Natural Gas Plants - Research Paper Example

Plant Introduction As the world is progressing different types of things are required by the population. New advancements are being done in all the sectors of this world. With the increasing requirements of the world today it is seen that many types of materials are being processed. The basic materials for usage for many materials are derived from raw materials. For the processing of these raw materials into something productive, plants have been designed. These plants use different sorts of devices and techniques to furnish the raw materials. All over the world many chemical, water and gas plants have been designed to fulfill the needs of the population. Natural gas is also known to be a necessity of this world. Gas in its pure form is of no particular use to the human beings but after being furnished in a Natural Gas Plant it can be used for several purposes. In some parts of the world it is used as a purpose of fuel and in some parts of the world it is used to light fire. Natural Gas Plants use different processes through which they can produce the sort of gas required by the individuals. It is seen that raw form of gas needs to pass through different stages to produce the productive gas. The processes respectively are known as Removal of Oil and Condensed particles, removal of water, separation of the gas liquids and lastly the removal of carbon dioxide and sulfur from the gas. Gas Plants use Low Temperature Separator, Liquid and Solid desiccant dehydrators, and Fractionators. This report would further revolve around Gas Processing Plants and would provide with further details about it. Objectives Natural Gas Plants use different devices to filter out the natural gas into productive forms. This report would revolve around the two main components of natural gas production which are Fractionators and Liquid and Solid Desiccant dehydrators. Both these components are used by almost all the gas plants to effectively produce the right form of gases. Fractionators use the different boiling points of hydrocarbons to their advantage whereas the dehydrators use different solutions which have the power to absorb and adsorb. The different processes in purifying gas would also be described in this report with emphasis on the two main components. This report would present with findings about the natural gas plants as a whole and not specifically about certain plants (Scott et al 1999) Discussion Gas in its pure form consists of many impurities which need to be filtered by the gas plants so that the gas can be used by the consumers. Gas can be found in oil wells, gas wells and condensate wells. Gas is usually found in a dissolved form of oil which needs to be separated at first. Here the role of Low Temperature Separator comes as it is used to cool the gas and oil. It is then that the oil and condensates are separated from the gas to obtain a better form of the gas. In the next step water is removed from natural gas which can be achieved through the processes of absorption and adsorption. It is in the process of the removal of water that a liquid desiccant dehydrator is used primarily to absorb water vapor from the steam. Glycol is used in the dehydrator which acts as a absorbing agent for water. Pure glycol is not used in the process but rather a solution of it known as diethylene glycol is used. The dehydrator contains a contactor through which the gas is passed. The contactor contains the glycol solution which absorbs water from the gas steam and gets heavy. Here water is completely removed from the gas steam. The glycol solution can be reused through the processes of boiling as water has a low boiling point than that of the glycol solution. Solid desiccant dehydrator also uses almost the same techniques as the liquid desiccant dehydrator. It consists of adsorption towers which have a material known as activated alumina or granular silica gel. As wet gas is passed in these towers water from the gas is adsorbed into the gel or alumina. By adsorption it is meant that the gas settles in the particles which are kept in the dehydrator. This adsorption process helps in retrieving dehydrated gas from the end of the tower. The dehydrator can be used again with same material by passing a heated gas through the tower which would absorb the water vapor of the material (Jon Steiner; A Course in Natural Gas Plant Operations 1976). After these processes the natural gas has to be further filtered out to produce different natural gas liquids which can be productive. This is achieved through the absorption method and the cryogenic expander method. After the natural gas liquids are acquired it is necessary that they are broken down into smaller particles which can be useful. It is here that a fractionator comes into use to separate the natural gas liquids. The fractionator works with different boiling points of hydrocarbons. Fractionator consists of a condenser a pump, a reflux drum and a boiler for gases. Natural gas is first passed through the boiler which has different outlets for different gases. The boiler has different temperatures at different points which is the main help for the fractionators. A Deethanizer helps to separate ethane from the steam at the temperature of -89C. In the next step Depropanizer helps to separate propane from the steam at the temperature of -42C. Then a Debutanizer helps to acquire butane at the temperature of -0.5C. Lastly a Deisobutanizer is used to separate the isomers of butane from normal butane. The fractionators are arranged in such a way that the lightest of the hydrocarbon is boiled first. After the gas is removed it is passed through a condenser which would stable the temperature of the gases which are being acquired. In the final step of the purification of gas the removal of gases like carbon dioxide is necessary. In the final step sulfur and carbon dioxide are removed from the gas steam. These are poisonous compounds which should be removed before being used by the consumers because they can harm the consumers. In the last process amine solution is used to remove sulfur from the natural gas so that it is not poisonous anymore. Amine solution absorbs the sulfur in the gas and makes it pure. The solutions containing amine which are used are monoethanolamine and diethanolamine. The sulfur which is eliminated from the gas can be further used for other purposes. Sulfur itself is a highly priced compound which can be used for sale in the market. Some solid desiccants are also used to remove carbon dioxide and sulfur in some plants (Scott et al 1999; Jon Steiner) Conclusion Natural Gas Plants are present in many parts of the world and the processes mentioned above are used by almost all the plants in this world. It is seen that modern techniques are arising in these plants which would further help to lower down their costs. With modern machineries the process of fractionators and dehydrators can be reduced. However till date the components mentioned above are still being used in natural gas plants. Fractionators and dehydrators are important components which have been described previously and without these important components it is almost impossible to produce pure gas. References Dehydration of Natural Gas by Prof. Jon Steiner Gudmundsson, Norwegian University of Science and Technology Top of Form A Course in Natural Gas Plant Operations. Calgary: Southern Alberta Institute of Technology, 1976. Print. Top of Form Skorupsky, Scott, David Villafana, and Saliha Said. Natural Gas Plant. [Chemical engineering senior design project, 99-9]. , 1999. Print. Bottom of Form Bottom of Form Read More