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I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
I am chemical engineer magazine 6 2013
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I am chemical engineer magazine 6 2013

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I am chemical engineer magazine

I am chemical engineer magazine

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  • 1. 6/2013 M A G A Z I N E We reached 10,000+ Likes in https://www.facebook.com/IamCheEng
  • 2. For your support
  • 3. I am a Chemical Engineer • We discuss Chemical Engineering and provide some information and news. • We would like to think of our page as an exchange page of experience and information. https://www.facebook.com/IamCheEng Slogan Connecting chemical engineers. Vision Improving the chemical Engineering skills to meet the work environment & to decrease the gap between study and work. Mission Gathering information about any chemical engineering fields.
  • 4. What Is Chemical Engineering? Chemical engineering basically is applied chemistry. It is the branch of engineering concerned with the design, construction, and operation of machines and plants that perform chemical reactions to solve practical problems or make useful products. What Is a Chemical Engineer? Like all engineers, chemical engineers use math, physics, and economics to solve technical problems. The difference between chemical engineers and other types of engineers is that they apply a knowledge of chemistry in addition to other engineering disciplines. Chemical engineers sometimes are called 'universal engineers' because their scientific and technical mastery is so broad. What Do Chemical Engineers Do? Some chemical engineers make designs and invent new processes. Some construct instruments and facilities. Some plan and operate facilities. Chemical engineers have helped develop atomic science, polymers, paper, dyes, drugs, plastics, fertilizers, foods, petrochemicals... pretty much everything. They devise ways to make products from raw materials and ways to convert one material into another useful form. Chemical engineers can make processes more cost effective or more environmentally friendly or more efficient. As you can see, a chemical engineer can find a niche in any scientific or engineering field.
  • 5. Learn something about everything
  • 6. What is the Function of a Gate Valve? Definition A gate valve, also referred to as a sluice valve, is a valve that opens and closes to regulate fluid flow. A gate valve opens by lifting a rectangular or round gate or wedge, often called a sliding door, out of the fluid's path to allow it to flow though. Function Gate valves are used in straight-flow fluid systems where a minimum amount of friction is required. Unlike other valves, gate valves are constructed to be used either completely open or closed. If partially open, the fluid velocity can damage the gate valve's seal and cause leakage. Stems Gate valves contain either a non-rising or rising stem. Rising stems are used as a visual indication of the valve position and lift when a valve is open. Non-rising stems are used for underground gate valves or when vertical space is constricted.
  • 7. Different types of Flowmeters with their Diagrams : i. ii. iii. iv . v. vi. vii. viii. ix. Orifice Flowmeter Venturi Flowmeter Nozzle Flowmeter Pitot Tube Flowmeter Wedge Flowmeter Vortex Flowmeter Ultrasonic Flowmeter Turbine Flowmeter Magnetic Flowmeter
  • 8. Manometer A Manometer is a device which can be used to measure pressure of fluids(i.e liquids and Gases). PRINCIPLE: Manometers are those pressure measuring devices which are based on the principle of balancing the column of liquid (whose pressure is to be found) by the same or another column of liquid. They are of two types 1. simple manometers 2. Differential manometers simple manometers are those which measure pressure at a point in a fluid containing in the pipe or a vessel. On the other hand Differential manometers measure the difference of pressure between any two points in a fluid contained in a pipe or vessel.
  • 9. Feedforward Control : In contrast to feedback control, feedforward control acts the moment a disturbance occurs, without having to wait for a deviation in process variable. This enables a feedforward controller to quickly and directly cancel out the effect of a disturbance. To do this, a feedforward controller produces its control action based on a measurement of the disturbance. When used, feedforward control is almost always implemented as an add-on to feedback control. The feedforward controller takes care of the major disturbance, and the feedback controller takes care of everything else that might cause the process variable to deviate from its set point.
