INTRODUCTION:
A chimney is a construction designed to aid in the expulsion of hot smoke or flue gas from sources like a fireplace, stove, oven or boiler, into the open air. The chimney is usually positioned vertically to promote an uninterrupted flow of gas through the chimney effect by drawing in air for combustion. The chimney’s height plays a vital role in its capability to discharge the flue gas outside. Furthermore, discharging pollutants at high altitudes can minimize their environmental impact.
Fouling is the accumulation of unwanted substances on solid surfaces which can cause a decrease in their efficiency. It is different from other types of surface growth because it affects a surface that serves a specific and beneficial purpose, and the fouling process obstructs or interrupts its intended function.
Industrial boilers operate at extremely high temperatures and pressures. Some flue gases are produced in the boiler and must be released into the atmosphere through a chimney. During this process, some deposits or fouling can form on the surface of the boiler chimney. Over time, these fouling deposits can accumulate to a substantial level, which shortens the lifespan of the chimney.
Industrial boilers operate at very high temperatures and pressures, producing some flue gases that need to be exhausted into the atmosphere through a chimney. Over time, this process can lead to the build-up of fouling on the chimney surface, which can have a negative impact on the chimney’s lifespan.
Figure 1. Fouling inside boiler chimney
Problem Statement:
The advent of new technologies in the boiler industry has created a demand for more efficient boilers. To ensure that boilers perform optimally, several factors need to be considered. The efficiency of boilers can be impacted by different types of heat loss. The issue faced is that unburned flue gases can accumulate on the inner surface of the chimney, creating a layer of gas known as fouling.
The build-up of fouling on the chimney surface reduces its heat transfer rate, leading to decreased efficiency in the boiler. To solve this problem, measures should be taken to recapture the heat that is lost through the discharge of flue gas from chimneys, while also considering the influence of fouling. The negative impact of fouling can be mitigated by elevating the speed of the flue gases, so measures must be taken to increase the speed of the flue gases.
Literature Review:
Demirbas. A1 This paper discusses the feasible uses of renewable energy sources, particularly biomass, and the obstacles related to its burning process in power boiler systems. The paper also addresses environmental issues related to biomass combustion. The writer presents a thorough evaluation of the present condition of knowledge on the topic and identifies areas for future research. The paper emphasizes the significance of utilizing renewable energy sources, including biomass, to decrease dependence on finite energy sources and minimize the ecological impact of energy generation.
Fargione. J., Hill. J., Tilman. D., Polasky. S., Hawthorne. P2 This paper focuses on the impact of land clearing for the production of biofuels on the carbon cycle. According to the authors, the advantages of utilizing biofuels to mitigate greenhouse gas emissions can be negated by the carbon emissions produced from clearing land and converting natural ecosystems into biofuel crops. The authors provide an estimation of the carbon debt resulting from land clearance for biofuel production, and recommend that this be considered when evaluating the potential benefits of biofuels as a sustainable energy source. The article emphasizes the significance of evaluating the complete life cycle of biofuels, encompassing indirect outcomes like land usage changes, to precisely assess their environmental impact.
Bridgwater A.V.3 The purpose of this article is to give a summary of thermal processing of biomass for the production of renewable fuels and chemicals. The author discusses different thermal processing technologies, such as pyrolysis and gasification, and the article discusses the possibility of utilizing biomass to create biofuels and chemicals, while examining the existing progress and advancements in the field. Additionally, the paper highlights opportunities for future research and development. The author stresses the significance of using biomass as a sustainable source for energy and chemical production to decrease reliance on non-renewable fossil fuels and minimize the environmental impact of energy generation.
Demirbas. M.F., Balat. M., Balat. H4 This paper explores the possible role of biomass in promoting sustainable energy progress. The authors provide a comprehensive review of the current state of knowledge on the utilization of biomass as a source of energy, including the types of biomass, processing technologies, and applications. The authors also discuss the pros and cons of biomass as an infinite energy source, and identify areas for future research and development. The paper highlights the importance of employing biomass as a renewable energy resource, as a way to decrease reliance on limited fossil fuels and alleviate the environmental impact of energy generation, the authors suggest that biomass can have a considerable influence in moving towards a more sustainable energy framework. They contend that biomass possesses the potential to play a crucial role in this transition.
