Effect of Toluene Addition on Hydrogen Sulfide Combustion Under Claus Condition

2013 ◽  
Author(s):  
Salisu Ibrahim ◽  
Ahmed S. AlShoaibi ◽  
Ashwani K. Gupta
Keyword(s):  
Hydrogen Sulfide ◽  
Flame Temperature ◽  
Reactor Performance ◽  
Heating Value ◽  
Toluene Concentration ◽  
Maximum Value ◽  
Baseline Case ◽  
Claus Reactor ◽  
Large Heating ◽  
Sulfur Capture

Experimental results on the effect of different amounts of toluene addition to H2S gas stream are presented. Three toluene concentrations of 0.5%, 1% and 5% in H2S are presented and compared with the baseline case of 100% H2S/air combustion. Temperature data showed that addition of toluene to H2S gas stream increases the flame temperature because of large heating value associated with toluene. Addition of toluene resulted in the production of H2, which increased with increase in the amounts of toluene addition. Furthermore, increased addition of toluene concentration increased the asymptotic value of hydrogen sulfide due to oxidation competition between the formed H2 and H2S. The results also showed that the presence of CO triggers the formation of COS with toluene addition due to reaction of CO with SO2. The results revealed that SO2 mole fraction increased to a maximum value then decayed with distance along the reactor. Addition of toluene increased the rate of SO2 decay. These results have direct impact on sulfur capture in Claus reactor performance for sulfur capture.

Xylene Addition Effects in Thermal Stage of Claus Reactors

2014 ◽  
Author(s):  
Salisu Ibrahim ◽  
Ahmed S. AlShoaibi ◽  
Ashwani K. Gupta
Keyword(s):  
Mole Fraction ◽  
Elemental Sulfur ◽  
Formation Rate ◽  
Direct Impact ◽  
Reactor Performance ◽  
Complete Combustion ◽  
Baseline Case ◽  
Claus Reactor ◽  
Sulfur Radicals

Experimental results are presented on the effect of xylene addition to H2S/O2 flames at equivalence ratio of 3.0 (Claus Condition) with respect to H2S and complete combustion of xylene. The results from the combustion of H2S/xylene mixture is compared with the baseline case of 100% H2S combustion to isolate the role of xylene addition in the Claus reactor. Combustion of H2S alone showed a decrease in its mole until it reached to an asymptotic minimum mole fraction value. This resulted in the formation of SO2 to a maximum mole fraction which subsequently decomposed from the formation of elemental sulfur through its reaction with H2S. Addition of small amount of xylene (0.5% and 1%) increased the asymptotic minimum value of H2S as well as the formation of H2 which provided oxidation competition between the formed H2 and H2S. Presence of xylene also triggered the formation of CH4 and CO which provided pathway on the formation of COS and CS2. The oxidation of CH4 and CO by SO2 and other sulfur radicals reduced the maximum mole fraction of SO2 but increased the subsequent rate of SO2 decomposition to increase the formation rate of elemental sulfur. These results show the direct impact of trace amounts of xylene in the feed stream on sulfur formation to reveal direct impact on the Claus reactor performance for sulfur capture.

scholarly journals ESTIMATIVA DA TEMPERATURA ADIABÁTICA DE CHAMA DA FORNALHA DE UMA CALDEIRA SIDERÚRGICA INDUSTRIAL

e-xacta ◽  
2016 ◽  
Vol 9 (2) ◽  
Author(s):  
Letícia Fabri Turetta ◽  
Andréa Oliveira Souza da Costa
Keyword(s):  
Flame Temperature ◽  
Operating Conditions ◽  
Adiabatic Temperature ◽  
Heating Value ◽  
Fuel Feed ◽  
Lower Heating Value ◽  
Thermoelectric Plant ◽  
Industrial Boiler ◽  
By Products ◽  
Lower Heating