  • 10. In our example of the heat exchanger, in which the major disturbances come from changes in process flow rate, the latter can be measured and used for adjusting the steam flow rate proportionally. This is done by the feedforward controller. Implementing Feedforward Control : Many PID controllers have an external connection for adding an input from a feedforward controller. Otherwise the output of the feedforward controller can be externally added to the output of the feedback controller. Review your controller documentation and take special care with scaling the feedforward signal. Many PID controllers expect the feedforward signal to be scaled between -100% and +100%.
  • 11. Feedforward and feedback control is often combined with cascade control, to ensure that their control actions manipulate the physical process linearly, eliminating control valve nonlinearities and mechanical problems. If several major disturbances exist, a feedforward controller can be implemented for each of them. The outputs of all the feedforward controllers can be added together to produce one final feedforward signal. Only consider disturbances that meet these criteria: Measurable – if it can’t be measured you can’t control from it Predictable effect on the process variable – most disturbances will fall in this class Occur so rapidly that the feedback control cannot deal with them as they happen.
  • 12. Cascade Control : Cascade Control Systems contain integrated sets of control loops * Primary Loop: Monitors the control variable and uses deviation from its setpoint to provide an output to the secondary loop. * Secondary Loop: Receives its setpoint from the primary loop and controls the reference variable accordingly. Benefits of Cascade Control 1- Effectively accounts for external disturbances 2- Reduces dead time in variable response 3- Compatible with other Control Systems, such as FeedBack and Feed-Forward Control Architectures
  • 13. Disadvantages of Cascade Control 1- Multiple control loops make physical and computational architecture more complex 2- Additional controllers and sensors can be costly
  • 14. What is the Difference between rising stem gate valve and non rising stem gate valve? Rising stem gate Valve - Stem threads are out side of valve body and in no contact with fluid medium. Stem rises while opening the valve (by hand wheel). Since the stem threads are located outside obviously it needs some more vertical clearance space while opening the valve. Non Rising Stem gate Valve - Stem threads are inside the the valve body and it is in contact with fluid medium. Hence, lot of chances for fouling the threads and these types of valves only can be used in clean liquids and gases. Less vertical clearance space required while opening the valve.
  • 15. Foot valve: a check valve on the foot of a suction line to prevent back-flow. A suction valve or check valve at the lower end of a pipe; esp., such a valve in a steam-engine condenser opening to the air pump. -A foot valve is nothing more than a swing check valve operating in the vertical position at the the liquid entry to the vertical suction line of a sump pump or another type of pump that has a negative suction lift due to gravity - i.e., the pump is usually located above the liquid level of the suction vessel or container. If there is any logic in this description it is that the check valve is located at the "foot" of the vertical pipe run. But it has to be understood that we are talking about a check valve - not another type of valve. The function of a foot valve is to contain the liquid inventory within the pump casing and the suction line in the event the pump is shut down or stopped. This action preserves the liquid priming of the pump and allows for a successful, instant liquid pumping start up during the next, subsequent pump startup. This is especially useful when the pump is started from an isolated location and there is no one around to manually prime the pump with liquid prior to start up.
  • 16. Float type steam trap : The Float type steam trap consists of a chamber having inlet and outlet ports. The chamber contains a stainless steel ball-float connected by a lever to the inside of the chamber wall. In the body of the trap, the outlet port has valve seats fitted to accommodate a valve plug which is fitted to the lever between the float and the chamber wall. When the trap is empty, the ball float is down and the outlet valve is closed. As condensate (water) enters the trap and forms a level, the ball begins to float and rise with the rising level. At a pre-set level the rising lever actuates the valve plug and opens the valve. Condensate passes out of the trap, the level falls and the valve closes down. In this way, the level of condensate is controlled and no steam loss is incurred. This type of trap works well with heavy or light condensate loads.
  • 17. THE THERMOSTATIC STEAM TRAP This type of steam trap has a sealed, internal bellows element filled with a liquid which has a boiling point about 25°C below that of water. Heating or cooling of the element causes it to expand or contract. The bottom of the element is connected to a valve which fits into a seat in the trap body. When the trap contains steam, the bellows is expanded by boiling the liquid inside and the valve is closed. As condensate fills the trap, it cools and the bellows begins to contract as its internal liquid stops boiling. This opens the valve and the liquid is drained off and then replaced by steam. Once again the bellows expands and closes the valve.
