Evaluation of combustion models for determination of refinery furnaces efficiency (original) (raw)
Related papers
2015
Modeling of heat and mass transfer of fired heaters for refinery use was carried out to determine the equipment efficiency as well as the process and flue gas temperature variations. Previous research involving non-computational fluid dynamics (CFD) analysis of fired heaters modeled individual sections of the heater with little attention to the other. In this study, transfer models were developed and compiled in the MATLAB environment for validation. Upon which, simulations were run to determine the most influential parameters affecting the performance of fired heaters. Research papers referenced in this study developed models by incorporating correlations established in the early 1950s’. This study differs in a sense that the formulas used to develop the model are generally modified using common engineering sense to accommodate the dimensions of a refinery fired heater. Initially, the research involved the modeling of separate sections of the heater encompassing heat and mass balan...
Comparative Study with Numerical Simulation of Fossil Fuels Combustion for Industrial Furnaces
International Journal for Research in Applied Science and Engineering Technology, 2017
The selection of liquid or gas fuel to be used in an industrial furnace can be of extreme importance, having a direct effect on its performance, of the equipment. These factors are highly dependent on the combustion process and on factors such as the flame shape droplet path, temperature variation and heat flux distributions within the furnace. In the present work, numerical simulations were carried out, using the finite volume method, with the purpose of analyzing and comparing the combustion process inside a furnace when operating with three types of fuel: Pentane, Hexane and Heptane all are reacting with air with different mass flow rate and air velocity. The results will be showing the temperature distribution, droplet profiles, and mass fraction of emissions. Liquid fuels or high hydrocarbon have a great advantages over other low carbon fuels because they are in liquid form so that they are easily vaporized in combustion process and there is no need for compressing the fuels. Simulation results shows that Heptane fuel has released great amount of energy and high temperature profile as compare to other liquid fuels. Emission after the combustion process is lowest in high hydrocarbon fuel because of rapid evaporation and high combustible in nature.
Chinese Journal of Chemical Engineering, 2009
This numerical study investigates the effects of using a diluted fuel (50% natural gas and 50% N 2 ) in an industrial furnace under several cases of conventional combustion (air with 21% O 2 at 300 and 1273 K) and the highly preheated and diluted air (1273 K with 10% O 2 and 90% N 2 ) combustion (HPDAC) conditions using an in-house computer program. It was found that by applying a combined diluted fuel and oxidant instead of their uncombined and/or undiluted states, the best condition is obtained for the establishment of HPDAC's main unique features. These features are low mean and maximum gas temperature and high radiation/total heat transfer to gas and tubes; as well as more uniformity of theirs distributions which results in decrease in NO x pollutant formation and increase in furnace efficiency or energy saving. Moreover, a variety of chemical flame shape, the process fluid and tubes walls temperatures profiles, the required regenerator efficiency and finally the concentration and velocity patterns have been also qualitatively/quantitatively studied.
2018
Due to the depletion of non-renewable natural resources, the increase in the emission of pollutants and the growing global energy demand, it is increasingly important to implement strategies that lead to a sustainable use of available resources and to improve the efficiency of the processes currently employed; A tool widely used for this purpose is the exergy analysis. Currently, refining processes use refinery gases as the main source of energy, which consist of mixtures of natural gas and residual gases; these are obtained as by-products in different processing units, so their composition varies according to the process they come from, highlighting their content of gases such as ethylene, hydrogen, propane and propylene. In this order of ideas, in this work we evaluated the effect of the variation of the proportion of residual gas (propane) with respect to natural gas, on the thermodynamic behaviour of combustion in a refinery furnace; through the methodology of exergy analysis. T...
Efficiency Estimation of Olefin Furnaces in Order to Provide Methods for Increasing the Efficiency
2019
Despite the growing trend in the petrochemical industry in the country, the industry has faced challenges and accomplishments. One of the most important challenges in the petrochemical industry is energy management in the refinery. Fajr Jam refinery is designed to refine part of sour gas produced from Phase 6 of South Pars gas field in Iran and the nominal capacity of gas refining at this site, to determine the factors affecting energy consumption in the ophthalmic furnaces, 104 and 109 kilns were selected and the following were monitored scientifically: monitoring of furnace wall temperature with thermography, furnace feed analysis, steak gas analysis and energy efficiency of furnaces. The results of this study showed that in the furnace 104, the design efficiency and real efficiency was 92.98 and 84.67, respectively and for the furnace 109, the design efficiency and real efficiency was 94.98 and 71.18, respectively. As a result, the amount of energy loss is high and should save en...