<p>A indústria siderúrgica produz quatro subprodutos com significativa capacidade de geração de energia. Esses subprodutos podem ser utilizados como combustível na caldeira siderúrgica, equipamento da central termoelétrica. O objetivo deste estudo é propor uma modelagem para estimar a temperatura adiabática da chama da fornalha de uma caldeira siderúrgica com a variação de ar e combustível disponível. A técnica empregada consiste no princípio da Primeira Lei da Termodinâmica. O balanço de energia do sistema foi proposto definindo assim o modelo. A solução do modelo possibilita estimar a temperatura adiabática do sistema. Na indústria, a temperatura adiabática é determinada pelo poder calorífico inferior dos combustíveis. A metodologia proposta neste estudo faz com que não sejam necessários levantamentos experimentais do poder calorífico inferior. Os valores da temperatura adiabática simulados indicam que utilizar condições operacionais distintas na alimentação do combustível e do ar podem afetar significativamente o valor deste parâmetro. Nas simulação com a variação de ar, nota-se que a temperatura adiabática decresce com o acréscimo do excesso de ar. Tal resultado é esperado, uma vez que o aumento da massa, contida no sistema, diminui a eficiência energética do processo. Conclui-se que a metodologia proposta provou ser eficaz de descrever o sistema quando diferentes condições de alimentação são adotadas.</p><p> </p><p>ABSTRACT</p>Steel industry produces four by-products with significant capacity of energy generation. These products can be used as fuel at steel boiler, equipment thermoelectric plant. The objective of this study is to propose a modeling to estimate the adiabatic flame temperature furnace’s of an industrial boiler steelmaking with the variation of available air and fuel. The technique employed consists in principle of the First Law of Thermodynamics. The system's energy balance was proposed thus defining the model. The solution’s model enables to estimate the system’s  temperature of the adiabatic. In industry, the adiabatic temperature is determined by the fuel’s lower heating value. The methodology proposed in this study makes is not necessary experimental surveys of the lower heating value. The values at the adiabatic temperature simulated to indicate that use different operating conditions in the feed of fuel and air can significantly affect the value of this parameter. In the simulation with the variation in air, it is noted that the adiabatic temperature decreases with the increase of excess air. This result is expected since the increase of the mass contained in the system decreases the energy efficiency of the process. It is concluded that the methodology proved to be effective to describe the system when different air and fuel feed are adopted.

A Comparative CFD Simulation Study of Two-Channel and Three-Channel Claus Reactors

2017 ◽  
Author(s):  
Shan Huang ◽  
Qulan Zhou ◽  
Na Li ◽  
Fangyong Tian ◽  
Lisheng Zhang
Keyword(s):  
Hydrogen Sulfide ◽  
Channel Model ◽  
Flow Fields ◽  
Elementary Sulfur ◽  
Channel Reactor ◽  
Sulfur Recovery ◽  
Acid Gas ◽  
Gas Channel ◽  
Claus Reactor ◽  
Air Channel

The Claus reactors is widely used to recover elementary sulfur from hydrogen sulfide that is contained in fresh natural gas. It involves thermal oxidation of hydrogen sulfide and its reaction with sulfur dioxide to form sulfur and water vapor. To improve the efficiency of the process, we built two kinds of 3-dimensional Claus reactor models to explore the key factors that affect the combustion reactions. The two-channel Claus reactor consisted of an air channel and an acid gas channel (60% H2S, 33% CO2, 7%H2O) while the three-channel Claus reactor consisted of two air channels and an acid gas channel (60% H2S, 33% CO2, 7%H2O). The two-channel model was built according to the devices used in the factory while the three-channel model was improved by us from the two-channel model. In both the two models, air and acid gas turned into swirling flow in their channels respectively before their mixture. Then air and acid gas mixed and burned at the throat of the models. The most remarkable difference between the two kinds of Claus reactors was that the three-channel reactor had an additional inner air channel inside the acid gas channel that can be helpful to the mix of the acid gas and air. The second difference was that the two kinds of reactors had different deflectors to swirl in the flow fields. In this study, we compared the flow fields and concentration fields of the two kinds of Claus reactors by using a computational fluid dynamics (CFD) tool. The simulation results indicated that the swirling intensity and the mix intensity played an important role in the combustion reactions. The efficiency of sulfur recovery in Claus reactors increased with an increase of the swirling intensity or the mix intensity. The stronger the swirling intensity or the mix intensity was, the sooner the mixture of air and acid gas reached to the best stoichiometric ratio. The three-channel reactor had a better performance than that of the two-channel reactor due to the additional inner air channel which can strengthen the mix of the acid gas and air from the inside of the acid gas. Moreover, the helix deflectors in the three-channel reactor had a better swirling performance than that of the vane deflectors in the two-channel reactor. From the comparison of the two models, we can obtain a way to improve the process of elementary sulfur recovery in the industry, which can be helpful to reduce pollution emissions and improve economic performance.