  • 18. Relief Valves : * Pressure relief valve - A spring-loaded pressure relief valve which is designed to open to relieve excess pressure and to reclose and prevent the further flow of fluid after normal conditions have been restored. It is characterised by a rapidopening 'pop' action or by opening in a manner generally proportional to the increase in pressure over the opening pressure. It may be used for either compressible or incompressible fluids, depending on design, adjustment, or application. This is a general term, which includes safety valves, relief valves and safety relief valves. Safety valve - A pressure relief valve actuated by inlet static pressure and characterized by rapid opening or pop action. Safety valves are primarily used with compressible gases and in particular for steam and air services. However, they can also be used for process type applications where they may be needed to protect the plant or to prevent spoilage of the product being processed.
  • 19. Relief Valves : * Relief valve - A pressure relief device actuated by inlet static pressure having a gradual lift generally proportional to the increase in pressure over opening pressure. Relief valves are commonly used in liquid systems, especially for lower capacities and thermal expansion duty. They can also be used on pumped systems as pressure overspill devices. * Safety relief valve - A pressure relief valve characterised by rapid opening or pop action, or by opening in proportion to the increase in pressure over the opening pressure, depending on the application, and which may be used either for liquid or compressible fluid. In general, the safety relief valve will perform as a safety valve when used in a compressible gas system, but it will open in proportion to the overpressure when used in liquid systems, as would a relief valve.
  • 20. Fluidized-Bed Heat Exchangers: In a fluidized-bed heat exchanger, one side of a two-fluid exchanger is immersed in a bed of finely divided solid material, such as a tube bundle immersed in a bed of sand or coal particles. At a ‘‘proper’’ value of the fluid velocity, the upward drag force is slightly higher than the weight of the bed particles. As a result, the solid particles will float with an increase in bed volume, and the bed behaves as a liquid. This results in a uniform temperature for the total bed with an apparent thermal conductivity of the solid particles as infinity. Chemical reaction is common on the fluidized side in many process applications, and combustion takes place in coal combustion fluidized beds. The common applications of the fluidized-bed heat exchanger are drying, mixing, adsorption, reactor engineering, coal combustion, and waste heat recovery.
  • 21. There are four processes in the Rankine cycle. These states are identified by numbers (in brown) in the above Ts diagram. Process 1-2: The working fluid is pumped from low to high pressure. As the fluid is a liquid at this stage the pump requires little input energy. Process 2-3: The high pressure liquid enters a boiler where it is heated at constant pressure by an external heat source to become a dry saturated vapor. The input energy required can be easily calculated using mollier diagram or h-s chart or enthalpyentropy chart also known as steam tables.
  • 22. Process 3-4: The dry saturated vapor expands through a turbine, generating power. This decreases the temperature and pressure of the vapor, and some condensation may occur. The output in this process can be easily calculated using the Enthalpy-entropy chart or the steam tables. Process 4-1: The wet vapor then enters a condenser where it is condensed at a constant temperature to become a saturated liquid. by the condensers.
  • 23. In an ideal Rankine cycle the pump and turbine would be isentropic, i.e., the pump and turbine would generate no entropy and hence maximize the net work output. Processes 1-2 and 3-4 would be represented by vertical lines on the T-S diagram and more closely resemble that of the Carnot cycle. The Rankine cycle shown here prevents the vapor ending up in the superheat region after the expansion in the turbine,which reduces the energy removed by the condensers.
  • 24. THERMO-DYNAMIC STEAM TRAP: This type of steam trap, when installed, has a strainer fitted into the line upstream of it, to remove solid particles of scale . .etc. As condensate enters the trap, through the inlet pipe with the steam pressure behind it, a metal disc is forced upwards into a small chamber and the condensate passes under the disc into the outlet pipe. The velocity of the water passing through the trap is low, even when the pressure is high. This is due to the density of the water being high compared to that of steam and the fact that, within the trap, the fluids pass through an angle of 180°. When all of the water has been displaced, steam begins to flow. The greater velocity of the steam below the disc and the sudden change of direction, causes a pressure drop under the disc which pulls it down onto its seat and stops the steam flow. The steam pressure in the chamber above the disc will be the same as the line pressure thereby holding the disc on its seat. When the steam above the disc cools and condenses, the chamber pressure falls and the disc is forced upwards again by the line pressure. If only steam passes into the trap, the above process is repeated with a small release of steam until the disc drops again.