Companies that require gaseous fuel that burns in their processes, show concern for the reduction of emissions of greenhouse gases, at present, 69 % of the greenhouse gases produced by the burning of the refining processes and petrochemicals, which also generated a significant environmental impact, it shows a good performance as the world leader in the field of sustainability, as measured by the Dow Jones sustainability index, which evaluates companies in economic, environmental and social. The parameters and operating conditions for the ovens are affected by the composition of fuel gas, which may be a mixture of natural gas and process gas containing methane, ethane, propane and hydrogen. The process instability due to changes in gas composition represents a risk to industrial safety, environmental issues and structural damage due to high temperatures. In order to study this problem, the baseline emission of CO2 generated was collected in ovens; CO2 historical data of the process is analyzed and the relationship established with calorific value which depended on the composition of the gas. The statistical analysis of the results and the simulation of the combustion process, determined that CO2 values have a tendency to increase when using fuels of high calorific value, which should regulate the use of mixtures containing compounds such as ethane and ethylene.
THE MODELLING OF THE EFFECT OF AIR FUEL RATIO ON UNBURNED HYDROCARBONS FOR MILD COMBUSTION
ABSTRACT Unburned hydrocarbons (UHC) are a waste and pollution to the environment. UHC will happen when rich combustion occurred. In the case of exhaust gas recirculation (EGR) utilized to diluted the oxidiser, UHC in the EGR can result in unwanted combustion at unwanted locations (ie in the EGR pipe). FLUENT was utilised to model the open furnace. The volume flow rate for air and fuel was the main parameter of the study.
Thermodynamic analysis of heat and mass transfer in the combustion chamber of an industrial furnace
Strojarstvo
CFD analysis of heavy fuel oil combustion in a 6.7 MW cylindrical vertically- fired furnace has been carried out. The furnace supplies process heat in the Oil refinery of the National oil company (INA) in Rijeka-Croatia. The motivation of the work was to improve the performance of the combustion process by changing fuel and burner parameters. The commercial CFD-code Fluent is used to model transport and reaction in the furnace. The chosen CFD models for heavy fuel oil spray combustion are compared with measurement data found in the literature and good agreement is achieved. The combustion process is investigated through the influence of different parameters: air excess ratio, fuel oil droplet diameter, spray cone half-angle and burner swirl number. It is determined that the best performance of the combustion process is achieved for an air excess ratio of 1.15. The droplet diameter should be neither too small nor too large: medium-sized droplets (~100 μm) mix well with air and reside...
Determination of the Gas Composition Effect in Carbon Dioxide Emission at Refinery Furnaces
Chemical Engineering Transactions, 2013
Companies that require gaseous fuel that burns in their processes, show concern for the reduction of emissions of greenhouse gases, at present, 69 % of the greenhouse gases produced by the burning of the refining processes and petrochemicals, which also generated a significant environmental impact, it shows a good performance as the world leader in the field of sustainability, as measured by the Dow Jones sustainability index, which evaluates companies in economic, environmental and social. The parameters and operating conditions for the ovens are affected by the composition of fuel gas, which may be a mixture of natural gas and process gas containing methane, ethane, propane and hydrogen. The process instability due to changes in gas composition represents a risk to industrial safety, environmental issues and structural damage due to high temperatures. In order to study this problem, the baseline emission of CO2 generated was collected in ovens; CO2 historical data of the process i...
Study on Combustion Performances of Burners in Furnace in Coal Fired Power Plants
Steam generation are one of the critical components of a thermal powerplant. Studies of the performance of combustion in a steam generator are very complex in nature. In this work numerical simulations are used to investigate the characteristics of gas and coal particle two-phase flow in boiler furnaces. In order to examine the detailed behavior of the flow different load conditions were given with varying the velocity of flow of air and fuel. Flow characteristics with multiple number of burners and firing at different locations resembeling variation of load is studied. Studies of effect of different operating conditions are studied using commercial code FLUENT. To determine velocity, temperature characteristics a 3D combustor model isused in this case study. Change of size in burners is done in order to find the temperature profiles changes in furnace. Analyses of particle trajectories are done so as to study the emission characteristics, fouling on burners etc.