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This paper analyzes the effect of energization on income, education, health and agricultural productivity in the dispersed rural areas of Colombia. For this, the results of the 3rd National Agriculture Census 2014 conducted by the National Administrative Department of Statistics (DANE, for its acronym in Spanish) were used. The sample size of the cross section of the CNA is 1122 municipalities, which includes the Archipelago of San Andrés and Providencia and 20 non-municipalized areas.

The efficiency of combustion in furnaces is the measure of heat released in the flame absorbed by the fluid to be heated and is considered one of the most important variables when conducting studies on processes that occur in continuous process industries. The furnace efficiency is calculated using various mathematical models proposed in the literature; these models vary in complexity depending on the analyzed variables. The models I and II are based on the amount of energy absorbed by the furnace using the heating value, the model III contains variables such as air excess, stack gas temperature and adiabatic flame temperature, meanwhile the model IV contains heating losses in furnace's wall (2%), the stack gas temperature and excess air. In this paper was used computer simulation to evaluate fuel gas mixtures with Lower Heating Values (LHV) between 800 to 2500 Btu/ft³, and they were compared with natural gas and data process; the results show that the combustion characteristics might change by varying the fuel composition. It was also found decreased combustion efficiency due to high hydrogen concentration; on the other hand the adiabatic flame temperature was increased in function of gas composition. Model IV presented in this research allowed evaluating combustion process efficiency using only two variables: stack gas temperature and the excess air. La eficiencia de combustión en hornos es la medida del calor liberado en la llama que es absorbido por el fluido a calentar y es considerada una de las variables más importantes en la realización de estudios de los procesos que ocurren en una planta de proceso continuo. La eficiencia de un horno es calculada usando diferentes modelos matemáticos propuestos en la literatura, los cuales varían en su complejidad dependiendo de las variables analizadas. Los modelos I y II se basan en la cantidad de calor que es absorbida por el equipo fundamentados en el poder calorífico, el modelo III incluye variables como el exceso de aire, temperatura de chimenea y la temperatura adiabática de llama, mientras el modelo IV incluye pérdidas con las paredes del horno del 2%, la temperatura de chimenea y el exceso de aire. Mediante simulación computacional fueron simuladas mezclas de gas combustible con poder calorífico inferior (LHV por sus siglas en inglés) entre 800-2500 BTU/pie³, y se compararon con el gas natural y con datos de proceso; encontrando que las características de la combustión cambian debido a la variación en la composición del combustible. Se presentó baja eficiencia debido a la alta concentración de hidrógeno y un aumento en la temperatura adiabática de llama en función de la composición del gas. Finalmente el modelo IV permitió evaluar la eficiencia del proceso de combustión de forma efectiva, pues solamente utiliza la temperatura de chimenea y el exceso de aire.

Combustion equipments use fuel mixtures with variable composition according to available products. In order to analyze the characteristics of these blends a set of particular cases were simulated using SimSci Pro II ® software. Simulation was applied to find the correlation between process safety problems, combustion efficiency, equipment reliability and service life as a function of fuel composition. It was evident that combustion mode failures are related with High Heating Value (HHV) and fuel density. The impact of changes in the composition mixtures over thermal consumption may be significant and may exceed the limits of specified flame conditions in design standards for boilers and furnaces. In turn, these situations may cause both operational problems and integrity issues for the equipment. The main effects of the variation of calorific value and Wobbe index in the furnaces are evident in the high temperatures of tubes surfaces. There is a direct relationship between the increasing of heating power and the increase of surface temperature at the tubes. This effect causes also overheating in equipments, specially on radiation area; likewise, these conditions affect the burner, which is not designed for these blends, and lead to inefficient combustion, increased gas emissions and higher cost for maintenance due to damage in the structure of the furnace and its associated systems. Different biomass and mixtures of natural and refinery gas used as fuel in furnaces and boilers were compared in scenarios of operational upset, all of them generating combustion inefficiencies, and negative impact on the integrity of equipment.

En este artículo de investigación científica se analiza el efecto del cambio de la composición del gas combustible (Gas de Refinería (GR) por Gas Natural (GN)) sobre las características del proceso combustión en hornos de la industria de refinación del petróleo; se evaluó el poder calorífico, el índice de Wobbe (IW) y exceso de oxígeno, para mezclas combustibles de composición variable. Mediante simulación computacional del proceso de combustión se calculó la temperatura adiabática de llama, eficiencia y la composición de los productos de combustión. Se evaluaron mezclas de gases combustibles con poderes caloríficos entre 800-2500 Btu/pie3 y se compararon con la combustión de gas natural. Se registró variabilidad en la temperatura adiabática y la eficiencia en función de la composición del gas y el exceso de oxígeno, lo que genera inestabilidad en el horno y mayor impacto ambiental. This scientific research article is an analysis of the effect fuel gas composition change (from Refinery Gas to Natural Gas) has on the characteristics of combustion process in industrial oil refining furnaces; heat power, Wobbe Index, and oxygen excess were evaluated for combustible mixtures of variable composition. Through computational simulation of the combustion process, adiabatic temperature of the flame, efficiency, and composition of combustion products were calculated. Mixtures of combustible gases with heat powers between 800 and 2500 Btu/cubic feet were evaluated and compared to natural gas combustion. Variability of adiabatic temperature and efficiency in function of gas composition and oxygen excess occurred; and this resulted in furnace instability and higher environmental impact.