Tchapda. A.H., Pisupati. S.V.5 The purpose of this article is to present an overview of energy production through thermal co-conversion of coal and biomass/waste. The authors discuss different co-conversion technologies, such as co-firing and co-pyrolysis, and the potential for their use in energy production. The authors also review the existing state of investigation and development in the field, and identify areas for future research and development. The authors contend that by co-converting coal and biomass/waste thermally, it is possible to enhance the application of sustainable energy sources, diminish greenhouse gas emissions, and enhance energy efficiency. This paper highlights the importance of considering the use of thermal co-conversion as a means of transitioning to a more sustainable energy system.
Saidur. R., Abdelaziz. E.A., Demirbas. A., Hossain. M.S., Mekhilef. S.6 This article presents an extensive examination of the usage of biomass as a boiler fuel. The authors discuss the various types of biomass, the processing technologies used to convert biomass into fuel, and the potential applications of biomass as a fuel. The authors argue that biomass has the potential to play a crucial role in diminishing reliance on limited fossil fuels, mitigating the effect of energy the environmental consequences of production, and increasing the utilization of renewable energy sources. The paper highlights the importance of considering the use of biomass as a fuel in boilers as a means of transitioning to a more sustainable energy system.
Khan. A.A., de Jong. W., Jansens. P.J., Spliethoff. H.7 This article presents an assessment of the likely issues linked to biomass incineration in fluidized bed boilers. The authors discuss the various forms of biomass, the combustion processes involved, and the potential issues that may arise during combustion. The authors also identify potential remedies for these problems and suggest ways to enhance the effectiveness and eco-friendliness of biomass combustion in fluidized bed boilers. The authors emphasize the importance of considering the potential problems associated with biomass combustion and developing solutions to address them to enhance the usage of sustainable energy resources and mitigate the impact of energy production on the environment. The importance of utilizing biomass combustion in fluidized bed boilers for a more sustainable energy system is emphasized in the paper.
Vassilev. S.V., Baxter. D., Andersen. L.K., Vassileva. C.G., Morgan. T.J.8 This article presents a summary of the composition of biomass, specifically focusing on the organic and inorganic phases. The authors discuss the various categories of biomass, the components which make up the organic and inorganic phases, and the methods used to determine the composition of biomass. The authors also highlight the importance of understanding the composition of biomass in order to optimize its utilization as a fuel and improve its sustainability. The authors of the paper highlight the importance of taking into account the organic and inorganic components of biomass to facilitate the progress of sustainable energy sources and reduce the impact of energy production on the environment.
McKendry. P.9 This article offers an introduction to the subject of biomass and explores its potential as a source of energy. The author discusses the different types of biomass, the methods for producing energy from biomass, and the potential applications of biomass energy. The author emphasizes the significance of biomass as a sustainable source of energy and the necessity for more investigation and progress in this domain. The paper emphasizes the significance of advancing the utilization of biomass as a means of transitioning to a more sustainable energy system and mitigating the consequences of energy production on the environment
MoniKuntal, Bora, S. Nakkeeran10 This paper presents a performance analysis of a coal-fired boiler and focuses on estimating its efficiency. The authors evaluate the boiler's combustion efficiency and determine the heat loss in various components of the boiler. They also provide recommendations for improving the effectiveness of the boiler, such as decreasing excess air, optimizing the fuel-air ratio, and minimizing the stack gas temperature. The paper presents important findings on enhancing the energy efficiency of coal-fired boilers, which can result in considerable financial benefits and decrease the ecological consequences of coal-powered electricity production.
RD Gupta, S Ghai, A Jain11 This research paper discusses strategies for improving the energy efficiency of industrial boilers, using a case study approach. The study highlights the importance of instrument control and monitoring, particularly in identifying energy wastage and implementing corrective measures. The authors also discuss the implementation of technologies that consume less energy, like energy-efficient technologies such as waste heat recovery systems and economizers, and the need for regular maintenance and optimization of boiler operations to ensure maximum efficiency. Overall, the study underscores the importance of adopting a comprehensive approach to energy management in the industrial sector.
Saurabh Awti, Akshay Patil, Vaibhav Narawade, Sujit Agare12 This research paper aims to increase the efficiency of a boiler system by redesigning its chimney to reduce the effects of fouling. The paper discusses the causes and effects of fouling in boilers, as well as the methods used to prevent it. The authors then describe the design and testing of a modified chimney system that reduces the accumulation of unwanted materials in the boiler, thus improving the system efficiency. The outcomes show that the redesign of the chimney system effectively reduces fouling and improves the efficiency of the boiler.
