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Chemical Engineering


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  1. 3 points



    A shell and tube heat exchanger is a class of heat exchanger designs. It is the most common type of heat exchanger in oil refineries and other large chemical processes, and is suited for higher-pressure applications. As its name implies, this type of heat exchanger consists of a shell (a large pressure vessel) with a bundle of tubes inside it. One fluid runs through the tubes, and another fluid flows over the tubes (through the shell) to transfer heat between the two fluids. The set of tubes is called a tube bundle, and may be composed of several types of tubes: plain, longitudinally finned, etc.
  2. 2 points



    A waste heat recovery unit (WHRU) is an energy recovery heat exchanger that recovers heat from hot streams with potential high energy content, such as hot flue gases from a diesel generator or steam from cooling towers or even waste water from different cooling processes such as in steel cooling.
  3. 2 points
    Arun Gupta

    What is the Arrhenius equation used for?

    this explains well http://www.chemguide.co.uk/physical/basicrates/arrhenius.html
  4. 2 points



    Includes two separate downloads in Adobe Acrobat format: Quiz for Heat Exchanger Selection and Design and Good Practices for Heat Exchanger Selection and Design
  5. 1 point
    Arun Gupta

    Why baffles are used in reactors?

    The ideal CSTR model assumes that the fluid in the reactor is perfectly mixed, and that there are no concentration gradients inside the reactor. However, in a real-world stirred tank reactor, you won't have perfect mixing and there will be concentration gradients present. The baffles contribute additional disturbance to the flow created by the mixer, and provide more effective mixing. So, including the baffles brings you closer to the ideal of perfect mixing
  6. 1 point

    Version 1.0.0


    Chemical kinetics is the study and discussion of chemical reactions with respect to reaction rates, effect of various variables, re-arrangement of atoms, formation of intermediates etc. There are many topics to be discussed, and each of these topics is a tool for the study of chemical reactions.
  7. 1 point
    Can an Atom have existence of life in it. Yes can be...!!! Science, is a subject that makes a rule on whatever we observer and can be proved repeatedly via experiment. So, according to Science; what ever we dream is not possible since that can not be proven. What if I tell you Scientific TOOLS that are used for Experiment are a BOTTLENECK. Since, they can not connect with our visualization. There comes the ANALOGY in picture to overcome the bottleneck and connect you with your past, present and future or what ever you visualize/dream. Analogy is one thing that can take our visualization to any extent. Basically, people use Analogies daily in their life; but can't feel that they have used it. Since they don't realize it. I will try to take you to a tour where you would learn what is an analogy and how to use it. I have an analogy and that came when I use to dream about Atoms in bed during my schooling. I use to think that an atom is an analogy to our solar system; where its Nucleus is an analogy to Sun and revolving Electrons is an analogy to Planets revolving around Sun. So, why do you think this analogy should work to prove that atoms may have existence of life in it...? In books Electrons are mentioned as dumble shaped cloud rotating around Nucleus. They(Electron) have negative charge which keeps them attracted to a positively charged protons present in Nucleus...!!! Aaha, what a theory. . May be...!!! Basically, Electron is a mass and should have same properties as masses, for e.g. we use to launch our satellite and keep them stable around Earth. The theory of mass says that two masses attract each other and the attraction is directly proportional to respective masses and inversely to distance between them. Don't you think instead of charge theory which says presence of charge on Electron and Protons(in Nucleus); they are attracted/attached to each other by theory of mass and hence electron are stable and keep rotating and revolving around its Nucleus. Every thing in books is an opinion / personal observations or theory about things which are deep to understand. I too am putting my analogy here between an Atom and Solar system for you all to understand existence of life in an Atom. Now here's my Analogy...!!! As per my analogy, Electrons are similar to any planets which revolves around Sun(Nucleus) and also may have existence of life similar to Earth. The Scientist used to call Electron as a Cloud. The speed at which earth is rotating around Sun can be seen, proven and calculated b Science. But on other hand if we consider Electrons; they too are rotating and revolving, the only difference is the speed at which this is happening. If we were able to capture the picture at this speed (which is a bottleneck for Science) then it would have been easier to believe that it is not a cloud but a system which is similar to something we have in nature and we won't call it as a cloud; instead we would call this as something similar to solar system and is very very tiny. The cloud theory of electron tells that, there are another masses rotating around Electron like we have moon around Earth at high speed making our eyes believe that its a cloud. Thank you...!!!
  8. 1 point

    Version 1.0.0


    Chemical reaction engineering (reaction engineering or reactor engineering) is a specialty in chemical engineering or industrial chemistry dealing with chemical reactor. Frequently the term relates specifically to catalytic reaction systems where either a homogeneous or heterogeneous catalyst is present in the reactor. Sometimes a reactor per se is not present by itself, but rather is integrated into a process, for example in reactive separations vessels, retorts, certain fuel cells, and photocatalytic surfaces. The issue of solvent effects on reaction kinetics is also considered as an integral part.
  9. 1 point



