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  1. 6 points
    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.
  2. 4 points
    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
  3. 4 points

    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.
  4. 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.
  5. 3 points



    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.
  6. 3 points
    Arun Gupta

    What is the Arrhenius equation used for?

    this explains well http://www.chemguide.co.uk/physical/basicrates/arrhenius.html
  7. 2 points
    To make available the listing of new appropriate jobs, we want to start a new section.... but before that we want to hear from you on the following points Your participation and reply to this post is important to take the decision to start the same. Which country are you staying in ? What type of job are you looking - Dream profile , dream company How much work experiemce do you have? Can you ask your current company's HR manager to post job openings on the site - This is very important Any suggestions and ideas do you have to get it started ?
  8. 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.
  9. 2 points



    Heuristics in Chemical Engineering Rule of Thumb for Engineers Although experienced engineers know where to find information and how to make accurate computations, they also keep a minimum body of information in mind on the ready, made up largely of shortcuts and heuristics. The present compilation may fit into such a minimum body of information, as a boost to the memory or extension in some instances into less often encountered areas. Topics included COMPRESSORS AND VACUUM PUMPS CONVEYORS FOR PARTICULATE SOLIDS COOLING TOWERS CRYSTALLIZATION FROM SOLUTION DISINTEGRATION • DISTILLATION AND GAS ABSORPTION A DISTILLATION AND GAS ABSORPTION B DISTILLATION AND GAS ABSORPTION C DRIVERS AND POWER REOCVERY EQUIPMENT DRYING OF SOLIDS • EVAPORATORS EXTRACTION, LIQUID-LIQUID • FILTRATION FLUIDIZATION OF PARTICLES WITH GASES HEAT EXCHANGERS INSULATION MIXING AND AGITATION PARTICLE SIZE ENLARGEMENT PIPING PUMPS REACTORS REFRIGERATION SIZE SEPARATION OF PARTICLES UTILITIES: COMMON SPECIFICATIONS VESSELS (DRUMS) VESSELS (PRESSURE) VESSEL (STORAGE TANKS)
  10. 2 points

    From the album petroleum

  11. 2 points

    From the album petroleum

  12. 2 points
    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.
  13. 2 points
    What is the Arrhenius equation used for? You can ▪ Answer this question ▪ Like the best answer ▪ Share to get more answers
  14. 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
  15. 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
  16. 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.
  17. 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...!!!
  18. 1 point

    Version 1.0.0


    Contents HEAT TRANSFER LAW APPLIED TO HEAT EXCHANGERS 2 Heat Transfer by Conduction 3 The Heat Conduction Equation 9 Heat Transfer by Convection 12 Forced Convection 12 Natural Convection 14 Heat Transfer by Radiation 15 Overall heat transfer coefficient 18 Problems 22 DESIGN STANDARDS FOR TUBULAR HEAT EXCHANGERS 23 Size numbering and naming 23 Sizing and dimension 27 Tube-side design 32 Shell-side design 33 Baffle type and spacing 33 General design consideration 35 THERMAL AND HYDRAULIC HEAT EXCHANGER DESIGN 37 Design of Single phase heat exchanger 37 Kern’s Method 45 Bell’s method 49 Pressure drop inside the shell and tube heat exchanger 57 Design of Condensers 65 Design of Reboiler and Vaporizers 72 Design of Air Coolers9 85 MECHANICAL DESIGN FOR HEAT EXCHANGERS10 88 Design Loadings 88 Tube-Sheet Design as Per TEMA Standards 90 Design of Cylindrical shell, end closures and forced head 91 References 95
  19. 1 point
    Dharmapuri Chemical engineering production trainee Fresher Any jobs please inform
  20. 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.
  21. 1 point

