A Method for Combustion Calculation Based on Proximate Analysis and Net Calorific Value of Coal

For the combustion calculation of coal fired boiler, a new concept of oxygen consumption for combustible material was proposed which was different from the traditional oxygen consumption for elements. A mathematical model was developed for the combustion calculation. The calculation formulas of theoretical air and flue gas volume were established through reasonable hypothesis and simplification, which were based on proximate analysis and net calorific value of coal. In contrast to the results of the elemental analysis for the 15 different kinds of coals which are typical in China, the average relative error of formulas is lower than 2%, the biggest relative error is 7.11%, which can be used for the control over boiler operation, testing and debugging, and calculation of heat transfer.

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Waste to Energy: An Assessment of Application of the Selective Fuel for Applications in Industries using a Mixture of "A" Grade Coal and Municipal Solid Waste

Journal of the Institute of Engineering ◽

10.3126/jie.v12i1.16887 ◽

2017 ◽

Vol 12 (1) ◽

pp. 129-142 ◽

Cited By ~ 1

Author(s):

Nripendra Bajracharya ◽

Bhakta Bahadur Ale ◽

Ramesh Man Singh ◽

Tri Ratna Bajracharya

Keyword(s):

Flue Gas ◽

Calorific Value ◽

Industrial Sector ◽

Proximate Analysis ◽

Waste To Energy ◽

Small Scale ◽

Index Test ◽

Gas Emission ◽

So2 Emission ◽

Refuse Derived Fuel

This paper is about how the garbage that is considered as nuisance can actually be a source of energy that is vital for us. The fuel prepared by blending combustible fraction of waste is called refuse derived fuel (RDF). When the waste is mixed with coal known as selective fuel, they can be the replacement for coal in industries. The vertical shaft brick kiln (VSBK) has been taken as a representative of industrial sector. This is the theme of this research. The coal sample used is from Assam, India which is the A grade coal normally used in VSBKs of Nepal. The selective fuel was undergone proximate analysis, smoke index test, flue gas emission test and was also tested for its calorific value. The moisture content and ash content is found to be 8.69% and 11.21% respectively which is the acceptable range for VSBK. The fixed carbon content of the fuel is 28.03%. The sulphur content of the coal is 6.4% which can be captured using Ca(OH2. Addition of lime and presence of excess air help to control smoke during combustion. Flue gas emission test shows CO emission of 56.66 ppm, CO2 emission of 2% and no SO2 emission. The economic analysis shows that installation of small scale briquetting plant is feasible. Besides this, mathematical calculation has also been done to deduce some results.Journal of the Institute of Engineering, 2016, 12(1): 129-142

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Thermal load non-uniformity estimation for superheater tube bundle damage evaluation

MATEC Web of Conferences ◽

10.1051/matecconf/201815702033 ◽

2018 ◽

Vol 157 ◽

pp. 02033 ◽

Cited By ~ 1

Author(s):

Martin Naď ◽

Zdeněk Jegla ◽

Tomáš Létal ◽

Pavel Lošák ◽

Jiří Buzík

Keyword(s):

Heat Transfer ◽

Flue Gas ◽

Thermal Load ◽

Gas Flow ◽

Cfd Simulation ◽

Tube Bundle ◽

Temperature History ◽

Damage Evaluation ◽

Complex Flow ◽

Boiler Operation

Industrial boiler damage is a common phenomenon encountered in boiler operation which usually lasts several decades. Since boiler shutdown may be required because of localized failures, it is crucial to predict the most vulnerable parts. If damage occurs, it is necessary to perform root cause analysis and devise corrective measures (repairs, design modifications, etc.). Boiler tube bundles, such as those in superheaters, preheaters and reheaters, are the most exposed and often the most damaged boiler parts. Both short-term and long-term overheating are common causes of tube failures. In these cases, the design temperatures are exceeded, which often results in decrease of remaining creep life. Advanced models for damage evaluation require temperature history, which is available only in rare cases when it has been measured and recorded for the whole service life. However, in most cases it is necessary to estimate the temperature history from available operation history data (inlet and outlet pressures and temperatures etc.). The task may be very challenging because of the combination of complex flow behaviour in the flue gas domain and heat transfer phenomena. This paper focuses on estimating thermal load non-uniformity on superheater tubes via Computational Fluid Dynamics (CFD) simulation of flue gas flow including heat transfer within the domain consisting of a furnace and a part of the first stage of the boiler.

