Advanced Materials Research Vol. 1113

Abstract: Distillation is the primary separation process widely used in the industrial chemical process. Although it has many advantages, the main drawback is its large energy requirement, which may significantly influence the overall plant profitability. However, the large energy requirement of these processes can be systematically reduced by using driving force and energy integration methods. This paper presents a methodology for designing energy efficient distillation columns systems based on those two methods. Generally, the proposed methodology consists of four hierarchical steps. In the first step, the system of distillation columns for multicomponent separation is designed based on the conventional distillation column design (shortcut) method. Then, the conventional distillation columns systems design is improved in terms of energy saving by using driving force method in the second step. It is expected in the third step that the distillation columns systems design can be further improved in terms of energy saving by using energy integration method. Finally, the distillation columns systems design is evaluated in terms of economic performance. The simulation results by using Aspen HYSYS have shown that the driving force sequence by using shortcut method for NGLs has energy savings with 55% reduction compared to a direct method with shortcut method. It can be verified that the proposed methodology has the capability in designing energy efficient distillation columns in an easy, systematic and practical manners.

Abstract: The continued using of petroleum energy as a sourced for fuel is widely recognized as unsustainable because of the decreasing of supplies while increasing of the demand. Therefore, it becomes a global agenda to develop a renewable, sustainable and alternative fuel to meets with all the demand. Thus, biodiesel seems to be one of the best choices. In Malaysia, the biodiesel used is from edible vegetable oil sources; palm oil. The uses of palm oil as biodiesel production source have been concern because of the competition with food materials. In this study, various types of biodiesel feedstock are being studied and compared with diesel. The purpose of this comparison is to obtain the optimum engine performance of these different types of biodiesel (edible, non-edible, waste cooking oil) on which are more suitable to be used as alternative fuel. The optimum engine performance effect can be obtains by considering the Brake Power (BP), Specific Fuel Consumption (SFC), Exhaust Gas Temperature (EGT) and Brake Thermal Efficiency (BTE).

Abstract: Essential oil contained volatile compounds and they are benefit in many fields such as pharmaceutical, flavor, perfume, food, agriculture, and detergent. However, its inadequate volatile characteristics made it less efficient. Many microencapsulation methods were conducted for varies essential oils. The choice of microencapsulation method very much affected by the material to be encapsulated, wall material and its application. This review paper highlighted on microencapsulation methods of volatiles essential oils and the basic release characteristic of the active ingredients from the capsules.

Abstract: This study aims to directly analyze the production of hydrogen and methane gas from POME via high frequency ultrasonication atomization. The advantage of the currently common process was studied in regards to the application of low frequency ultrasonic pretreatment prior to biological processes; anaerobic digestion and fermentation for the production of methane and hydrogen gases respectively. Existing ultrasonic application is limited to sludge disintegration, reducing chemical oxygen demand (COD) values and total solid, while subsequent biological processes take several days to produce gases. However, in this study, high frequency (2.4 MHz) ultrasonic atomization process was able to produce methane and hydrogen gases directly without any biological process. These gases were detected by using an online gas chromatography. The results from the ultrasonication process show that the production gases are consisted majorly of hydrogen compared to methane. Thus, high frequency ultrasonication process can be considered as an alternative method in rapid production of methane and hydrogen gases.

Abstract: This article is an overview of the use of polymer gelled technology to improve sweep efficiency in enhanced oil recovery. Recent progress use polymer types, Polyacrylamide and polysaccharide to be applied in enhanced oil recovery (EOR). A lot of researchers concluded that polymer gel stability must be maintained to ensure excellent performance in sweep efficiency. The application of polymer gels in permeability modification to improve volumetric sweep efficiency of fluid injection processes showed fruitful efforts as it can be a potential candidate to enhance oil recovery as compared to other technologies.

