Design and operation of chemical plants involves a combination of synthesis, analysis and evaluation of alternatives. Suchactivitieshave traditionallybeendrivenbyeconomic factorsfirst, followedbyengineering, safety and environmental considerations. Recently, chemical companies have embraced the concept of sustainable development, entailing renewable feedmaterials and energy, non-toxic and biode...

For the high utilization of abundant lignocellulose, which is difficult to directly convert into ethanol, an energy-efficient ethanol production process using acetic acid was examined, and its energy saving performance, economics, and thermodynamic efficiency were compared with the conventional process. The raw ethanol synthesized from acetic acid and hydrogen was fed to the proposed ethanol co...

In this paper we developed an analytical solution for a mathematical model of an air dehumidification process. This solution has good accuracy when compared with reliable experimental data available in the literature. The present study was confined to the cases with the mass flow rate of desiccant solution being much greater than the minimum required by the equilibrium calculation, so that the ...

A gradient free optimization-simulationmethod for processesmodelledwith the simulator AspenHYSYS is developed. The tool is based on a Tabu Search (TS) and the Nelder-Mead Downhill Simplex (NMDS) method. The local optima that result from the TS are fine-tuned with NMDS to reduce the required number of simulations. The tool has been applied to find the total refrigerant flow rate, composition and...

During transportation, there will be vaporization of LNG producing boil-off gas (BOG) and its re-liquefaction is required considering that large volume of BOG to be vented out. A cryogenic refrigeration cycle is utilized in order to re-liquefy the BOG and returns it to the cargo tank. Kapitza and claude are the usually used LNG re-liquefaction cycles. The developments in the processes adopted f...

−An industrial scale hexane process is designed for the implementation of a fully thermally coupled distillation column (FTCDC). A semi-rigorous material balance and Peng-Robinson equilibrium relation are utilized in the structural design. The operational design is conducted with a commercial design program, the HYSYS. The design outcome of the structural design indicates it to be comparable wi...

A computer simulator is written to optimize the conditions of oil and gas separators using Hysys and Matlab software. Off gases in some wellhead equipment of south of Iran are burnt in flare. In the present paper, the separators of one of these wellheads are simulated. By changing different variables such as the plus fraction splitting methods and the temperature of separators the condition wit...