THEORITICAL AND EXPERIMENTAL STUDY OF TOXICITY OF FLUE GASES OF A BURNER WITH COMBINED FLAME FORMATION
Abstract
A convenient and reliable algorithm based on mathematical programming methods is proposed for calculating the chemical composition of flue gases from a hydrocarbon-fueled burner with combined flame formation. The stability of the computational process is ensured by using the equilibrium constant method in order to reduce the dimensionality of the system of governing equations with an appropriate choice of the nomenclature of reagents and base substances. The model considers twenty-two reagents, a significant proportion of which are toxic, and CO, H2, O2 and N2 are selected as base substances. The equilibrium constants are calculated based on an original approximation of the temperature dependence of the heat capacity of all components. The proposed approximation, unlike standard polynomial ones, not only provides physically justified limits in the region of low and high temperatures, but also contains twice as few fitting parameters. A technique for calculating these parameters using known tabular values has been developed. Preliminary testing of the model was performed for individual chemical blocks (nomenclature subsets) by comparing the calculation results with the data obtained using the JANAF chemical calculator. Calculations of toxicity of flue gases of the experimental burner device with formation of a torch by means of an electric arc and supply of superheated steam are performed in the range of operating parameters extended in comparison with the expected operational one. The result is generalized by methods of mathematical programming taking into account the weighted toxicity of flue gases. An estimate of the error of the formula representation of toxicity is performed. An interpolation algorithm is proposed that allows specifying the weighted toxicity of flue gases in the entire range of scenario modeling. The results of computer modeling were compared with the data of technical tests of the experimental burner: their agreement was established within the multiplier of 2, which corresponds to the methodological and instrumental measurement error. The results obtained in the computational experiment allow optimizing the design and operating parameters of innovative burner devices with a combined mechanism of torch formation. Calculations have shown and experimentally confirmed that the supply of superheated steam to the combustion zone homogenizes the flame, equalizes the rate of oxidation of hydrogen and carbon in the oil fuel, thereby reducing emissions of incomplete combustion products and nitrogen oxides. The development is proposed for use in the design, technical testing and fine-tuning of promising burner devices on oil, alcohol and biofuel.
References
1. Anufriev I.S. Eksperimental'noe issledovanie protsessov pri szhiganii zhidkikh uglevodorodov v gorelochnykh ustroystvakh s podachey peregretogo vodyanogo para: diss. … d-ra tekhn. nauk [Experi-mental study of processes during combustion of liquid hydrocarbons in burner devices with the supply of superheated water vapor: dr. of eng. sc. diss.]. Novosibirsk, 2019, 254 p.
2. GOST 27824-2000. Gorelki promyshlennye na zhidkom toplive. Obshchie tekhnicheskie trebovaniya [GOST 27824-2000. Industrial burners on liquid fuel. General technical requirements]. Moscow: Izd-vo standartov, 2002, 12 p.
3. GOST R 57700.37-2021. Komp'yuternye modeli i modelirovanie. TSifrovye dvoyniki izdeliy [GOST R 57700.37-2021. Computer models and modeling. Digital twins of products]. Moscow: Izd-vo standar-tov, 2021, 11 p.
4. Fiziko-khimicheskoe modelirovanie na EVM [Physicochemical modeling on a computer]. Available at: https://studopedia.ru/ 5_119991_fiziko-himicheskoe-modelirovanie-na-evm.html.
5. Alemasov V.E., Tishin A.P., Dregalin A.F. Obshchiy matematicheskiy metod rascheta i issledovaniya goreniya pri vysokoy temperature [General mathematical method for calculating and studying combus-tion at high temperatures], Fizika goreniya i vzryva [Physics of Combustion and Explosion], 1971, Vol. 7, No. 1, pp. 77-84.
6. Belov G.V., Trusov B.G. Termodinamicheskoe modelirovanie khimicheski reagiruyushchikh system [Thermodynamic modeling of chemically reacting systems]. Moscow: Izd-vo MGTU im.