    A cooling tower is a heat rejection device that rejects waste heat to the atmosphere through the cooling of a water stream to a lower temperature. Cooling towers may either use the evaporation of water to remove process heat and cool the working fluid to near the wet-bulb air temperature or, in the case of closed circuit dry cooling towers, rely solely on air to cool the working fluid to near the dry-bulb air temperature. Common applications include cooling the circulating water used in oil refineries, petrochemical and other chemical plants, thermal power stations and HVAC systems for cooling buildings. The classification is based on the type of air induction into the tower: the main types of cooling towers are natural draft and induced draft cooling towers. Cooling towers vary in size from small roof-top units to very large hyperboloid structures (as in the adjacent image) that can be up to 200 meters (660 ft) tall and 100 meters (330 ft) in diameter, or rectangular structures that can be over 40 meters (130 ft) tall and 80 meters (260 ft) long. The hyperboloid cooling towers are often associated with nuclear power plants,[1] although they are also used in some coal-fired plants and to some extent in some large chemical and other industrial plants. Although these large towers are very prominent, the vast majority of cooling towers are much smaller, including many units installed on or near buildings to discharge heat from air conditioning.
  10. 1 point



    Oil refinary processes are the chemical engineering processes and other facilities used in petroleum refineries (also referred to as oil refineries) to transform crude oil into useful products such as liquefied petroleum gas (LPG), gasoline or petrol, kerosene, jet fuel, diesel oil and fuel oils. Petroleum refineries are very large industrial complexes that involve many different processing units and auxiliary facilities such as utility units and storage tanks. Each refinery has its own unique arrangement and combination of refining processes largely determined by the refinery location, desired products and economic considerations. Some modern petroleum refineries process as much as 800,000 to 900,000 barrels (127,000 to 143,000 cubic meters) per day of crude oil.
  11. 1 point

    From the album petroleum

  12. 1 point
    Arun Gupta


    From the album petroleum

  13. 1 point

    From the album petroleum

  14. 1 point
    Arun Gupta


    From the album petroleum

  15. 1 point
    Arun Gupta


    From the album petroleum

  16. 1 point
    Arun Gupta


    From the album petroleum

  17. 1 point
    Arun Gupta


    Version 1.0.0


    Distillation is a widely used method for separating mixtures based on differences in the conditions required to change the phase of components of the mixture. To separate a mixture of liquids, the liquid can be heated to force components, which have different boiling points, into the gas phase. The gas is then condensed back into liquid form and collected. Repeating the process on the collected liquid to improve the purity of the product is called double distillation. Although the term is most commonly applied to liquids, the reverse process can be used to separate gases by liquefying components using changes in temperature and/or pressure. A plant that performs distillation is called a distillery. The apparatus used to perform distillation is called a still. Distillation.mp4
  18. 1 point

    What is carbon sequestration?

    What is carbon sequestration? A technique for capturing carbon dioxide for a long term in order to reduce its effects on global warming.
  19. 1 point
    What are the merits of using a falling film evaporator? The advantages of using falling film evaporators are as follows: These types of evaporators have very high heat transfer coefficients ranging from 2000-5000 W/m(square) for water and 500 to 1000 for organic liquids The residence times are short in case of heated surfaces, 5-10 seconds without recirculation They have very low pressure drops, 0.2-0.5 kN/m(square) , These evaporators are well suited for vacuum operations as well. The evaporation ratios are very high. 70 per cent without and 95 per cent with recirculation, They have a very wide operating range, they can provide as much as 400% of the minimum throughput, In addition to the above advantages they have a low cost of operation and are less susceptible to fouling
  20. 1 point
    To prevent galvanic corrosion in iron and steel alloys, coatings made from zinc and aluminum are helpful. Large components, such as bridges and energy windmills, are often treated with zinc and aluminum corrosion resistant coatings because they provide reliable long-term corrosion prevention. Steel and iron fasteners, threaded fasteners, and bolts are often coated with a thin layer of cadmium, which helps block hydrogen absorption which can lead to stress cracking.
  21. 1 point
    What is corrosion? Which is the most important material used for metallic coating?
  22. 1 point

    Version 1.0.0


    The course content will be suitable for a wide range of personnel within a cement manufacturing company including junior/middle management, technicians, production and control room staff, etc and also for others who wish to gain a comprehensive understanding of the complete cement manufacturing process.
  23. 1 point
    Arun Gupta


    Version 1.0.0


    A boiler is an enclosed vessel that provides a means for combustion and transfers heat to water until it becomes hot water or steam. The hot water or steam under pressure is then usable for transferring the heat to a process. Water is a useful and cheap medium for transferring heat to a process. When water is boiled into steam its volume increases about 1,600 times, producing a force that is almost as explosive as gunpowder. This causes the boiler to be extremely dangerous equipment and should be treated carefully.Liquid when heated up to the gaseous state this process is called evaporation. The heating surface is any part of the boiler; hot gasses of combustion are on one side and water on the other. Any part of the boiler metal that actually contributes to making steam is heating surface. The amount of heating surface of a boiler is expressed in square meters. The larger the heating surface a boiler has, the more efficient it becomes.
  24. 1 point
    Pressurize in shell side and check in individual tubes for leakage

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