Most dyes are by nature recalcitrant. An initial dye biodegradation study indicates that given the right process conditions, colour due to azo dyes can be removed biologically from wastewater. Biodegradation has been found to proceed via cleavage of azo bond(s). Anoxic condition was found to be necessary for biological colour removal. The removal rate was faster in the presence of a readily biodegradable co-substrate.

Pilot plant study on ultrafiltration of Palm Oil Mill Effluent (POME) was performed at United Plantation Palm Oil Mill, Jenderata Estate, Perak, Malaysia. Industrial thin channel DDS35-2.25 was utilized to house two kinds of membranes, polysulfone GR61P and skinned polyamide membranes. Long term flux decline and method of cleaning the membranes were investigated. The experiments were design to study a three stage ultrafiltration process which involved three different concentration. The concentration in each stage was determined by considering the minimum membrane area required for a five fold increase in concentration at the final stage. Unless stated the experiments were performed at 60 °C and a pressure of about 1. 2 bars.

The feasibility of using ultrafiltration processes to treat ground water was shown in a study where aerated and unaerated water was ultrafiltered using a Memtec membrane cartridge Permeate from aerated samples produced water of a quality within WHO drinking water standard. Ultrafiltration flux was at a reasonable level of 45 – 60 kg/m2 h and 60 – 80 kg/m2 h when pressures were at 35 and 70 kPa respectively. A new ground water treatment system was proposed where ultrafiltration membranes were employed to separate the solids from water after aeration.

This paper is a study on the mechanism of moisture movement in concrete. The influence and effect of several factors are discussed. The suitability of a few flow models to the moisture movement in concrete was investigated. Several investigations to be taken into account in the formulation of the moisture flow model in concrete are made.

Reactions between NO and char were investigated in a fluidised bed reactor in the presence of SO2. The reaction between NO and char is enhanced in the presence of SO2. NO conversion was found to increase by about 50 to 100% when 1250 p.p.m. SO2 were present in the fluidising gas mixture. The products of the reactions are CO/CO2 and N2 with the CO/CO2 ratio decreasing as the SO2 concentration is increased. The SO2 concentration was found to be unaffected by the NO/char reaction.

The Cho Shui river Basin is the second largest basin of Taiwan. To conduct the optimum water resources, utilization study for the basin daily flow data are developed using mainly two models e.g. the HYSIM (Hydrologic Simulation Model), and Tank Model. Both models applied are of rainfall runoff type. The HYSIM model has been applied to ten gauged sites, which is calibrated for short period of record and then daily flow data for 28-years are developed. During calibration more weight age is given on low flows. Tank model latest version is applied to four basins out of the ten. It is observed from the statistical comparison and matching of hydrographs that the results from the HYSIM model are better than that of Tank Model in those four stations.

The unsaturated flow equation in one dimension has been solved using two types of techniques. The first technique involves the solving of the partial differential equation for flow in rigid unsaturated porous media using implicit finite difference approach. The second technique is based on step function model and is solved by developing the Green and Ampt approach. Both techniques are used to calculate the amount of water drained from initially saturated profile to a moving water table.

The Green and Ampt approach was developed for the falling water table case following an initial sudden drop in the position of the water table. The analysis presents an approximate solution for one-dimensional flow in saturated porous media. The formulation is based on calculating the position of draining front with time and the cumulative outflow time relationships for stratified profile. The Green and Ampt results are checked by using data obtained from a well-proven computer-based numerical solution for unsaturated flow equation involving an implicit finite difference approach.