Crude oil,
Vegetable oils
Petrol, kerosene,
gas oil, coal tar,
alcohol
Liquid
fuels
Natural gas Producer gas, coke-oven
gas, water
gas, blast furnace
gas, compressed
butane gas, LPG
Gaseous
fuels
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5. *
Characteristics of Fuels
The physical properties for which fuels are tested
and their ideal requirements are listed below :
(i)Calorific value or specific heat of combustion.
- efficiency of fuel: how much heat it produces
(ii) Ignition temperature
(iii) Flame temperature
(iv) Flash and Fire point.
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6. *
(v) Aniline point
(vi) Knocking.
(vii) Specific gravity
(viii) Cloud and Pour point
(ix) Viscosity
(x) Coke number.
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7. *
The chemical properties include the compositional
analysis of fuel.
For solid and liquids fuels :
(i) Percentage of various elements such as C, H, O,
N, S, etc.
(ii) Percentage of moisture
(iii) Percentage of volatile matter
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8. *
For gaseous fuels :
(i) Percentage of combustible gases e.g. – CO, H2,
CH4, C2H4, C2H6, C4H10, H2S etc.
(ii) Percentage of non-combustible gases e.g. N2,
CO2 etc.
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9. *
Calorific Value
• number of units of heat evolved during complete
combustion of unit weight of the fuel.
• A British Thermal Unit: the heat required to raise
the temperature of one pound of water from 60° F to
61° F.
• The Calorie: the heat required to raise the temperature
of one kg of water from 15°C to 16°C.
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10. *
High and Low Calorific Values
Calorific values are of two types as,
(i)High or Gross Calorific Value (H.C.V. or G.C.V.)
(ii)Low or Net Calorific Value (L.C.V. or N.C.V.)
High calorific value may be defined as, the total
amount of heat produced when one unit of the fuel
has been burnt completely and the combustion
products have been cooled to 16°C or 60°F.
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11. *
• LCV: is the net heat produced when unit mass or
volume of fuel is completely burnt and products are
allowed to escape.
• Net or Low C.V.= Gross C.V. – loss due to water
formed
• Or Gross C.V – Mass of hydrogen ´ 9 ´ Latent heat
of steam (587 cal/g)
• (Because 1 part by weight of hydrogen produces 9
parts (1 + 8) by mass of water)
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12. *
• The calorific value of fuels (e.g. Coal) is determined
theoretically by Dulong formula, or I.A. Davies
formula.
• Dulong formula can be expressed as,
HCV = 1/100 [8,080 C+ 34,500(H- O/8)+ 2240 S]
Where C = % Carbon, H = % Hydrogen, O = %
Oxygen, S = % Sulphur
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13. *
• Oxygen in fuel (coal) is in combined state as
water and hence it does not contribute to
heating value of fuel.
• LCV = [HCV – 0.09 H(%) × 587] cal/g
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14. *
Bomb Calorimeter
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15. *
• Let x = mass in g of fuel taken in crucible
• W = mass of water in calorimeter
• w = water equivalent in g of calorimeter, stirrer, thermometer,
bomb etc.
• t1 & t2 are initial & final temperatures of water in calorimeter
• L = higher calorific value of fuel in cal/g
• Then heat liberated by buring of fuel = xL
• Heat absorbed by water & apparatus = (W+w)(t2-t1)
• But heat liberated by fuel = heat absorbed by water, apparatus
• so, xL = (W+w)(t2-t1)
• L = (W+w)(t2-t1)/x cal/g or kcal/kg
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16. • If H = % of hydrogen in fuel
• 9H/100 g = mass of water from 1 g of fuel= 0.09H g
• So heat taken by water in forming steam = 0.09 H ×
587 cal
• LCV = HCV - 0.09 H × 587 cal/g
• By considering fuse wire correction, acid correction
& cooling corection
• L = [{(W+w)(t2-t1+ cooling correction)}- {acid +fuse
correction}]/x cal/g or kcal/kg
*
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17. *
Sr.