  • 25. Every magazine we will introduce a special course, Today our course is PUMP AN INTRODUCTION TO PUMPING EQUIPMENT
  • 26. AN INTRODUCTION TO PUMPING EQUIPMENT WHAT IS THE PUMP? Pumps are machines which supply energy to a liquid in order to move it from place to another. The method that is used to supply this energy to the liquid determines the category into which the pump is placed and the system between the pump and the liquid final destination defines the application. Water Flood Refinery Transportation Pumps enable a liquid to: 1. Flow from a region or low pressure to one of high pressure. 2. Flow from a low level to a higher level. 3. Flow at a faster rate.
  • 27. AN INTRODUCTION TO PUMPING EQUIPMENT Pumps vary considerably in their size, construction and principle of operation. There are two main categories of pump: • • Rotodynamic pumps. Positive displacement pumps. PUMP Rotodynamic Positive displacement Centrifugal Rotary Reciprocating Axial flow Mixed flow Gear Piston Turbine Lobe Sliding Vane Screw Diaphragm Plunger
  • 28. AN INTRODUCTION TO PUMPING EQUIPMENT Centrifugal Pumps: Also known as rotary pumps, centrifugal pumps have a rotating impeller, also known as a blade, that is immersed in the liquid. Liquid enters the pump near the axis of the impeller, and the rotating impeller sweeps the liquid out toward the ends of the impeller blades at high pressure. For low flows and high pressures, the action of the impeller is largely radial. For higher flows and lower discharge pressures, the direction of the flow within the pump is more nearly parallel to the axis of the shaft, and the pump is said to have an axial flow. The impeller in this case acts as a propeller. The transition from one set of flow conditions to the other is gradual, and for intermediate conditions, the device is called a mixed-flow pump.
  • 29. AN INTRODUCTION TO PUMPING EQUIPMENT Positive-displacement Pumps: A variety of positive-displacement pumps are also available, generally consisting of a rotating member with a number of lobes that move in a close-fitting casing. The liquid is trapped in the spaces between the lobes and then discharged into a region of higher pressure. A common device of this type is the gear pump, which consists of a pair of meshing gears. The lobes in this case are the gear teeth. What is the main difference between kinetic and positive displacement pumps ? The main difference between kinetic and positive displacement pumps lies in the method of fluid transfer. A kinetic pump imparts velocity energy to the fluid, which is converted to pressure energy upon exiting the pump casing
  • 30. AN INTRODUCTION TO PUMPING EQUIPMENT A positive displacement pump moves a fixed volume of fluid within the pump casing by applying a force to moveable boundaries containing the fluid volume. Positive displacement pumps are also divided into two major pump categories : reciprocating & rotary. Reciprocating pumps transfer a volume of fluid by a crankshaft,eccentric cam or an alternating fluid pressure acting on a piston, plunger or a diaphragm in a reciprocating motion. The Table below outlines some of the main differences between centrifugal pumps, reciprocating pumps and rotary pumps. Note that “centrifugal”, “reciprocating” and “rotary” pumps are all relatively broad categories. The table below provides a comparison of features between these pump categories that generally holds true. Also, note that Table lists typical maximum flow rates and heads. It is possible to build special pumps outside the upper bounds of the pressures and flow rates listed, but such pumps would be prohibitively expensive for most applications.
