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Low grade waste heat utilizat ion and new combustion technology are challenging tasks for researchers to achieve these objectives. This paper is concerned with the integration of coal gasification system with a comb ined gas turbine, steam turbine power plant cycles and with ammon ia-water cycle, wh ich is known as Kalina cycle. A l-maghara coal in North Sinai is used as the solid fuel in gasification process.Three cycles configurationsare compared as follows: Scheme (A) with dual pressure Heat recovery boiler with the condenser of steam cycle as the evaporator for Kalina cycle,scheme (B) with heat recovery boiler for both of steam and Kalina cycleand scheme (C), similar to scheme (A), but with a superheating in Kalina cycleto identify the most promising one for implementation. Key parameters of Kalina cycle were the main elements of comparison. Results revealed that scheme (A) has the best performance with regard to the output power, thermal efficiency and specific fuel consumption. Substantially, the integration of Kalina cycle with coal gasification comb ined cycle counterbalances the reduction of the overall efficiency due to the gasification thermal efficiency. Therefore, integration of Kalina cycle in the IC GCC is justified.Furthermo re, part load calculations were made fo r scheme (A) and identified that the integration of Kalina cycle to ICGCC imposed restrictions to Kalina cycle constrains, so that it is more economical to keep such configuration of combined plants at nearly full load conditions.

Developing accurate models for pressure drop in slurry pipelines is one of the most important challenges of researchers around the world. Pressure drop is one of the most important technical parameters to be ev aluated by the designer of pipeline slurry transportation system. Also it is the parameter which dictates the selection of pump capacity. The properties of slurries mainly depend on the tendency of the particles to settle out from the carrying liquid. The extent to which the particles will be free to settle in horizontal flow depends on the terminal velocity, the turbulence and particleparticle interaction. Physical models for the prediction of the pressure drop, flow regime, and specific energy consumption are presented. Several studies for pressure drop prediction in slurry flow are available in literature. The comparison between the proposed correlations with the experimental data of the settling slurries is satisfactory. Since the decrease of the specific power consumption and increase overall the transport system efficiency, the carrying capacity should be increased. The experimental investigations were performed on three different sorts of sand solids to satisfy the economic advantage by adjusting the particle size. The experiments were conducted in 26.8 mm inner diameter horizontal pipe on three sizes of sand particles of which mean diameter are 0.2 mm (fine), 0.7 mm (medium) and 1.4 mm (coarse). Flow velocity was up to 7 m/s and overall concentration up to 33% by volume for each velocity. The effect of slurry velocity and particle concentration on the slurry flow behaviour and pressure drop in the turbulent regime was evaluated.

Water desalination became very important process because of the leakage in clean water sources and the increase of human demand. This paper introduces an experimental study for air gab membrane desalination process AGMD using low pressure membrane type. The experimental unit was designed and fabricated according to the data collected from the literature review. The unit used experimentally is a