    From the album petroleum

  22. 1 point
    Arun Gupta


    From the album petroleum

  23. 1 point
    Arun Gupta


    From the album petroleum

  24. 1 point
    Arun Gupta


    From the album petroleum

  25. 1 point

    Version 1.0.0


    A novel orange peel adsorbent developed from an agricultural waste material was characterised and utilised for the removal of Remazol Brilliant Blue from an artificial textile-dye effluent. The adsorption thermodynamics of this dye-adsorbent pair was studied in a series of equilibrium experiments. The time to reach equilibrium was 15 h for the concentration range of 30 mg L-1 to 250 mg L-1. The adsorption capacity decreased with increasing temperature, from 9.7 mg L-1 at 20 °C to 5.0 mg L-1 at 60 °C. Both the Langmuir and Freundlich isotherm models fitted the adsorption data quite reasonably. The thermodynamic analysis of dye adsorption onto the orange peel adsorbent indicated its endothermic and spontaneous nature. Thus, the application of orange peel adsorbent for the removal of dye from a synthetic textile effluent was successfully demonstrated.
  26. 1 point
    Haris Shahid

    What is difference between fouling and scaling?

    Fouling is any particles that are able to "cling" to the surface of the plate, but can be removed relatively easily by mechanical means such as hydro blasting or scrubbing with a soft bristle brush. Fouling can usually be taken care of during a typical maintenance cycle. Scaling is a very different phenomenon from fouling. Scaling occurs when a mineral film coats the entire surface of a heat exchanger. The most common forms of scale are usually from calcium-based salts such as calcium sulfate or calcium carbonate. They belong to a family of salts referred to as "reverse soluble salts". Reverse soluble salts act in the opposite way. As temperature increases, their solubility decreases in water. So, when you heat a water-based stream containing these salts, the salts begin to plate out onto the heat transfer surfaces. Once this happens, the heat transfer performance of your heat exchanger will decrease quickly. Scale cannot be removed by hydro blasting or your typical scrubbing. The only reliable way to remove these types of scale is by acid cleaning the plates. The scale has to be dissolved and carried away from the plate surface.
  27. 1 point
    vivek g

    Cement Technology

    very useful contents
  28. 1 point
    Outstanding properties of teflon:- Uses of Teflon and Properties 1. Chemicals includes ozone,chlorine,acetic acid ammonia,sulphuric acid and hydrochloric acid. The coatings are affected by molten alkali metals and highly reactive fluorinating agents. 2. It is weather and UV resistant Teflon 3. It has excellent optical properties 4. It is non stick Very few solid substances can permanently stick to a Teflon coating, where as tacky materials may show some adhesion, almost all substances release easily from the coating. 5. It has outstanding performance at extreme temperatures. Teflon can temporarily withstand temperatures of 260C and cryogenic temperatures of -240C and will then also have the same chemical properties.It has an initial melting point of 342C (+- 10C) temperature. 6. It has low coefficient of friction. Coefficient of friction is the ratio of the force required to make two surfaces slide over each other. A low coefficient of friction equals low resistance and smooth operation. Thus there is no difficulty in sliding one surface against another. The coefficient of friction of Teflon is generally in the range of 0.05 to 0.20, depending on the load, sliding speed, and type of Teflon coating used. 7. Teflon finishes are both hydrophobic and oleophobic, which makes cleanup easier and more thorough. 8. Over many different frequencies, low dissipation factor and high surface resistivity teflon has a high dielectric strength. The high voltage that the insulating material can withstand before it breaks down is its dielectric strength . In addition to it teflon has a low dissipation factor; that is the percentage of electrical energy absorbed and lost when current is applied to an insulating material. A low dissipation factor indicates that the absorbed energy dissipated as heat is low.The high surface resistivity indicates the electrical resistance between opposite edges of an unit square on the surface of an insulating material. Uses of Teflon:- The various market applications of Teflon include : Computer pin belt 1. In electronics industry it is used on account of its insulation property in wires and system components.Also used because of its outstanding electrical performance and durability. Uses for coating 2. Used for metal finishing, paints and coatings,as flour additives can be added to reduce the wear and tear on load-bearing surfaces. For example in inks and lithographic printing, thermoplastics and molded gears, protective industrial surfaces, lubricants to thicken, sterile packaging, etc. Uses as automobile air bags 3. In optical devices, as it can be used as clear coating, requiring a low refractive index and still perform in aggressive chemical environments over a wide range of use temperatures and light waves (UV-IR). For example, it is found in lightweight surgical lamps, photovoltaic cell glazing, etc. 4. In automobiles it finds its uses as airbag systems, fuel hose permeation barrier, fuel system, chassis, brake systems, oil filter, etc. 5. Used as nonstick coating on cooking devices like pans, oven , tawa as it is nonstick and exceptional performance at high temperatures.
  29. 1 point
    What are the different types of equipments for the conveyance of solids? The various types of equipments available for the conveyance of solids are as follows: Gravity Chutes: This equipment relies on gravity for the solids to fall under. Air Slides: In this equipment the particles are suspended in air, and flow at an angle to the horizontal. Belt Conveyors: This equipments use a belt to transfer the solids. Screw Conveyors: The solids are moved using a rotating helical impeller. Bucket elevators: The solids are moved using buckets which are attached to a belt in motion. Vibrating Conveyors: The solid particles are subjected to vibrations and travel over to a table in a series of steps. Pneumatic/ Hydraulic Installations: The particles are transported over a stream of air or water.
  30. 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.
  31. 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
  32. 1 point
    What is corrosion? Which is the most important material used for metallic coating?
  33. 1 point
    Arun Gupta