No.
Property Solid Fuels Liquid Fuels Gaseous Fuels
1. Calorific value Low Higher Highest
2. Specific gravity Highest Medium Lowest
3. Ignition point High Low Lowest
4. Efficiency Poor Good Best
5. Air required for
combustion
Large and excess
of air
Less excess of air Slight excess of air
6. Use in I.C. engine Cannot be used Already in use Can be used
7. Mode of supply Cannot be piped Can be piped Can be piped
8. Space for storage Large 50% less than solid
fuel
Very high space
9. Relative cost Cheaper Costly More costly than
other two
10. Care in storage and
transport
Less care required Care is necessary Great care required
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18. *
Combustion
• Combustion is a process in which oxygen from the
air reacts with the elements or compounds to give
heat.
• As the elements or compounds combine in indefinite
proportions with oxygen, we need to calculate what is
minimum oxygen or air required for the complete
combustion of compounds. The commonly involved
combustion reactions are :
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19. i) C + O2 ® CO2
ii) 2H2 + O2 ® 2H2O OR H2 + (O) ® H2O
iii) S + O2 ® SO2
iv) 2CO + O2 ® 2CO2 OR CO + (O) ®
*
CO2
v) CH4 + 2O2 ® CO2 + 2H2O
vi) 2C2H6 + 7O2 ® 4CO2 + 6H2O
vii) C2H4 +3O2®
2CO2 + 2H2O
viii) 2C2H2 + 5O2 ® 4CO2 + 2H2O
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20. *
Hint to Solve Problems on Calculation of Quantity of Air
Required for Combustion of Fuel :
• 1. First write the appropriate chemical reaction with oxygen and find their
relation between the element or compound on weight or volume basis.
e.g C + O2 ® CO2
by weight (12 gm) + (32 gm) (44gm)
by volume 1 1 1
2H2 + O2 ® 2H2O
by weight (4 gm) + (32 gm) (36gm)
by volume 2 1 2
S + O2 ® SO2
by weight (32 gm) + (32 gm) (64gm)
by volume 1 1 1
21. *
2) Calculate the oxygen required on the basis of unit quantity of
fuel.
3) Calculate the total oxygen required for the combustion and
subtract the oxygen which is present in the fuel.
4) The oxygen calculated should be converted into air by
knowing that air contains 23 parts by weight of oxygen OR 21
parts by volume of oxygen.
5) The average molecular weight of air is 28.94 gm.
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22. *
Calculate the weight and volume of air required
for complete combustion of 5 kg. coal with
following compositions, C = 85%; H = 10%;
O = 5%
Soln. :
Combustion reactions :
C + O2 ® CO2
12 + 32 ® 44
H2 + O2 ® H2O
2 + 16 ® 18
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23. *
Weight of
elements per kg.
of coal
Weight of O2 required
for complete combustion
in kg.
C = 0.85 0.85 ´32/12 = 2.26 kg.
H = 0.1 0.1 ´ 8 = 0.8 kg.
O = 0.05 –
Total oxygen = 3.06 kg.
Weight of oxygen required
= Weight of oxygen needed – weight of oxygen present
= 3.06 – 0.05 = 3.01
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24. *
Air required for complete combustion
= 3.01 ´ 100/23
= 13.08 kg. per 1 kg. coal.
Air required for 5 kg. of coal
= 13.08 ´ 5 = 65.40 kg.
Volume of Air
28.94 kg. of air = 22,400 ml volume at NTP
65.4 kg. of air =22400× 65.4/ 28.94
=50815.8 ml. Air
=50.8158 litres of air
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25. *
Sr
No
Types
of Coal
Classification of Coal
Moisture
of Air
Dried At
40°C
C%
H%
O%
Ash
%
Calorific
Value
(kcal/kg)
Uses
1. Peat 25 57 6 35 2 5400 Power generation and
domestic purpose.
2. Lignite 20 67 5 20 8 6500 Manufacture of
producer gas, thermal
power plants.