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Evaluasi Prediksi Higher Heating Value (HHV) Biomassa Berdasarkan Analisis Proksimat

Risalah Fisika ◽

10.35895/rf.v4i1.166 ◽

2020 ◽

Vol 4 (1) ◽

pp. 1-7

Author(s):

Made Dirgantara ◽

Karelius Karelius ◽

Marselin Devi Ariyanti, Sry Ayu K. Tamba

Keyword(s):

Renewable Energy ◽

Natural Gas ◽

Key Words ◽

Critical Analysis ◽

Fossil Fuels ◽

Calorific Value ◽

Proximate Analysis ◽

Heating Value ◽

Bomb Calorimeter ◽

Hhv Prediction

Abstrak – Biomassa merupakan salah satu energi terbarukan yang sangat mudah ditemui, ramah lingkungan dan cukup ekonomis. Keberadaan biomassa dapat dimaanfaatkan sebagai pengganti bahan bakar fosil, baik itu minyak bumi, gas alam maupun batu bara. Analisi diperlukan sebagai dasar biomassa sebagai energi seperti proksimat dan kalor. Analisis terpenting untuk menilai biomassa sebagai bahan bakar adalah nilai kalori atau higher heating value (HHV). HHV secara eksperimen diukur menggunakan bomb calorimeter, namun pengukuran ini kurang efektif, karena memerlukan waktu serta biaya yang tinggi. Penelitian mengenai prediksi HHV berdasarkan analisis proksimat telah dilakukan sehingga dapat mempermudah dan menghemat biaya yang diperlukan peneliti. Dalam makalah ini dibahas evaluasi persamaan untuk memprediksi HHV berdasarkan analisis proksimat pada biomassa berdasarkan data dari penelitian sebelumnya. Prediksi nilai HHV menggunakan lima persamaan yang dievaluasi dengan 25 data proksimat biomassa dari penelitian sebelumnya, kemudian dibandingkan berdasarkan nilai error untuk mendapatkan prediksi terbaik. Hasil analisis menunjukan, persamaan A terbaik di 7 biomassa, B di 6 biomassa, C di 6 biomassa, D di 5 biomassa dan E di 1 biomassa.Kata kunci: bahan bakar, biomassa, higher heating value, nilai error, proksimat Abstract – Biomass is a renewable energy that is very easy to find, environmentally friendly, and quite economical. The existence of biomass can be used as a substitute for fossil fuels, both oil, natural gas, and coal. Analyzes are needed as a basis for biomass as energy such as proximate and heat. The most critical analysis to assess biomass as fuel is the calorific value or higher heating value (HHV). HHV is experimentally measured using a bomb calorimeter, but this measurement is less effective because it requires time and high costs. Research on the prediction of HHV based on proximate analysis has been carried out so that it can simplify and save costs needed by researchers. In this paper, the evaluation of equations is discussed to predict HHV based on proximate analysis on biomass-based on data from previous studies. HHV prediction values using five equations were evaluated with 25 proximate biomass data from previous studies, then compared based on error value to get the best predictions. The analysis shows that Equation A predicts best in 7 biomass, B in 6 biomass, C in 6 biomass, D in 5 biomass, and E in 1 biomass. Key words: fuel, biomass, higher heating value, error value, proximate

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An Experimental Investigation of Water Vapor Condensation from Biofuel Flue Gas in a Model of Condenser, (1) Base Case: Local Heat Transfer without Water Injection

Processes ◽

10.3390/pr9050844 ◽

2021 ◽

Vol 9 (5) ◽

pp. 844

Author(s):

Robertas Poškas ◽

Arūnas Sirvydas ◽

Vladislavas Kulkovas ◽

Povilas Poškas

Keyword(s):

Heat Transfer ◽

Water Vapor ◽

Flue Gas ◽

Waste Heat Recovery ◽

Waste Heat ◽

Water Injection ◽

Vapor Condensation ◽

Base Case ◽

Water Vapor Condensation ◽

Condensing Heat Exchanger

Waste heat recovery from flue gas based on water vapor condensation is an important issue as the waste heat recovery significantly increases the efficiency of the thermal power units. General principles for designing of this type of heat exchangers are known rather well; however, investigations of the local characteristics necessary for the optimization of those heat exchangers are very limited. Investigations of water vapor condensation from biofuel flue gas in the model of a vertical condensing heat exchanger were performed without and with water injection into a calorimetric tube. During the base-case investigations, no water was injected into the calorimetric tube. The results showed that the humidity and the temperature of inlet flue gas have a significant effect on the local and average heat transfer. For some regimes, the initial part of the condensing heat exchanger was not effective in terms of heat transfer because there the flue gas was cooled by convection until its temperature reached the dew point temperature. The results also showed that, at higher Reynolds numbers, there was an increase in the length of the convection prevailing region. After that region, a sudden increase was observed in heat transfer due to water vapor condensation.