Numerical Simulation of Turbulent Biogas Combustion

2007 ◽  
Author(s):  
Beibei Yan ◽  
Xuesong Bai ◽  
Guanyi Chen ◽  
Changye Liu
Keyword(s):  
Numerical Simulation ◽  
Mass Flow ◽  
Flame Temperature ◽  
Combustion Process ◽  
Methane Combustion ◽  
Operational Parameters ◽  
Heating Value ◽  
Air Supply ◽  
Methane Flame ◽  
Secondary Air

Operating parameters are considered important for the biogas combustion process and the resulted flame features. The paper investigated the influence of typical parameters through numerical simulation, which include the dimension of combustor, fuel and air mass flow, and secondary air supply. The results from the simulations show that the biogas combustion behaves, to some extent, similarly to the methane combustion, yet significant differences exist between their flames. The combustion process is fairly sensitive to the geometrical and operational parameters. Biogas flame temperature is even lower compared to the methane flame temperature because biogas contains CO2 resulting in low heating value, therefore it is not straightforward to obtain stable combustion. Preheated secondary air or reduced its mass flow may have to be used in this case.

scholarly journals Effects of Lemongrass Oil as Fuel in Diesel Engine

2020 ◽  
Vol 12 (4) ◽  
pp. 63-70
Author(s):  
Nageswara Rao GANGOLU ◽  
Radha Krishna GOPIDESI ◽  
Immadi Mehar ANUDEEP
Keyword(s):  
Diesel Engine ◽  
Diesel Fuel ◽  
Flame Temperature ◽  
The Other ◽  
Brake Thermal Efficiency ◽  
Heating Value ◽  
Maximum Reduction ◽  
Lower Heating Value ◽  
Lemongrass Oil ◽  
Lower Heating

The rapid increase of diesel engines and diminishing of diesel fuel creates a challenge for researchers to find alternative fuel. The present experiment is performed on a 3.5 kW diesel engine. Here, diesel is replaced with pure lemongrass oil (LGO) of10%, 20%, and 30% by volume with diesel. The obtained data from the experimental work may exhibit the Brake Thermal Efficiency (BTE) of LG20 equivalent to pure diesel. The specific fuel consumption (SFC) of LGO blends shows an increase compared to diesel, due to the lower heating value for LGO blends. On the other hand, LGO blends show lower emissions of NOX, due to the lower peak flame temperature. When compared to the other samples, the LG30 gives a maximum reduction in NOX emissions; of 10.33%. When compared to biodiesel blends, diesel fuel shows a significant increase in the Net Heat Release rate (NHR).

scholarly journals Design of a Simple Pyrolysis Reactor for Plastic Waste Conversion into Liquid Fuel using Biomass as Heating Source

Eksergi ◽  
2020 ◽  
Vol 17 (1) ◽  
pp. 1
Author(s):  
Aditya Kurniawan ◽  
Bambang Sugiarto ◽  
Andri Perdana
Keyword(s):  
Liquid Fuel ◽  
Liquid Product ◽  
Reaction System ◽  
Combustion Efficiency ◽  
Plastic Waste ◽  
Heating Value ◽  
Heating Source ◽  
Average Temperature ◽  
Maximum Value ◽  
Cooling Media

A design that emphasizes simplicity and cost-effectiveness is applied to the plastic pyrolysis reaction system to produce liquid fuel. The reactor is fabricated from the waste refrigerant tank. The energy source for pyrolysis is generated by the combustion of biomass pellets. Forced convection by an electric blower is utilized to enhance the combustion efficiency and thus increase the heating rate with the overall average temperature at 412 °C. The coiled pipe is employed as a condenser system with water as its cooling media. The quantity of liquid product is measured for a different mass of PET-type plastic waste feed, with a maximum value of 17.7% w/w of feed mass is obtained. The physical characteristic of the liquid product is then analyzed using standard methods. It is found that its characteristics have approached the specification of commercial liquid fuel in the domestic market, with a liquid specific gravity of 0.776 and a heating value of 46 MJ/kg.