    Fuel And Combustion

    Version 1.0.0


    The various types of fuels like liquid, solid and gaseous fuels are available for firing in boilers, furnaces and other combustion equipments. The selection of right type of fuel depends on various factors such as availability, storage, handling, pollution and landed cost of fuel. The knowledge of the fuel properties helps in selecting the right fuel for the right purpose and efficient use of the fuel. The following characteristics, determined by laboratory tests, are generally used for assessing the nature and quality of fuels.
  34. 1 point
    Hi mam, I found the quiz interesting and stimulating to know more in the field of stoichiometry. I doubt some of the answers aren't correct. 1) same osmotic pressure----isn't it isotonic ?? 2) colligative property --- does it depend on constitution of the solute?? 3) calorific value --- isn't it heat of combustion?? 4) total vapor presssure for ideal solution - isn't it linear. (might be a little curved for solutions of positve or negative deviation) I might be wrong too. Please check once and correct me.
  35. 1 point

    Version 2.0.0


    Liquid–liquid extraction is also known as solvent extraction and partitioning is a method to separate compounds based on their relative solubilities in two different immiscible liquids, usually water and an organic solvent. It is an extraction of a substance from one liquid into another liquid phase.
  36. 1 point

    Version 1.0.0


    Liquid–liquid extraction also known as solventextraction and partitioning, is a method to separate compounds based on their relative solubilities in two different immiscible liquids, usually water and an organic solvent. It is an extraction of a substance from one liquid into another liquid phase.
  37. 1 point

    Version 1.0.0


    Only approved containers and portable tanks shall be used for storage and handling of flammable liquids. Approved safety cans or Department of Transportation approved containers shall be used for the handling and use of flammable liquids in quantities of 5 gallons or less, except that this shall not apply to those flammable liquid materials which are highly viscid (extremely hard to pour), which may be used and handled in original shipping containers. For quantities of one gallon or less, the original container may be used, for storage, use and handling of flammable liquids.
  38. 1 point
    • Graded Mode
    • 5 minutes
    • 19 Questions
    • 20 Players
    Are you a chemical engineering ? Lets check your knowledge on basics of Chemical Engineering Take quiz and check it out and share the same with your friends.
  39. 1 point
  40. 1 point
    In this we should add compressor design
  41. 1 point
    Both equipment is based on phase change phenomenon . In heat exchanger use fast and stabilised the liquid to its general temperature but cooling tower use large section to exposed to liquid to gas phase phenomenon.
  42. 1 point
    Direct mixing and heat transfer take place in case of cooling tower while indirect mixing and heat transfer happens in heat exchangers.
  43. 1 point
    Jay Lokwani

    How can we measure entropy?