N.E. Baumana, 2013.
7. Belov G. On linear programming approach for the calculation of chemical equilibrium in complex ther-modynamic systems, J. Math. Сhem., 2010, Vol. 47, No. 1, Art. 446. Available at: https://doi.org/10.1007/s10910-009-9580-y.
8. Shchetinkov E.S. Fizika goreniya gazov [Physics of gas combustion]. Moscow: Nauka, 1965, 739 p.
9. Stepanov N.F., Erlykina M.E., Filippov G.G. Metody lineynoy algebry v fizicheskoy khimii [Methods of linear algebra in physical chemistry]. Moscow: Izd-vo MGU, 1976, 360 p.
10. Varnatts Yu., Maas U., Dibbl R. Gorenie: Fizicheskie i khimicheskie aspekty, modelirovanie, eksperi-menty, obrazovanie zagryaznyayushchikh veshchestv [Combustion: physical and chemical aspects, mod-eling, experiments, formation of pollutants]: transl. from engl. Moscow: Fizmatlit, 2003, 352 p.
11. Potapov A.V. Khimicheskoe ravnovesie mnogotemperaturnykh sistem [Chemical equilibrium of mul-titemperature systems], Teplofizika vysokikh temperature [High Temperature Thermophysics], 1966, Vol. 4, No. 1, pp. 55-58.
12. Petrusev A.S. Pereobuslavlivanie khimicheskikh istochnikov v uravneniyakh tipa diffuziya – kon-vektsiya – khimicheskaya kinetika [Preconditioning of chemical sources in diffusion-convection-chemical kinetics equations], Matematicheskoe modelirovanie [Mathematical Modeling], 2019,
Vol. 31, No. 5, pp. 56-68.
13. Son K.E. redutsirovanie polnoy sistemy uravneniy khimicheskoy kinetiki dlya techeniy mnogokompo-nentnykh vysokotemperaturnykh gazov na osnove metoda chastichnogo lokal'nogo ravnovesiya [Reduc-tion of the complete system of chemical kinetics equations for multicomponent high-temperature gas flows based on the partial local equilibrium method], Teplofizika vysokikh temperature [High Tempera-ture Thermal Physics], 2020, Vol. 58, No. 1, pp. 81-90.
14. Govorukhin V.N., Tsibulin V.G. Komp'yuter v matematicheskom issledovanii: Maple, MATLAB,
LaTeX: uchebnyy kurs [Computer in mathematical research: Maple, MATLAB, LaTeX: training course]. Saint Petersburg: "Piter", 2001, 642 p.
15. D'yakonov V.P. Mathcad 8-12 dlya studentov [Mathcad 8-12 for students]. Moscow: Solon-Press, 2005, 588 p.
16. Azimova N.N., Baranichenko V.V., Ladosha E.N. i dr. Algoritm vyyavleniya khimizma i vedushchie khimicheskie reaktsii v gorelkakh, ispol'zuyushchikh uglevodorodnye i spirtovye topliva [Algorithm for identifying chemistry and leading chemical reactions in burners using hydrocarbon and alcohol fuels], Navigator v mire nauki i obrazovaniya [Navigator in the world of science and education], 2023, No. 01 (58)'. Certificate of registration OFERNiO 25103 dated 02/28/2023.
17. Mascitti V.R. A simplified equilibrium hydrocarbon-air combustion gas model for use in air-breathing engine cycle computer programs, NASA TN D-4747, 1968, 47 p.
18. Stull D., Prophet H. JANAF Thermochemical Tables, second edition. National Institute of Standards and Technology, 1971, 1139 p.
19. Gordon S., McBride B.J. Computer Program for Calculation of Complex Chemical Equi-librium Com-positions and Applications: I. Analysis, NASA Reference Publication 1311, 1994.
20. McBride B.J., Gordon S. Computer Program for Calculation of Complex Chemical Equilibrium Compo-sitions and Applications: II. Users Manual and Program Description, NASA Reference Publication 1311, 1996.
