Study on the Combustion Characteristics of Oil Shale and Its Semicoke by Using a Thermobalance and a Drop-Tube Furnace

Abstract

The combustion characteristics of Huadian oil shale and its semicoke are comparatively studied using a thermobalance (TB) and a drop-tube furnace (DTF). It is found that the ignition mechanism of oil shale and semicoke is hetero-homogeneous and heterogeneous, respectively. Drop-tube furnace experiments with both oil shale and semicoke show that the carbon (C) conversion proceeds almost simultaneously with the particle burnout, while the hydrogen (H) conversion is faster and that of nitrogen (N) and sulphur (S) slower than the particle burnout. The kinetic behavior of semicoke combustion is analyzed by drop-tube furnace experiments based on the first-order reaction model, and the kinetic model with known pre-exponential factor A a (26.3 g•cm-2 s-1 •atm-1) and apparent active energy E a (65.8 kJ/mol) is obtained.

Microanalysis of Oil Shale of the Leningrad Field

“…In modern conditions of ever-increasing energy consumption, the creation of technologies ensuring the integrated use of fuel raw materials and materials with the maximum reduction of the harmful effects on the environment is becoming more and more relevant. Simultaneously with the increase in demand for traditional energy sources such as oil, gas and coal, there is a steady decline in their capacities, which raises interest in the processing of low-grade hydrocarbon raw materials and the wastes of their thermal processing [1][2][3][4][5][6][7][8][9][10][11][12][13].…”

“…According to the latest estimation, the potential reserves of the oil shale in Russia are huge and the Leningrad deposit is one of the largest oil shale deposits in Russia: А+В+С1 = 925.4 million tones, C2 = 309.6 million tones, non-commercial -11.8 million tones. This deposit is situated Leningrad, Pskov and Novgorod regions being the part of the Baltic basin [1][2][3][4][5].…”

Influence of Temperature on the Total Surface Area of Nanopores of Leningrad Deposits Oil Shale

“…The main method of oil shale processing, which holds a unique position among low-grade raw materials, is thermal processing and currently an extensive experience has been accumulated in this area (processes: Haloter, Enefit Estonia; Alberta Tasiuk, Australia; Petrosik, Brazil; Fushun, China; Lurgi-Rurgaz, Germany; Union, USA and others). After processing oil shale, a large quantity of solid ash waste is formed (up to 50wt% of the initial shale); its storage consumes enormous areas [1][2][3][4][5][6][7][8][9][10][11][12].…”

“…One of the largest Baltic basin deposits is located in the Leningrad field, Russian Federation: A + B + C1 = 925.4 million tons, C2 = 309.6 million tons, off-balance -11.8 million tons. Large reserves of these raw materials and annually growing energy consumption indicate a need to solve the problems associated with their processing [1][2][3][4][5][6][7][8][9][10]. Based on the above, the purpose of this work was to study the changes in the total surface area of pores (nano, micro) and the total porosity of oil shale resulting from thermal exposure.…”