Abstract: Carbon dioxide (CO2) is a major greenhouse gas that contributes to the global warming due to rise in temperature of the earth's atmosphere. Industrial activities such as fossil fuel combustion and production of several chemicals become one of the major contributors to CO2 emissions. This issue can be solved by providing improved technology to mitigate the carbon dioxide emissions. Absorption of CO2 in aqueous solution has been used extensively and has been proven to be the most applicable technology for CO2 capture. The effectiveness of absorption process is strongly depending on its hydrodynamic and mass transfer characteristics. Development of model is required to predict the behavior of the CO2 absorption process for reliable design and operation. In this paper, a review of the empirical models that have been implemented in CO2 absorption over a last decade is presented. The details of each model are discussed and compared.

Abstract: Dihydroxystearic acid (DHSA) is perceived to be of significant value to various types of industries, especially the oleochemical industry. It is produced by reacting palm-based crude oleic acid (OA) with formic acid and hydrogen peroxide through the in situ epoxidation-dihydroxylation, a multistep reaction process. Optimization of the reaction’s operating conditions with respect to the selectivity of DHSA was conducted via the Taguchi method of optimization. The selectivity of DHSA was determined based on gas chromatography (GC) analysis. The signal-to-noise (S/N) ratio analysis procedure in Taguchi method revealed that the optimum operating conditions for the production of crude DHSA with respect to its selectivity were found to be: catalyst (sulphuric acid) loading at 0.5 gm, formic acid-to-oleic acid unsaturation mole ratio of 1:1, hydrogen peroxide-to-oleic acid unsaturation mole ratio of 0.75:1 and reaction temperature: 85°C. ANOVA tested at 90% confidence level revealed that reaction temperature and catalyst loading highly affect the selectivity of DHSA. The selectivity of DHSA was improved to 97.2% by applying the optimum operating conditions as obtained by Taguchi method.

Abstract: Earlier works have proved the potentials of altering the vapor liquid equilibrium of azeotropic mixture by sonication phenomena. In this work a mathematical model of a single stage vapor-liquid equilibrium system developed in Aspen Custom Modeler is exported to Aspen Plus to represent one stage of ultrasonic flash distillation (USF). The USF modules are connected serially to mimic a distillation process. As a case study, the separation of ethanol-ethyl acetate mixture is considered. The final targeted composition of 99 mole % of ethyl acetate was achieved when 27 USF modules were used despite the fact that the mixture form azeotrope at 55 mole % ethyl acetate. The results reinforced the anticipated potentials of sonication phenomena in intensifying distillation process to overcome azeotropes, and provide useful insights for the development of a pilot-scaled facility that is currently under development.

Abstract: This paper presents the performances of an enhanced fuzzy logic controller (EFLC) for simulated Heat Exchanger (HE) temperature control system. The HE system is modeled mathematically using Energy Balance Equation and simulated using MATLAB/Simulink software. The Fuzzy Inference Structure (FIS) used was Sugeno-type. EFLC comprises of two parts which are normalized FLC part and model reference (MR) part. Both normalized and MRFLC part was using Gaussian membership function (MF) with 7x7 rule bases. Set Point (SP) tests conducted for change from 43°C to 39°C, 39°C to 35°C and 43°C to 35°C. The performances on SP tests of the FLC and proposed EFLC were compared to PID controller. The results showed that EFLC produced lower decay ratio (DR) with less oscillations, reduced undershoot (US), shorter settling time (T_s) and minimum Integral Absoluter Error (IAE) compare to FLC and PID controller.

Abstract: The aim of this research is to develop an inherent safety assessment technique for research and development stage of chemical process design through the application of logistic function. There are many current inherent safety assessment methods that are index-based. Alternative process synthesis routes to the desired product are ranked based on the total index value, which is calculated by assigning scoring numbers to process safety hazard parameters. Such approach is not sufficed to fully understand the hazards posed by each process routes as the exact cause of the hazards is unknown to the users. The technique proposed in this research will show not only the total scores and the ranks of the evaluated processes but also provide users with more detailed data on the chemical and operational properties that posed the maximum hazards to the process called the root-cause analysis. Root-cause analysis is done through graphical representation constructed from the logistic functions.