T Lv, Z Guo, Y Gao13 The focus of this research paper is on creating a waste heat recycling system for a power plant boiler, with the objective of enhancing the plant's energy efficiency. The proposed system is designed to recover waste heat from flue gases and utilize it to preheat the air required for combustion. The authors present a thorough overview of the system's specifications, encompassing heat transfer surfaces, heat recovery equipment, and control mechanisms. The paper also presents simulation results showing the potential increase in efficiency and reduction in emissions achievable with the proposed design.
Y Shi, J Wang14 Yuanhao SHI and Jingcheng WANG discusses the problem of accumulation of ash deposits in the boilers of coal-fired power plants, leading to fouling and related issues proposes a method for monitoring and analyzing key variables to improve boiler efficiency. The authors highlight the negative impact of ash fouling on heat transfer, emissions, and maintenance costs, and argue that effective monitoring and analysis of key variables such as coal quality, boiler operation parameters, and sootblower performance can help mitigate the problem. They also provide a case study of a 660 MW supercritical boiler to illustrate the effectiveness of their proposed method.
LE Carrion, RA Dunner, IF Davila15 This research paper discusses the seismic analysis and design of industrial chimneys. The authors provide an overview of the design process for industrial chimneys, including the factors that need to be considered when designing a chimney for seismic loads. The paper also describes various seismic analysis techniques that can be used to ensure the safety and stability of chimneys during earthquakes. The authors conclude that careful design and analysis are necessary to ensure the safety of industrial chimneys, and that seismic considerations should be an integral part of the design process.
A Valero, C Cortes16 The topic of this research paper is the problem of ash fouling in coal-fired utility boilers and proposes on-load cleaning as a potential solution. The paper delves into the monitoring and optimization of this technique for effective implementation. The authors examine various methods of monitoring the level of ash fouling and propose strategies for optimizing on-load cleaning to improve boiler efficiency. The paper provides insights into the impact of ash fouling on boiler performance and outlines methods to mitigate the problem.
RE Barrett, RC Tuckfield, RE Thomas17 The main objective of this research paper is to conduct an extensive survey and analysis of utility data pertaining to slagging and fouling in pulverized coal-fired utility boilers. The authors collected data from multiple sources regarding boiler design and operation, coal properties, and ash characteristics. They analysed the data to identify the factors that contribute to slagging and fouling and to develop strategies for minimizing these problems. The paper includes recommendations for optimizing boiler operation and for selecting coals with low slagging and fouling tendencies.
B Peńa, E Teruel, LI Díez18 The suggestion put forth in this paper is the utilization of soft-computing models to optimize the process of soot-blowing in coal-fired utility boilers. The research delves into various soft-computing techniques, such as artificial neural networks, fuzzy logic, and genetic algorithms, to create predictive models for soot-blowing. The findings of the study indicate that these models can accurately predict the optimal timing and frequency of soot-blowing, resulting in noteworthy enhancements in boiler efficiency and a decrease in emissions. The paper highlights the potential of soft-computing models as an effective tool for the optimization of boiler operation and maintenance.
MM Awad19 This research paper is a review of the fouling phenomenon that affects heat transfer surfaces in various industries. It discusses the causes and mechanisms of fouling, the types of fouling deposits, and their characteristics. The author presents different methods of fouling measurement and analysis, as well as various techniques and strategies for fouling prevention and mitigation. The paper also highlights the importance of fouling control for improving the performance and efficiency of heat exchangers and boilers.
B Kilkovský, V Turek, Z Jegla, P Stehlík20 The focus of this research paper is a comprehensive investigation into fouling occurrences in heat exchangers that deal with contaminated gases. The authors discuss the different types of fouling and their causes, as well as methods for fouling prevention and removal. They also analyse the impact of fouling on heat transfer efficiency and provide recommendations for efficient operation of heat exchangers. The study highlights the importance of fouling management for the optimal performance of heat exchangers in industrial processes.
Fouling:
Fouling is the build-up of substances on solid surfaces that impairs their performance. Typically, this build-up occurs on surfaces that serve a particular and necessary function, making it distinct from other forms of surface growth. The accumulation of fouling obstructs the intended purpose of the surface and interferes with its function.
This article centres around the fouling of industrial heat exchangers as its primary subject matter. However, the principles discussed in the article are relevant to other forms of fouling as well. In the technical realm of cooling technology and its associated fields, macro fouling and micro fouling are distinguished from one another. Among these, micro fouling is generally harder to prevent, and thus considered more important.
