Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : semi


Characterizations of Semi-Silica Refractory Bricks Produced from Local Iraqi Materials

Mohammed H. Al-Taie; Alaa H. Ali; Abeer F. Al-Attar

Engineering and Technology Journal, 2014, Volume 32, Issue 9, Pages 2268-2276

This research was carried out to investigate the suitability of locally white sand and Dwaikhla clay (Kaolin) for manufacture of semi-silica refractory bricks as thermal insulators for lining the furnaces. Preliminary investigations had been done to determine the physical, chemical, thermal and mechanical properties with mineralogical constitution of raw materials by XRD analysis. Different amounts of kaolinite were added as binder to the white sand (raw materials) of semi-silica bricks. The specimens molded according to DIN standards by using semi-dry pressing method at pressure of (24.516MPa) according to the DIN1068 standards. After drying process at 110°C the specimens fired at firing temperatures (1000, 1100, 1200, 1300 and 1400) °C. The fired specimens have been investigated to determination the physical properties including bulk density, porosity, and the mechanical properties including compressive strength and thermal properties including thermal conductivity. It has been observed from the results that local white sand and kaolinite could be used as possible source raw materials for manufacture semi-silica refractories, mainly required for glass, ceramics factory in Rammadi.

Kinematic Analysis of Semi-Flexible Robot

Muhsin J. Jweeg; Hussein M. Al-Khafaji

Engineering and Technology Journal, 2012, Volume 30, Issue 13, Pages 2265-2284

In this work, a kinematic model of semi- flexible robot with two degrees of
freedom based on the joint angles and arm’s deflections is presented with taking in
consideration the small deflection parameter (exact model), and used experimental
deformation results to make a comparison between the approximate model and the
exact model. Due to the difficulties of using flexible robot in the real live, a two
degrees semi-flexible robot was built; this robot will be used to get the experimental
results for comparison. The comparison shows a small difference between the
approximate model and the exact model, so with increasing the flexibility this
difference will increase and in some applications of robot this difference will be
significant and worth to take in consideration.

Dynamic Simulation of Semi-Batch Catalytic Distillation Used for Esterfication Reaction

Ziadoon M. Shakor; Khalid A. Sukkar

Engineering and Technology Journal, 2008, Volume 26, Issue 7, Pages 777-796

In this paper the detailed mathematical dynamic model of semi-batch reactive
distillation is formulated for ethyl acetate synthesis (estrefication reaction).
The model is composed of material balance, heat balance, and equilibrium
equations. The set of nonlinear ordinary differential equations governing the
unsteady state composition profile in a semi-batch reactive distillation column
were solved by using fourth order Runge-Kutta integration method with the aid of
the powerful MATLAB 6.5 program which used to simulate and optimize the
semi-batch reactive distillation column.
The simulation provides compositions, temperatures and holdups profiles
along the column as a function of time. Also the reactant conversion and ethyl
acetate purity in distillate are calculated.
Finally, the simulation results are analyzed to find the optimum operating
policy of reflux ratio, Ethanol/Acetic acid and catalyst weight.