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Improving heat transfer and water recovery performance in high‐moisture flue gas condensation using silicon carbide membranes

International Journal of Energy Research ◽

10.1002/er.6581 ◽

2021 ◽

Author(s):

Chao Ji ◽

Li Li ◽

Hong Qi

Keyword(s):

Heat Transfer ◽

Silicon Carbide ◽

Flue Gas ◽

Water Recovery ◽

High Moisture ◽

Gas Condensation ◽

Recovery Performance

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The Energy-Saving Optimization of the Organic Heat Transfer Material Heater

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.455-456.284 ◽

2012 ◽

Vol 455-456 ◽

pp. 284-288

Author(s):

Wei Li Gu ◽

Jian Xiang Liu

Keyword(s):

Heat Transfer ◽

Energy Saving ◽

Flue Gas ◽

Theoretical Basis ◽

Operation Management ◽

Exergy Loss ◽

Irreversible Processes ◽

Design Parameters ◽

Gas Temperature

this paper studies the typical irreversible processes such as combustion and heat transfer with temperature difference based on the theory of thermodynamics, analyzes the influencing factors on exergy loss in irreversible processes, on the basis of this analysis, proposes the energy-saving optimization measures on design and operation management of the organic heat transfer material heater, and specially points out that in the design process, objective function can be constructed with the exergy loss as evaluation index to determine the outlet flue gas temperature of furnace and the flue gas temperature, and provides theoretical basis for the determination of design parameters.

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Improving the Boiler Efficiency by Optimizing the Combustion Air

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.787.238 ◽

2015 ◽

Vol 787 ◽

pp. 238-242 ◽

Cited By ~ 2

Author(s):

R. Pachaiyappan ◽

J. Dasa Prakash

Keyword(s):

Heat Transfer ◽

Water Temperature ◽

Steam Generator ◽

Air Temperature ◽

Flue Gas ◽

Maximum Heat ◽

Air Preheater ◽

Hot Air ◽

Boiler Efficiency ◽

Efficient Combustion

Air pre-heater and economizer are heat transfer surfaces in which air temperature and water temperature are raised by transferring heat from other media such as flue gas. Hot air is necessary for rapid combustion in the furnace and also for drying coal in milling plants. So an essential boiler accessory which serves this purpose is air pre-heater. The air pre-heater is not essential for operation of steam generator, but they are used where a study of cost indicates that money can be saved or efficient combustion can be obtained by their use. The decision for its adoption can be made when the financial advantages is weighed against the capital cost of heater. The efficiency of the boiler increases with the increase in the temperature of the combustion air used in the furnace. This is achieved by the increased temperature of the flue gas in the air preheater and economizer zone. This paper deals with the different ways to obtain the maximum heat from the flue gas travelling through the air preheater and the economizer zone to improve the boiler efficiency.

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Investigation of Heat Transfer for Shell-Tube Fuel-Cooled Heat Exchanger

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.378.459 ◽

2013 ◽

Vol 378 ◽

pp. 459-465

Author(s):

Ya Guo Lu ◽

Peng Fei Zhu

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Relative Error ◽

Absolute Error ◽

Heat Transfer Characteristics ◽

Shell Side ◽

Transfer Characteristics ◽

Aero Engine ◽

The Absolute

A calculate method based on ε-NTU model for heat transfer characteristics of shell-tube fuel-cooled heat exchanger of aero-engine lubrication system was built. The heat convection coefficient was obtained by a dimensionless curve (Re~StPr2/3), which was detailed introduced as well. A case study was executed at last. The absolute error of the outlet lubrication of the tube side and the shell side between the value of calculation and experiment was less than ±10°C, and the relative error was less than 6.5%. The absolute error of the heat transferred between calculation and experiment was less than ±0.9kW, and the relative error was less than 7.4%. It indicates that the mothod is available for the investigation of heat transfer characteristics of shell-tube fuel-cooled heat exchanger.

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