Types of Fouling:
1. Macro Fouling:
Macro fouling is induced by sizeable, rough objects derived from either biological or inorganic sources, such as industrial refuse. The cooling water system can be contaminated by various substances that may enter through the cooling water pumps, such as from nearby bodies of water or through open canals, as well as from closed circuits like cooling towers. In some cases, fragments of the cooling tower infrastructure can separate and flow into the cooling water system, resulting in fouling on the surfaces of heat exchangers and a decrease in heat transfer effectiveness. Additionally, macro fouling can cause flow blockages, alter flow patterns within components, or cause fretting damage.
2. Micro Fouling:
Micro fouling refers to the build-up of small or microscopic substances on heat exchanger surfaces, which can impact their performance. Micro fouling can result from the growth of microorganisms such as bacteria, algae, or fungi, or from the accumulation of small particles, like silt or sediment. These substances can form a thin layer on heat exchanger surfaces and reduce their heat transfer efficiency by reducing fluid flow, altering fluid velocity, and increasing fluid turbulence. Micro fouling is often more challenging to prevent than macro fouling because of the small size of the substances involved, but various methods, such as chemical treatments, biocides, or filtration, can be used to address it.
3. Precipitation Fouling:
The process of precipitation fouling involves the accumulation of solid materials such as salts, hydroxides, and oxides that originate from the crystallization of solutions. This typically occurs in water solutions, but can also happen in non-aqueous solutions. The formation of limescale is a common problem in boilers and heat exchangers that use hard water. Precipitation fouling can happen even when there is no heating or vaporization. Calcium sulfate's solubility decreases with pressure reduction, leading to precipitation fouling in oil field reservoirs and wells, which can reduce productivity over time. In reverse osmosis systems, barium sulfate's differential solubility in solutions with varying ionic strength can lead to membrane fouling. Changes in solubility due to factors such as degassing, liquid flashing, alterations in redox potential, or incompatible fluid streams can also cause precipitation fouling.
Why Fouling Occurs:
Material may accumulate on the surface of a heat exchanger as a result of chemical reactions that take place within the fluid stream. A different type of fouling arises from the proliferation of living organisms on surfaces that transfer heat, which is a frequent occurrence when the coolant used is unprocessed water.
The efficiency of a heat exchanger is reduced when deposits, called fouling, accumulate on its surface, impeding heat transfer. Fouling also results in decreased flow cross-section area, which generates a pressure difference across the exchanger and necessitates additional fan power. If fouling persists, it may eventually obstruct the heat exchanger altogether.
Fuel oil that is of inferior quality contains a larger number of alkaline sulphates and vanadium pentoxide, which may result in scaling due to their lower melting points. This type of fouling is more difficult to remove through brushing and sand washing compared to other types of fouling deposits.
The forms of fouling may therefore include,
i. Particulate fouling.
ii. Scaling/precipitation.
iii. Chemical/corrosion fouling.
iv. Solidification.
Boiler Specifications:
Table 1. Specifications of boiler
|
Amount of steam produced by boiler |
15 TPH |
|
Steam operating pressure |
15 bars |
|
Fuel type |
Coal |
|
Rate of combustion |
2023kg/hr |
|
Rate of steam generation |
8954kg/hr |
|
The steam pressure |
14 bars |
|
Temperature of feed water |
90oC |
|
Percentage of CO2 in flue gases |
8% |
|
Percentage of CO in flue gases |
16% |
|
Average temperature of the flue gases |
210oC |
|
Ambient temperature |
27oC |
|
Temperature of boiler surface |
65oC |
|
Wind velocity around the boiler |
4 m/sec |
|
Total surface area of the boiler |
118mm2 |
|
Gross calorific value of the bottom ash |
700K.cal/kg |
|
Gross calorific value of fly ash |
395k.cal/kg |
|
Ratio of bottom ash to fly ash |
90;10 |
|
Ash content in the fuel |
7.80% |
|
Moisture in the fuel |
29% |
|
Carbon Content |
38% |
|
Humidity in the ambient air |
0.018kj/kg of dry air |
Design Calculations:
1) The design of the chimney's outer shell takes into account various stresses such as weight, wind, and lining. The stress due to the chimney's weight is calculated using the formula = fs = 0.0785h N/mm2.
while the stress due to the weight of the lining is calculated using the formula fl=0.002h/t N/mm2. The stress caused by wind is calculated using the formula = fw = (0.004Mwxx)/(πD^2 t) N/mm2.
To ensure stability, the minimum thickness of the shell should be = D/500 which in this case is 1.8 mm.
