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The flow behaviors of two-dimensional (2D) wet monodisperse and poly disperse foams are investigated by the quasi-static simulation. We set the same inlet velocity on the cross section of the foam channel and then focus on the elastic-plastic deformation of the 2D wet foam according to the strain caused by the foam flow. The gas fraction in foam is referred to as foam quality and the effects of foam quality on the shear modulus, bubble dynamics, and stress-strain properties are obtained by the simulation. In the elastic domain, the shear modulus of monodisperse foam decreases exponentially with foam quality, but for the polydisperse foam, the shear modulus tends to increase. The shear banding of the polydisperse foam appears in the low strain and disappears gradually as the strain and foam quality increase. We adopt shear rate to represent the change rate of average bubbles displacements versus y-coordinates and find that the distribution of shear rate in the y-direction changes with iteration. Additionally, energy of the foam is stored and dissipated with the elastic-plastic deformation of the foam. The average shear stress generated by the foam structure and the initial increment of normal stress difference caused by the elastic deformation increase with the increase of foam quality. [ABSTRACT FROM AUTHOR]

The supercritical water oxidation (SCWO) technology has shown high efficiency in Lurgi coal gasification wastewater treatment. However, the cost of oxygen and energy consumption become the major limiting factors for the industrial operation as the oxygen used is always excessive. In this paper, we proposed two schemes that combined the SCWO and gasification processes to recover the excessive oxygen and heat. The combined processes were simulated by Aspen Plus software and their economic values were also analyzed. In scheme (I), the SCWO and gasification processes were combined by a pressure reducer. The depressurized SCWO effluent was directly used as a gasification agent. In this scheme, zero wastewater discharge can be realized and all the excessive oxygen and heat were completely recovered. In scheme (II), the SCWO and gasification processes were combined by a heat exchanger. The heat of the SCWO effluent was recovered through the heat exchange with another introduced cold fluid. The oxygen was recovered in the oxygen recovery section set behind the SCWO process, in which a byproduct of industrial grade liquefied CO2 was produced. The recovery efficiencies of oxygen and heat were 99.35% and 90.76%, respectively. For a single gasifier with steam of 27 t h-1 (673.15 K) and oxygen of 6.73 t h-1 (373.15 K) as gasification agents, the investment in scheme (I) and scheme (II) were 8500 and 103500 €, respectively, and the recovered profit of materials and heat were 730 and 691 € h-1, respectively [ABSTRACT FROM AUTHOR]