The first step in producing eco-friendly biodegradable detergents is the dehydrogenation process of heavy paraffins. Despite its importance, a few studies have been conducted on the process. In this paper, the heavy paraffin dehydrogenation process was elucidated using Computational Fluid Dynamics (CFD) to simulate the performance of a pilot-scale fixed-bed reactor, investigate the effects of key operating parameters (temperature, pressure, LHSV, and H₂/HC ratio), and identify the best operating conditions for maximizing mono-olefin yield and selectivity. The validation of CFD simulation results was performed by comparing them with pilot plant data; The absolute relative deviations were less than 5.5%, indicating the adequacy of the simulation was confirmed. The CFD simulation results showed that the paraffin conversion and mono-olefin yield are higher at a lower Hydrogen-to-Hydrocarbon molar ratio (H2/HC). However, the mono-olefin selectivity is higher at higher H2/HC ratios. Therefore, an H2/HC between 4 and 6 would be suggested as the best condition. Also, the conditions to achieve the best system performance were the temperature between 460 and 470 oC and LHSV of 15 hr-1.

Background: Simulation-based education has become more prominent in recent years. In our university, we have begun to use simulation at various levels in the curriculum. Objectives: We decided to utilize simulation to meet the challenges of teaching medical students in the operating theatre, which have slowly risen over the years at our place of practice. Methods: A total of 120 fi nal year medical students posted to anesthesia were divided into two groups and exposed to two diff erent operating theatre (OT) teaching environments: Group I: Actual OT and group 2: Simulated OT. The performance of the two groups on 25 MCQs was compared using the chi-square test and independent t-test. Results: The chi-square test showed no signifi cant diff erence between the groups in the number of students who passed the test at the end of the posting [ 2 (2, N = 119) = 2. 375, P > 0. 05]. An independent t-test carried out on the test scores showed that the actual OT group (M = 10. 15, SD = 2. 284) performed better than the simulated OT group (M = 9. 04, SD = 2. 528), and it was statistically signifi cant [t (112) = 3. 265, P = 0. 001]. Conclusions: There was no diff erence in terms of pass or fail between the two groups suggesting that OT learning could be simulated. However, the actual OT group had overall better scores statistically. Thus the depth of learning may be better with actual OT teaching, especially because the teaching and learning occur in the real environment. Until further research suggests that simulated OT can replace actual OT learning for undergraduates, we plan to use the simulated OT as a bridge towards actual OT learning.

Sulfur emission from coal combustion presents many environmental problems.The techniques used to reduce the amount of sulfur in coal before combustion, include physical, chemical and biological processes. Biological processes based on degradation of sulfur compounds by microorganisms offer many advantages over the conventional physical and chemical processes.The processes are performed under mild conditions with no harmful reaction products and the value of coal is not affected. In this article the progress achieved to date in biodesulfurization of Tabas coal in pilot plant is reviewed. Effect of particle size and pulp density at constant temperature on coal biodesulfurization investigated in this research. The best results obtained was 45% of pyritic sulfur and 20% of total sulfur in reduction at pulp density of 10% and 0-0.5 mm particle size within 14 days.

In thermal cracking plants, it is desired to apply an optimal temperature profile along the reactor to minimize the operation cost. In this article a simulator is developed by the use of a mathematical model, which describes the static operation of a naphtha thermal cracking pilot plant. The model is used to predict the steady state profiles of the gas temperature and product yields. Using a dynamic programming technique, an optimal temperature profile along the reactor is obtained. The effects of operating variables such as steam to hydrocarbon ratio (S/HC), coil outlet temperature (COT) and feed flow rate on product yield are investigated. pilot plant simulation results are compared with the industrial data and the results indicate that they follow the same trend.