However, to account for corrosion over the design life of 20 years and the use of coal in the boiler, an additional 4mm thickness is added, making the total minimum thickness of the plate = 10mm.
The effective thickness is then calculated = 6mm by subtracting the additional thickness.
Finally, the maximum compressive force per unit length is represented by fc, while the maximum uplift force per unit length of circumference is represented by ft.
tan(α) = 5000/337.5 = 86.138˚
Now adding the flappers at 3 different angles at 10, 12, 15 degrees
a) at 10 ˚
(β) = 86.138 ˚ - 10 ˚ = 76.138 ˚
tan(β) = h’/337.5
h’ = 1367.70 mm
b) at 12 ˚
(β’) = 86.138 ˚ - 12 ˚ = 74.138 ˚
tan(β) = h’/337.5
h’ = 1187.79 mm
c) at 15 ˚
(β’) = 86.138 ˚ - 15 ˚ = 71.138 ˚
tan(β) = h’/337.5
h’ = 987.89 mm
2) Basic Dimension of the Chimney:
Total height of chimney = 30m
Height of flare = H = 1/3(30) = 10 m
Diameter of the flare =1.6x0.9 = 1.44m.
Computation of wind pressure:
The design wind speed at any height z is given by
Vz=Vb.k1.k2.k3
Where,
Vb = basic wind speed at the site =37m/s for Pune.
k1 = probability factor (risk coefficient) =1.0for general buildings and structures.
k3 = topography factor =1.0 for flat topography
k2 = terrain, height and structure size factor
Vz= 37 x 1 x 1 x k2.
Now design wind pressure,
Pz = 0.6V22
= 0.6 x ( 37 x k2 ) 2 x 10 - 3 kN
= 22.2 k2 KN/m2
For the chimney, taking the shape factor of 0.7,
fz = (Pz x D x Δz) 0.7
3) Calculation of volume flow rate =
Flue gas volume flow rate = n x r2 x V
3.142 × (15.24)2× 10-4×3.7 =6.749 × 10-2 m3/s2
Volume of flow rate of air A = l × w × V
Area of the duct = (20 × 21) × 10-4
4.20 × 10-2 m2
Maximum volume flow rate of air
= Area of duct × velocity at Ѳ = 0o
= 4.2 × 10-2 × 0.95
= 3.99 × 10-2 m3/s
As the air flow rate at fully open duct is still low compared to the flue gas flow rate, it was decided that the subsequent test be carried out at flap angle of 0o in the air duct.
4) Transient Test:
Important parameters include,
Dwell time Ѳd
Normalized time Ѳ*
Time to reach steady state Ѳ
Dwell time is the time air is in contact with the heat transfer surface from entry to exit of exchanger core. It is given by: Ѳd = L/V where L= length of heat exchanger from inlet to outlet to exit.
M
V= ---------------------------------
QTcBxnumber of passages
ρ = air density
Ac = minimum free flow area in the exchanger
The normalized time is the ratio of time the air
temperature takes to reach a constant value to the dwell time i.e. 
= Ѳ
CAD Model:
CATIA V5 software was utilized to create the CAD model. The V section measures 5000 mm in height, has the Outer diameter as 900 mm, and the Base diameter as 1575 mm.
Figure 2: CAD model of chimney segment
The figures below display the flappers that were designed with angles of 10, 12, and 15 degrees.
Figure 3: Flapper at 10o
Figure 4: Flapper at 12o
Figure 5: Flapper at 15o
The figure below illustrates the assembly of the chimney segment and flapper at 10o.
Figure 6: Assembly of chimney segment with flapper at 10o
CFD Analysis:
Here we get to see the velocity of flue gases. The velocity is very low without the Flappers; hence the flue gases leave the chimney at low velocity. Due to that fouling occurs in the inside of the Chimney and its efficiency decreases.
Figure 7: Without Flappers
With Flapper of 10°:
Figure 8: With Flapper of 10°
After installing the Flapper of 10° we saw that the change in velocity inside the chimney is maximum. If we decrease the angle less than 10-degree, back pressure will develop in the Chimney. The Velocity of flue gases increases as seen in CFD Analysis. As a result, the chimney is exposed to the hot flue gases for a shorter duration, which reduces the occurrence of fouling. So, we selected the 10-degree angle and found out the changes in efficiency.