Influence of the Air Preheat Temperature and the Fuel Preheat Temperature in the Adiabatic Flame Temperature for Gaseous Fuels of Low Heating Value

2012 ◽  
Author(s):  
A. Tourlidakis ◽  
A. Malkogianni
Keyword(s):  
Nitrogen Oxides ◽  
Thermal Stresses ◽  
Flame Temperature ◽  
Calorific Value ◽  
Combustible Mixture ◽  
Combustion System ◽  
Preheat Temperature ◽  
Heating Value ◽  
Adiabatic Flame Temperature ◽  
Gaseous Fuels

Adiabatic flame temperature is of significant importance for the design of a GT combustor, as it is the temperature under the condition of no heat loss takes place from the combustion system. This importance arises from the fact that it plays an important role in the pollutants emitted from the system, such as carbon oxides and nitrogen oxides. Additionally, the temperature also affect the thermal stresses set up in the combustion system, such stress may lead to the deterioration of the chamber if not well controlled. Consequently, it is essential before the construction of the combustion chamber, a simulation process for the temperature distribution within the combustion system to be carried out, in order to avoid local thermal stresses and to minimize nitrogen oxides and carbon dioxides emissions, pollutants of great concern, that are very dependent on the flame temperature. The factors that predominantly affect the adiabatic flame temperature are the fuel heating value, the type of oxidant, FAR, the temperature of the reactants, the amount of oxygen in the air, as well as the dissociation phenomena. In this study, a code in FORTRAN programming language is developed for the calculation of the adiabatic flame temperature. The simulation is performed for different gaseous fuels of low calorific value, for air preheat, for fuel preheat, as well as for various Φ. From the simulation resulted that Tad and Φ for each fuel are totally dependent on the fuel’s calorific value. Both for the case of the air preheat, and the fuel preheat temperature it was observed increase of the Tad. Preheating of combustible mixture by recycling heat from flue gases has been considered an effective technology not only for combustion of low calorific fuels but also for fuel conservation.

scholarly journals Can hydrogen enriched biogas be used as domestic fuel? - Part I – Thermal Characteristics of Blended Biogas/H2 Impinging Flames

2021 ◽  
Vol 28 (2) ◽  
pp. 60-67
Author(s):  
Yi Chen ◽  
Udaya Kahangamage ◽  
Quan Zhou ◽  
Chun Wah Leung
Keyword(s):  
Heat Flux ◽  
Reynolds Number ◽  
Equivalence Ratio ◽  
Fossil Fuels ◽  
Flame Temperature ◽  
Thermal Characteristics ◽  
Pollutant Emission ◽  
Heating Value ◽  
Flux Profile ◽  
H2 Addition

Biogas is a renewable energy source widely produced by breakdowns of organic matters in natural environment and industry. However, it is not yet an ideal replacement of fossil fuels because its high CO2 content would deteriorate its thermal performance. To upgrade biogas for possible domestic application, hydrogen enrichment is proposed by adding high-grade hydrogen (H2) to biogas in order to improve its flammability and heating value, and reduce pollutant emission. However, most previous studies on blended Biogas/H2 focus on analysing the effects of H2 fraction and nozzle-to-plate distance on the heat flux profile and flame temperature. No comprehensive study has ever demonstrated the influence of the Reynolds number and equivalence ratio under a wide operating range. In this study, a test rig was built to investigate the effects of the Reynolds number and equivalence ratio on heat flux and thermal efficiency of blended biogas/H2 impinging flame. The blended biogas/H2 consisted of 80% biogas and 20% H2 addition in volume. Biogas was artificially made by 60% CH4 and 40% CO2 (BG60). The Reynolds number ranges from 300 to 1500 and equivalence ratio ranges from 1 to 3. A comparative study was also conducted between pure biogas (BG60) and biogas with 20% H2 enrichment.

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