Synergy in the hydrothermal pyrolysis of oil shale/sawdust blends

摘要

Synergy (A) in a co-process is a difference between the actual result and the result calculated by proportional contributions of the components. In this work, A in the yields of hydrothermal pyrolysis products of Estonian oil shale (A) and pine sawdust (B) blends was studied. The effect of the sawdust organic matter fraction (x(B)) in the blend organic matter (0-1 g/g) on the yield of pyrolysis products (i): gas, consecutive extracts with hexane, benzene and tetrahydrofurane, and solid residue was estimated under various water/blend ratios (0-3 g/g), added water density (0-0.5 g/cm(3)), and durations (2-3 h) at nominal temperature 380 degrees C. Equimolar synergy reactions were proved basing on the proportionality between Delta(i) and the product of the fractions of the components in the blend (x(A)x(B)). The coefficients of the proportionality (3), called synergy factors, were estimated for the systems studied. As a rule, positive values of Delta and delta were found in the gas yield and negative in the yield of organic matter remaining in the solid residue. Lack of synergy was evident in the yields of benzene extract and tetrahydrofurane extract in the co-pyrolysis without water and when water density was below 0.3 g/cm(3). An effective synergy was revealed in the yield of benzene extracts under insufficient durations when decomposition of the blend was not completed. (C) 2015 Elsevier B.V. All rights reserved.