Changes in the flow according to flapper angle are below which are:
1. With Flapper of 12°
2. With Flapper of 12°
With Flapper of 12°:
Figure 9: With Flapper of 12
With Flapper of 15°:
Figure 10: With Flapper of 15°
CFD Pressure Analysis:
Figure 11. CFD Pressure Analysis
Here we can see that there is slightly Decrease in pressure as soon as the flue gases leaves through the Flapper installed. The relationship between velocity and pressure in the chimney is such that if the velocity increases, the pressure will decrease due to their inverse proportionality. We can confirm it by the Green Color code shown in the Diagram.
CFD Velocity Analysis:
Figure 12: CFD Velocity Analysis
Here we can see that there is slightly Increase in Velocity as soon as the flue gases leaves through the Flapper installed. If the velocity increases, the pressure inside the chimney will decrease due to the inverse relationship between velocity and pressure. We can confirm it by the Green Color code shown in the Diagram. The rate of fouling is decreased as an outcome of the hot flue gases spending less time in contact with the chimney due to an increase in velocity.
Result without Flapper
Table No. 02
|
Steam Generation Rate |
8950 Kg/hr |
|
Steam Pressure |
14 Bar |
|
Feed Water Temperature |
90° C |
|
Of Co2 In Flue Gases |
8 % |
|
Of Co In Flue Gases |
1.6 % |
|
Average Flue Gas Temperature |
115° C |
|
Ambient Temperature |
27° C |
|
Humidity In Ambient Air |
0.018 KJ/Kg of Dry Air |
|
Surface Temperature of Boiler |
65° C |
|
Wind Velocity Around Boiler |
4 m/sec |
|
Total Surface Area of Boiler |
118 mm2 |
|
Fuel Analysis In % |
|
|
Ash Content in Boiler |
7.80 % |
|
Carbon Content |
38.0 % |
|
Nitrogan Content |
1.90 % |
|
Oxygen Content |
5.0 % |
|
Cv Of Coal |
3450 to 3580 kCal/kg |
|
Flue Gas Temperature |
315° C |
|
Thermal Efficiency |
92.95 % |
|
Ash Fusion Temperature |
1100 ° C |
|
Fuel Consumption |
2014 kg/hr |
|
Steam Temperature |
320° C |
|
Boiler Efficiency |
46.2 % |
Result With Flapper:
Table No. 03
|
Steam Generation Rate |
9030 Kg/hr |
|
Steam Pressure |
13 Bar |
|
Feed Water Temperature |
90° C |
|
Of CO2 In Flue Gases |
8 % |
|
Of Co In Flue Gases |
1.6 % |
|
Average Flue Gas Temperature |
130° C |
|
Ambient Temperature |
27° C |
|
Surface Temperature Of Boiler |
65° C |
|
Wind Velocity Around Boiler |
4 m/sec |
|
Total Surface Area Of Boiler |
118 mm2 |
|
Fuel Analysis in % |
|
|
Ash Content in Fuel |
7.80 % |
|
Carbon Content |
38 % |
|
Nitrogan Content |
1.90 % |
|
Oxygen Content |
5.0 % |
|
Cv Of Coal |
3450 to 3580 kCal/kg |
|
Flue Gas Temperature |
215° C |
|
Thermal Efficiency |
92.95 % |
|
Ash Fusion Temperature |
1100 ° C |
|
Fuel Consumption |
2014 kg/hr |
|
Steam Temperature |
320° C |
|
Boiler Efficiency |
49.7 % |
Steam generation without flapper = 8950 kg/hr
Fuel consumption = 2014 kg/hr
Steam generation with flapper = 9030 kg/hr
Fuel Consumption = 2014 kg/hr
Percentage increase in the Boiler Efficiency: -
(Output / Input) *100 = (80/2014) *100= 0.0397*100 = 3.94%
CONCLUSION:
By placing flappers at various angles in the fifth section of the chimney (10, 12, and 15 degrees), the issue of fouling was the focus of the research. The aim was to find a solution to this problem and conducting a Computational Fluid Dynamics (CFD) analysis on the outcomes. The results illustrated that the installation of flappers enhanced the velocity of flue gases, leading to a reduction in fouling, which in turn improved the efficiency of the chimney and extended its lifespan. The findings of this research provide a promising solution to fouling in chimneys and may have practical implications for the design and maintenance of industrial chimneys. It is recommended that further research be conducted to explore the long-term effects of flapper installation on chimney performance. To develop and evaluate the model of the systems, conditions of forced convection were utilized.
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Received on 31.03.2023 Accepted on 10.05.2023 © EnggResearch.net All Right Reserved Int. J. Tech. 2023; 13(1):22-34. DOI: 10.52711/2231-3915.2023.00003 |
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