A novel hybrid approach of activated carbon and ultrasound cavitation for the intensification of palm oil mill effluent (POME) polishing

This investigation focuses on activated carbon (AC) adsorption and ultrasound (US) cavitation for polishing the palm oil mill effluent (POME). Both AC adsorption and US cavitation were investigated individually, in series and operating them in a combined way. The efficiency of above processes has been evaluated in terms of removal of chemical oxygen demand (COD) and total suspended solids (TSS). For the individual operation, the optimisation studies were carried out by using the following conditions: AC dosage (50–200 g/L); contact time (2, 4, 6 h); US power amplitude (50% and 80%) and US cavitation time (30–180 min). The optimisation studies utilising US power amplitude (50%) and cavitation time (15 min) followed by AC adsorption using minimum AC dosage (50 g/L) and contact time (30 min) resulted in ∼100% COD and 83.33% TSS removals which meets the discharge limits set by the Department of Environment (DoE), Malaysia. The hybrid operation was also studied by simultaneously employing AC adsorption and US cavitation and it was observed that an adsorption dosage of 50 g/L resulted into achieving 73.08% COD and 98.33% TSS removals within 15 min of US irradiation. With the possibility of continuous and feasible sonochemical reactors, this hybrid approach of US cavitation followed by AC adsorption could be an alternative processing technique for POME polishing

Numerical investigation of boiling and forced convection heat transfer in inclined porous enclosure using modified enthalpy formulation

Two-Phase flow in an inclined rectangular porous media, under unsteady-state condition, has been numerically investigated in this article, based on the modified h-formulation of Two-Phase Mixture Model (TPMM). The governing equations have been discretised using Finite Volume Method (FVM) and solved iteratively in a SIMPLE-like manner. Effects of various parameters on the flow and temperature fields have been investigated, which clearly demonstrated that the inclination angle strongly affect the boiling initiation. Recirculating flow has been observed when the inclination angle θ>0˚. The results clearly indicated that the operating conditions and the porous medium properties have significant effects on the initiation and termination of phase change process. A closer inspection of the results reveals that the presence of a critical inclination angle depending on the value of K* and, Re1 which correspond to a maximum values of vapour volume. The modified h-formulation requires significantly less computational time as compared with the existing H-formulation of TPMM

Combined magnetic field and adsorption process for treatment of biologically treated palm oil mill effluent (POME)

The production of palm oil, however, results in the generation of large quantities of polluted wastewater commonly referred as palm oil mill effluent (POME). There is an actual need to seek factors intensifying the treatment processes of POME. The new methods which not required extension of existing plants or building very expensive bioreactors are still searching. In recent years increasing attention has been directed to the possibility of improvement of waste water treatment by static magnetic field. The aim of our study was to determine the impact of constant magnetic field as well as the integration of this technique with the famous technique used for wastewater treatment which is adsorption by activated carbon as a novel method for POME treatment. This new method has been found to be a useful method for removing colour, TSS and COD from biologically treated POME. (C) 2014 Elsevier B.V. All rights reserved

Numerical investigation of boiling and forced convection heat transfer in inclined porous enclosure using modified enthalpy formulation

Two-Phase flow in an inclined rectangular porous media, under unsteady-state condition, has been numerically investigated in this article, based on the modified h-formulation of Two-Phase Mixture Model (TPMM). The governing equations have been discretised using Finite Volume Method (FVM) and solved iteratively in a SIMPLE-like manner. Effects of various parameters on the flow and temperature fields have been investigated, which clearly demonstrated that the inclination angle strongly affect the boiling initiation. Recirculating flow has been observed when the inclination angle θ>0˚. The results clearly indicated that the operating conditions and the porous medium properties have significant effects on the initiation and termination of phase change process. A closer inspection of the results reveals that the presence of a critical inclination angle depending on the value of K* and, Re1 which correspond to a maximum values of vapour volume. The modified h-formulation requires significantly less computational time as compared with the existing H-formulation of TPMM