Search

There are many old oil wells in Indonesia which are no longer operated by the state-owned oil company Pertamina. Those wells have no longer a sufficient amount of oil to be extracted continuously. One such oil field is located in Wonocolo district, Bojonegoro in East Java Province. Local miners are allowed to operate oil mining by using very simple equipment. Currently, there are around 235 wells. Each well produces 300 to 350 barrels of crude oil per day and was operated two times a week. The crude was sold to Pertamina, but some of the crudes were processed by the miners by using a traditional distillation system called pawon. At least there are 190 pawon in the Wonocolo district. The crude is processed into diesel oil. The oil is sold to the market with a price of IDR 2,750. It is almost half of the price of the regular diesel oil sold by Pertamina, IDR 5,500 per liter. The objective of this study is to increase the quality of traditional diesel oil by applying simple blending operations. To achieve this objective, diesel oils produced by different pawon are treated as feedstock with different grades. Traditional diesel oil is divided into 3 (three) grades based on its density. To obtain the Cetane Index value, the density and the distillation profile of diesel oil is needed. The ASTM D1298 ASTM D86 methods were used to obtain the density and distillation profile of the diesel oil. Cetane Index calculation was carried out by using ASTM D976 and ASTM D4737. Blending is the process of mixing from several ingredients to obtain a new product which is in accordance with the desired specifications. Volume comparisons of blending can affect the quantity and quality of new products produced. The purpose of this study is to obtain the optimal condition of the Index of traditional diesel oil blended. The calculation results of the Cetane Index ASTM D976 are 50.66, 47.59, and 45.24 for Grade 1, Grade 2, and Grade 3, respectively. The calculation results of the Cetane Index ASTM D4737 are 47.04, 45.08, and 43.47 for Grade 1, Grade 2, and Grade 3, respectively. This information can be used to optimize the quality of the traditional diesel oil by diesel blending optimization. The optimization was carried out by applying response surface methods with design of experiment of three component mixture, i.e., the three grades of diesel oil. Determination of optimal conditions The Cetana Index was performed by using Design Expert software with Simplex Lattice Design with Mixture Design method. The optimum results were found and can increase the profit up to 66%. [ABSTRACT FROM AUTHOR]

This review provides information about processing pathways in utilizing oil palm empty fruit bunch (EFB) for the syntheses of various high value bio-products. It analyses different models that have been formulated for optimization purposes which have considered economic value of the products, associated environmental impacts and important compositions of EFB. The latter is due to the fact that EFB has varied for its compositions, depending on several factors but mainly on the origins of the palm oil fruits. The models presented here have a definite set of setbacks and strengths. Each reviewed model explains the reasons for its modeling routes and the advantages that along come with it. [ABSTRACT FROM AUTHOR]

Fired Heaters are easily the most energy-extensive units in process industry. Often times, the operating cost of Fired Heaters can amount to almost 20-50% of a total plant's operating cost. Monitoring the efficiency of these heaters and continuous improvement in design are critical. Significant advancements have been made in simulating the temperature distribution inside Fired-Heaters. This paper focuses on simulating the temperature distribution inside the Radiant Section of a Fired-Heater using the Long-Furnace model; a more accurate extension of the Lobo-Evans method widely accepted in industry. A novel mathematical model is developed and is being construed for application to a Fired-Heater in a Syrian Refinery. The model is potentially more accurate than the Lobo-Evans method and computationally less extensive than a CFD approach. [ABSTRACT FROM AUTHOR]

One of the most important components of a Plug-In Hybrid Electric Vehicle (PHEV) is the battery pack. A large battery pack will allow the car to travel in charge-sustaining mode for a longer period of time, thereby reducing fuel consumption. However, a large pack will result in a high capital and operating cost. In this paper, the optimal number of batteries for the PHEV is determined. The vehicle model was developed using Autonomie and the optimization algorithm was carried out using the actual vehicle model. Due to the large computational time of the problem, the optimization was also executed using an empirical model. Comparisons are provided between the two approaches in terms of accuracy and computational time. [ABSTRACT FROM AUTHOR]

This paper presents models for the calculations of the costs involved and the general material balances during the conversion of the biomass into the final products. These models deal primarily with the conversion processes through thermochemical processing of biomass including gasification, combustion and pyrolysis. The models were developed in the MATLAB environment, all with Graphic User Interface (GUI), meaning that they interact with the user through windows and dialogs instead of through user-input commands. The user only needs to insert values in the model inputs and click a button or two, and the models will be able to generate the results. The developed models can save time and cost to understand and design biomass utilizing systems that deal with thermochemical routes. [ABSTRACT FROM AUTHOR]

Cyclones are the most widely used industrial dust collecting devices for removing particulate matter from air streams. In this work, a new optimization model of multiple cyclone arrangement is presented using General Algebraic Modeling System (GAMS) software in obtaining the optimal number and dimensions of the cyclone, and the best cyclone arrangement for a certain condition with respect to the minimum total cost, including the operating cost and the capital cost. The proposed model of nonlinear programming (NLP) and mixed integer nonlinear programming (MINLP) has been successfully applied to different case studies. The NLP model is applied to an NPK (Nitrogen, Phosphorus, and Potassium) fertilizer plant to find the optimal number and dimensions of the 1D3D, 2D2D, and 1D2D cyclones arranged either in parallel or series. In another case study, the best cyclone arrangement of parallel-series for three different combinations of the 1D3D and 2D2D cyclone is obtained through the use of MINLP modeling. The results show that each type of cyclone (i.e., 1D3D, 2D2D, and 1D2D) has an alternative that can be arranged either in parallel or in series configuration with different optimal numbers of cyclones. Furthermore, in the parallel-series arrangement, the cyclone of 2D2D+2D2D is found to be more economical and efficient compared to the others. [ABSTRACT FROM AUTHOR]

The objective of this study is to develop robust statistical models that can be used to predict the flexural properties and specific gravity of wheat straw polypropylene composite (WSPPC). Constrained mixture design methodology is applied to design a set of optimum experimental design with a three-component mixture: low-impact polypropylene (polymer matrix), ground wheat straw (natural fiber filler) and maleic acid grafted polypropylene as a coupling agent. The D-optimality criteria, the leverage values of design points and Fraction of Design Space graph are used to evaluate the design of experiment. The structural property models of WSPPC are then constructed by analyzing the obtained data and applying fitting model technique of least square regression and backward model term reduction. Unlike some previous similar works on statistical modeling of natural plant fiber thermoplastic composite, this work provides not only the summary of the Analysis of Variance (ANOVA) test, but also provides complete diagnostics case statistic reports which can be used to properly describe the model predictions to meet the standard properties of response surface models. [ABSTRACT FROM AUTHOR]