    You cannot measure entropy of any system at any point. You can only measure the change in entropy of system by determining the state of system. Only entropy known is the one given by third law of thermodynamics which says the entropy of perfectly crystalline solid at 0 K temperature is zero.
  44. 1 point
    In case of centrifugal pump the liquid would keep on revolving in side the pump and would heat up though Electric consumption would be low than if the discharge valve is open.
  45. 1 point
    What is the difference between distillation and fractionation? You can ▪ Answer this question ▪ Like the best answer ▪ Share to get more answers
  46. 1 point
    Calculating heat exchanger effectiveness allows engineers to predict how a given heat exchanger will perform a new job. Essentially, it helps engineers predict the stream outlet temperatures without a trial-and-error solution that would otherwise be necessary. Heat exchanger effectiveness is defined as the ratio of the actual amount of heat transferred to the maximum possible amount of heat that could be transferred with an infinite area. Two common methods are used to calculate the effectiveness, equations and graphical. The equations are shown below. Eqn(1) Eqn(2) where: U = Overall heat transfer coefficient A = Heat transfer area Cmin = Lower of the two fluid's heat capacities Cmax = Higher of the two fluid's heat capacities Often times, another variable is defined called the NTU (number of transfer units): NTU = UA/Cmin When NTU is placed into the effectiveness equations and they are plotted, you can construct the plots shown below which are more often used than the equations: Fig1: Heat Exchanger Effectiveness for Countercurrent Flow Fig2: Heat Exchanger Effectiveness For Cocurrent Flow Then, by calculating the Cmin/Cmax and the NTU, the effectiveness can be read from these charts. Once the effectiveness has been found, the heat load is calculated by: Q = Effectiveness x Cmin x (Hot Temperature in - Cold Temperature in) For calculating the outlet temperatures we use the equations stated below Eqn(3) Eqn(4)
  47. 1 point
    For our example which deals with the azeotropic mixture formed between benzene and cyclohexane, we have chosen extractive distillation (one of the homogeneous azeotropic distillation methods). The reason of choosing this method is due to the availability of information regarding this separation technique and its tendency to operate more efficiently, i.e. in separating and recycling the separating agent. A brief discussion of the process is given below. After the mixture exited as the bottom product of the flash unit, it contains mostly our desire product of cyclohexane and also a significant amount of unreacted benzene, which is to be recycled back to the reactor for further conversion. Our main goal now is to further separate the remaining components in the mixture. As cyclohexane and benzene have been encounter most of the remaining composition with the mole % of 44.86 and 54.848 respectively (Table 1), we will consider this to be a binary mixture in our further discussion. From the process flowsheeting, we would like to operate the distillation column at the pressure of 150 kPa. At this condition, cyclohexane and benzene will have boiling points of 94.34 °C and 93.49 °C respectively (Figure 3). This is a typical case where conventional distillation would struggle to perform the separation of this type of close boiling mixture. Thus, a special type of distillation technique, i.e. extractive distillation has been chosen in order to purify the desire product, i.e. cyclohexane to our desired purity of 99.3%. As can be shown from Figure 3, this binary composition will form a minimum boiling, homogeneous azeotrope at the temperature of 91oC and the corresponding composition at this point will be 45.5 mole % for cyclohexane and 55.5 mole % for benzene (Figure 4). Temperature 5.4279 °C Pressure 1376.6 kPa Molar Flow Rate (kg mol/h)  Hydrogen 0.914 Cyclohexane 159.447 Benzene 194.944 n-Hexane 0.127 Total 355.430 Mole % Composition  Hydrogen 0.256 Cyclohexane 44.861 Benzene 54.846 n-Hexane 0.036 Total 1.000 Figure 3: T-xy Plot for Benzene and Cyclohexane at 150 kPa Figure 4: x-y Plot for Benzeneand Cyclohexane Solvent Selection for the Benzene-Cyclohexane Binary Mixture In order to perform a successive extractive distillation, a solvent needs to be chosen to "break" the azeotrope that forms at the operating pressure of the distillation column. Recommended solvent for the benzene-cyclohaxane mixture from the literature,,,is aniline, with a solvent to feed ratio (S/F) of 4, which will shift the azeotropic point toward the corner of the high-boiling component cyclohexane, and the equilibrium curve of the original components fall below the diagonal (Figure 5). Figure 5: Elimination of Azeotropic Point with the Addition of a Separating Agent As was stated in the above section, the primary goal of solvent selection is to identify a group of feasible solvents to perform a good separation. The desired product, i.e. cyclohexane should have a purity of above 99% to meet the market standard. Aniline was the first solvent that had been put to the simulator to be tried out, as it is of the same homologous group as benzene. As can be shown from the result in Table 2, this solvent will produce the desire production rate of 150 with the solvent flow rate of 3500, i.e. a S/F ratio of 9.85. However, the product purity can only reach 70.08% and this does not meet our product specification. As a result, other solvent may have to be researched to perform the desire separation. We will have to perform the solvent selection criteria as stated in the preceding section. At the column pressure of 150 kPa, cyclohexane and benzene boil at 94.34 °C and 93.49 °C respectively and form a minimum-boiling azeotrope at 91 °C. The natural volatility of the system is benzene > cyclohexane, so the favored solvents most likely will be those that cause the benzene to be recovered in the distillate. However, in order to get a better quality of product, we would like to recover cyclohexane as the distillate rather than from the bottom stream. Thus, solvent to be chosen should give positive deviations from Raoult's law for cyclohexane and negative (or zero) deviation for benzene. Feed Stream Molar Flow Rate (kg mol/h)  Hydrogen 0.914 Cyclohexane 159.447 Benzene 194.944 n-Hexane 0.127 Total 355.43 Solvent Stream (Aniline) molar flow rate (kg mol/h) 3500 Solvent/Feed (S/F) ratio 9.85 Distillate Product Molar Flow Rate (kg mol/hr)  Hydrogen 0.914 Cyclohexane 150 Benzene 62.956 n-Hexane 0.127 Aninline 0.058 Total 214.05 Mole % Composition in the Distillate Product  Hydrogen 0.427 Cyclohexane 70.08 Benzene 29.41 n-Hexane 0.059 Aniline 0.027  Total 1.000   Solvent Class Solute Class Group 1 2 3 4 5 6 7 8 9 10 11 12 11 Aromatic, olefin, halogen aromatic, + + + 0 + 0 0 - 0 + 0 0 multihola paraffine without active H, monohalo paraffine 12 Paraffin, carbon disulfide + + + + + 0 + + + + 0 + Solvent/solut eclass Group Solvent/soluteclass Group 4 Active -H in multihalo paraffin 8 Primanry amine, ammonia, amide with 2H or N Ether, oxide, sulfoxide 7 Secamine 9 Turning to the Robbins Chart(Table 3), we note that solvents that may cause the positive deviation for cyclohexane (Class 12) and negative (or zero) to benzene (Class 11) came from the groups of 4, 7, 8 and 9, which consist of polyol, amine and ether. We further consider the solubility, the hydrogen bonding effect, and also the homologous characteristic of the solvent with the corresponding components in the feed mixture. As few candidate solvents that had been put to the computer simulation, included phenol (homologous to benzene), 1,2-benzenediol (homologous to benzene, with -OH group that will produce hydrogen bonding), 1,3-butanediol (with -OH group that will produce hydrogen bonding), and also 1,2-propanediol (same characteristic as with 1,3-butanediol). 1,2-propanediol (often known as propylene glycol), seem to give the most promising results compared to the other solvents. This result may be caused from the high solubility of benzene in this solvent and the hydrogen bonding that were formed between the two constituents. Simulation result of this solvent can be view in Table 4.
  48. 1 point



    What is Chemical Engineering & difference from chemical process
  49. 1 point

    Version 2


    Separation Trains Azeotropes
  50. 1 point

    Version 1.0.0


    Petroleum Refining Engineering-II Course outline 1. Simplified overall crude oil refinery picture 2. Major refinery products and tests: Brief description 3. Separation process: Atmospheric and vacuum distillations, lube oil extraction, dewaxing, deasphalting, and clay treatment. 4. Catalysts used in refinery operations 5. Conversion processes: Brief description of alkylation, polymerization, isomerization of light paraffins, hydrotreating, catalytic reforming, catalytic cracking, hydrocracking, visbreaking of resids, and coking. 5. Material and energy balances for refinery processes: Simulation of refinery processes 6. Design guidelines for the selected refinery equipment

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