Mathematical Modelling of Viscosity of Liquids with Respect to Oil Refining - Case Study Example

NAME: xxx INSTITUTION: xxx UNIT CODE: xxx UNIT NAME: xxx TITLE: MATHEMATICAL MODELLING OF VISCOSITY OF LIQUIDS WITH RESPECT TO OIL REFINING LECTURE: xxx ©2017 Table of Contents 1.Introduction 1 2.Block Diagram 2 2.1Complex distillation 4 2.2Vacuum distillation 4 2.3Delayed coking process 4 2.4Fluid coking process 5 2.5Fluid catalytic cracking 6 3.Mathematical modelling 7 Conclusion 8 References 10 1. Introduction Unprocessed crude oil is not generally used in industrial applications due to its relatively high viscosity. However, numerous hydrocarbon molecules in crude oil are separated in a refinery into components that can be more readily used in industrial applications, such as fuels, lubricants ad raw materials in manufacturing. Oil refining refers to the chemical processes and other facilities used in oil refineries to transform crude oil into useful products such as gasoline, petrol, jet fuel, and liquefied petroleum gas. The refinery process results in products with varying physical and chemical properties, making crude oil vastly useful in wide range of applications. Petroleum products are usually grouped into four categories, namely;- Lights distillates – These are the lightest products and are usually very volatile, such as gasoline, naphtha and LPG Middle distillates – These products are heavier in mass than the light distillates, and are generally in liquid state. They include kerosene, jet fuel and diesel Heavy distillates Residuum – These are products that are found at the base of the refining process, and are usually a viscous liquid or in a semi- solid state. They include heavy fuel oils, asphalt, wax and lubricating oils The above classification exhibits the significant role that viscosity plays in the oil refining process, with less viscous products having more industrial uses, and as such are more in demand than the more viscous products. Cost advantages exist from churning out products with the specified characteristics the first time they are run through the refining process, rather than trying to blend them further along [Kas12]. Mathematical modelling of the viscosity of the various products of the oil refining process can be an efficient tool to help in the optimization of the processes to result in a more economically profitable distribution of the petroleum products. 2. Block Diagram Figure 1: Oil refining block diagram[Pne12] The processes applied in the refinery of oil are as follows;- 2.1 Complex distillation This refers to the process of distilling and separating the valuable distillates, such as naphtha and kerosene, from the crude feedstock. The crude oil is preheated, then desalted and dehydrated using electrostatic enhanced liquid/ liquid separation. The crude oil is then heated again to the desired temperature and flashed in the atmospheric distillation column separating into the various products that are collected at the top, sides and bottom of the refining chamber. Table 1: Typical yields of the complex distillation process PRODUCT Yield, (% weight of crude) Disposition Light ends 2.3 LPG Light Naphtha 6.3 Naphtha Hydroheating Medium Naphtha 14.4 Naphtha Hydroheating Heavy Naphtha 9.4 Distillate Hydroheating Kerosene 9.9 Distillate Hydroheating Atmospheric Gas Oil 15.1 Fluid Catalytic Cracking Reduced Crude 42.6 Vacuum Distillation Unit 2.2 Vacuum distillation This refers to the process of reducing the hydrocarbon partial pressure via vacuum and stripping steam, to recover valuable gas oils from crude oil. The crude oil is heated to the desired temperature and flashed in the vacuum distillation column. Pump-around cooling loops are used to create internal liquid refluxes, with the products collected at the top, sides and bottom of the chamber. Table 2: Typical yields of the vacuum distillation process PRODUCT Yield, (% weight of crude) Disposition Light ends Read More

Table 1: Typical yields of the complex distillation process PRODUCT Yield, (% weight of crude) Disposition Light ends 2.3 LPG Light Naphtha 6.3 Naphtha Hydroheating Medium Naphtha 14.4 Naphtha Hydroheating Heavy Naphtha 9.4 Distillate Hydroheating Kerosene 9.9 Distillate Hydroheating Atmospheric Gas Oil 15.1 Fluid Catalytic Cracking Reduced Crude 42.6 Vacuum Distillation Unit 2.2 Vacuum distillation This refers to the process of reducing the hydrocarbon partial pressure via vacuum and stripping steam, to recover valuable gas oils from crude oil.

The crude oil is heated to the desired temperature and flashed in the vacuum distillation column. Pump-around cooling loops are used to create internal liquid refluxes, with the products collected at the top, sides and bottom of the chamber. Table 2: Typical yields of the vacuum distillation process PRODUCT Yield, (% weight of crude) Disposition Light ends

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