As far the classical EIS technique is studied the systems which are exited step to step with an external perturbation signals and at the different frequencies, therefore, the main disadvantage of this method in correlate to this approach is the length of the measurement. Also, it can be mentioned that this method only can give information concerning the electrochemical process of materials before and after process. For example, for evaluated the undergoing corrosion process of a system we only can give information about the system after and before the corrosion process and in the condition that the system is in a stable
Therefore, it could be argued when comparing and contrasting the two approaches, it is crucial to look at the advantages and disadvantages of the two. The main advantages of the experimental method is the ability to control what each participant experiences and this allows researchers to test precise and accurate hypotheses and draw conclusions about how one variable affects another. The main disadvantage of is that it cannot replicate or reproduce the complexity of real life and it can miss social rules and other factors that could establish whether a bystander intervenes or not. The discourse analysis, on the other hand can capture a richer and more varied picture of people’s experiences and looks at people’s actual experiences. However, it cannot provide general rules about human behaviour that could be applied to more than one
Abstract - A robot/system capable of operating in active pipelines would be of great commercial and industrial benefit. Pipe inspection is necessary to locate defects due to corrosion and wear while the pipe is transporting fluids. Because pipelines are typically buried underground, they are in contact with the soil and subject to corrosion, where the steel pipe wall oxidizes, and effectively reducing wall thickness. Recently many plants' pipes and drains became old and many robots to inspect these pipes were developed in the past. Inspection robots are used in many fields of industry.
Although it was preferable to avoid pipeline burial due to the length of time it can take for re-colonisation by marine species it was considered necessary to bury Pipeline A. Pipes A and B are both made of high quality corrosion resistant material, able to withstand high pressure and will be protected against upheaval buckling in order to avoid pipeline rupture which may result in oil spills. Although crossings of pipelines should be avoided if possible it was necessary in this case. Both pipes were laid as perpendicular to the existing pipe and separated by a distance mutually agreed by both pipe owners. All exclusion zones on approach to the BLP were taken into account in order to avoid damage to the pipeline or facility, or injury to
Chapter 1 Introduction 1.1. Ethylene & Propylene Demand and Supply Ethylene is a key building block in the petrochemical industry due to its application as raw material for intermediate base chemicals, such as polyethylene, ethylene oxide, and styrene. These base chemicals are applied in innumerable consumer products. Approximately 60% of the world ethylene demand is required for the production of polyethylene. The primary use of polyethylene is in plastic films for packaging and all kind of bags.
There are various simulation programs used in industry depending on the field, application and desired simulation products such as for entire process unit or one piece of equipment. Aspen can be a very powerful tool when used to its full capabilities for a Chemical Engineer in a different of fields including oil and gas production, refining, chemical processing, environmental studies and power generation (Bernards and Overney, 2004). The advantages of modelling using by Aspen plus are it can reduce plant design as well as allows designer to quickly test various plant configurations. Besides, it also helps in improve current process as determines optimal process conditions within given constraints and assists in locating the constraining parts of a process that will be carried out using model analysis tools such as sensitvity analysis and optimization tool. Furthermore, the use of a process flowsheet simulator is beneficial in research and development (R&D), design and production.
A corrosion allowance of 2mm was also considered. INTRODUCTION Tanks are an important part of the oil and gas industry. They are used for storing crude oil as well as the refined products of crude oil. The state of refined products of crude oil is highly unstable in harsh weather conditions. With the high demand for products of crude oil, it is therefore important to ensure a safe process for refining, transporting as well its storage.
3. Modeling and Numerical Simulation Method Experimental methods have been used to find which design of a radiator or HEX is economic and efficient. However, because of the high cost and the complexity of experiments, a numerical method is adopted in the present work to analyze the performance of HEXs. The physical model of the HEX has to be simplified and certain assumptions have to be set up. Meanwhile the governing equations and corresponding boundary conditions are introduced for the simulation model.
However, this modelingmethod is quite complex for the controller design, because it requires a huge amount of computation and simplifications. Empirical modeling method The empirical modeling utilizes the input and output data from the operation of the column to build the relationship between the input and the output. This method is also known as “Black box modeling” because inner dynamics are not considered. With this type ofmodelling, the understanding of the inner dynamics of the column does not required. So, the computation can be reduced.
One of the unit operation in chemical engineering is fractional distillation. In the chemical process industries, fractionating columns are widely used where large quantities of liquids have to be distilled. Some of the examples of industries which involve fractional distillation are the petroleum processing, petrochemical production, natural gas processing, coal tar processing, brewing, liquified air separation, and hydrocarbon solvents production. Apart from all these processes, fractional distillation has the widest application in petroleum refineries. In such refineries, the crude oil feedstock is a complex, multicomponent mixture that must be separated, and yields of pure chemical compounds are not expected, only groups of compounds within a relatively small range of boiling points, also called fractions.