3. Bitumi
nous
4 83 5 15 7 8000 For metallurgical
coke, coal gas, boiler,
domestic purpose
4. Anthra
cite
2 92 3 2 3 8600 Boilers, metallurgical
fuel, domestic
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26. *
Analysis of Coal
The proximate analysis is easy and quicker and it gives a fair
idea of the quality of coal.
The ultimate analysis is essential for calculating heat
balances in any process for which coal is employed as a fuel.
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27. *
Moisture
• It is determined by heating about one gm. of finely
powdered coal at 105°C to 110°C for an hour in
electric oven. The loss in weight is reported as due to
moisture.
• % Moisture = [loss in wt of sample × 100]/wt of coal
taken
• Decreases calorific value of coal
• Takes away heat in the form of latent heat
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28. *
Volatile matter
• For determining volatile matter content, a known
weight of dried sample is taken in a crucible with
properly fitting lid. It is then heated at 950°C ± 20°C
for exactly seven minutes in previously heated muffle
furnace. The loss in weight is due to volatile matter
which is calculated as
• Volatile matter = [loss in wt at 9500C × 100]/wt of
coal sample
• Decreases calorific value
• Forms smoke and pollutes air
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29. *
Ash (non combustible matter)
• A known weight of sample is taken in a crucible and
the coal is burnt completely at 700°C – 750°C in
muffle furnace until a constant weight is obtained.
The residue left in the crucible is ash content in coal
which is calculated as
• % of Ash = [wt of residue left in crucible´ 100]/ wt
of coal taken
• Reduces calorific value as it is non burning part
• Ash disposal is a problem
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30. *
Fixed carbon
% of Fixed carbon = 100 – (% of moisture + % of ash +
% of volatile matter)
• In any good sample of coal, the percentages of
moisture, ash, volatile matter should be as low as
possible and thus the percentage of fixed carbon
should be as high as possible.
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31. *
Determination of C & H
• Accurately weighed coal sample is burnt in a current
of oxygen in a combustion apparatus, which is heated
to about 350°C.
• Carbon and hydrogen of coal are converted into water
vapour and carbon-dioxide. The products of
combustion are absorbed in anhydrous CaCl2 and
KOH tubes respectively of known weights.
• After complete absorption of H2O and CO2, the tubes
are again weighted.
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32. *
C + O2 ® CO2
12 parts ® 44 parts
2H2 + O2 ® 2H2O
4 parts ® 36 parts
• % of Carbon = [increase in wt of KOH tube × 12 ×
100]/wt of coal taken × 44
• % of Hydrogen =[increase in wt of CaCl2 tube × 4
´100]/wt of coal taken × 36
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33. *
Determination of Nitrogen
Nitrogen is calculated by Kjehldals Method.
The nitrogen is converted to NH3 and passed through a known volume
of standard acid. On neutralization, the excess acid is back titrated
with a base.
1000 ml of x N acid 14 gm of Nitrogen
% N = [volume of acid consumed in neutralizing NH3 × N x 14 x 100
wt of coal taken x 1000
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34. Determination of Sulphur
% Sulphur: [wt of BaSO4 obtained × 32×
100]/wt of coal taken × 233
Determination of Oxygen:
The oxygen is determined indirectly by
calculation as
% of Oxygen = 100 – (% of C + % of H + % of
N + % of S + % of Ash)
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*
35. Importance of Ultimate analysis:
• Carbon: Greater the % carbon, better is the quality and
calorific value of coal
• Hydrogen: most of hydrogen is in form of moisture and
volatile matter. Only a small % is combustible, hence it
decreases C.V. Smaller the H% better is quality of coal
• Nitrogen: does not burn, hence it has no C.V. Negligible
N% is good coal
• Sulphur: it increases C.V, but causes Sox pollution.
Hence lower S% is better
• Oxygen: most of oxygen is in form of moisture, hence it
decreases C.V. Smaller the H% better is quality of coal *