  • 31. AN INTRODUCTION TO PUMPING EQUIPMENT Centrifugal Pumps Reciprocating Pumps Medium/High Capacity, Low/Medium Pressure Low Capacity, High Pressure Low/Medium Capacity, Low/Medium Pressure Maximum Flow Rate 100,000+ GPM 10,000+ GPM 10,000+ GPM Low Flow Rate Capability No Yes Yes 6,000+ PSI 100,000+ PSI 4,000+ PSI Requires Relief Valve No Yes Yes Smooth or Pulsating Flow Smooth Pulsating Smooth Variable or Constant Flow Variable Constant Constant No Yes Yes Requires Less Space Requires More Space Requires Less Space Lower Initial Lower Maintenance Higher Power Higher Initial Higher Maintenance Lower Power Lower Initial Lower Maintenance Lower Power Suitable for a wide range including clean, clear, non-abrasive fluids to fluids with abrasive, high-solid content. Suitable for clean, clear, non-abrasive fluids. Speciallyfitted pumps suitable for abrasive-slurry service. Requires clean, clear, non-abrasive fluid due to close tolerances Not suitable for high viscosity fluids Suitable for high viscosity fluids Lower tolerance for entrained gases Higher tolerance for entrained gases Parameter Optimum Flow and Pressure Applications Maximum Pressure Self-priming Space Considerations Costs Fluid Handling Rotary Pumps Optimum performance with high viscosity fluids Higher tolerance for entrained gases
  • 32. AN INTRODUCTION TO PUMPING EQUIPMENT Centrifugal Pumps Capacity: The wide variety of centrifugal pumps manufactured offer a relatively large range of available capacities. Radial-flow and mixed flow pumps are used for low to medium capacity applications. For high capacity applications, axial-flow pumps are capable of delivering flow rates in excess of 100,000 gpm. Centrifugal pumps are not stable at low flow rates, although there are special low-flow centrifugal pumps available that can deliver flow rates less than 10 gpm. However, for extreme lowflow applications (< 1 gpm), positive displacement pumps are a better selection. Reciprocating & Rotary Pumps Capacity: Reciprocating and rotary pumps are capable of capacities ranging from low to medium, with flow rates peaking at 10,000+ gpm. In theory, reciprocating pumps can be manufactured to deliver more capacity, but they become prohibitively large and expensive at high flow rates. Both reciprocating and rotary pumps are capable of delivering product at extremely low flow rates (fractions of a gpm), making them particularly suitable for many chemical injection applications.
  • 33. AN INTRODUCTION TO PUMPING EQUIPMENT Why it is necessary to install a relief valve on the discharge of the Reciprocating or Rotary pumps ? Because both reciprocating and rotary pumps will continually increase pressure when pumping against a closed discharge to the extent allowed by the driver’s horsepower. This can result in overpressure of the pump or piping components, so it is necessary to install a relief valve on the discharge of the pump capable of discharging the full capacity of the pump. Why it is not necessary to install a relief valve on the discharge of the Centrifugal pumps ? A centrifugal pump’s pressure rise is limited to the shut-off pressure on the pump curve, which is always less than the design pressure of the pump (and the piping system if properly designed). A relief valve is only needed if no other measures are provided to detect low flow conditions and shut down the pump to prevent damage. The relief valve need only be sized to pass the minimum flow rate required to maintain stable flow and prevent excessive temperature rise.
  • 34. AN INTRODUCTION TO PUMPING EQUIPMENT Centrifugal pumps and most rotary pumps provide smooth, non-pulsating flow, while reciprocating pumps produce a pulsating flow. A pulsating flow may require special design considerations in the piping system. If the pump is not located near the suction source, then acceleration head can contribute to low NPSHA problems, which may require the installation of a suction stabilizer. A pulsation dampener may need to be installed in the discharge piping to reduce pressure surges resulting from the pulsating flow. Centrifugal Pumps Variable or Constant Flow: Centrifugal pumps operate on a variable-flow, variable-head curve. As the discharge pressure decreases, the pump delivers a higher flow rate. Centrifugal pumps are favored where process conditions often require varying flow rates. For example, a level control valve must throttle the flow rate from a vessel to maintain a constant level in the vessel. A centrifugal pump is well suited to handle this process condition.
  • 35. AN INTRODUCTION TO PUMPING EQUIPMENT Reciprocating & Rotary Pumps Variable or Constant Flow: At any given speed, reciprocating and rotary pumps operate at a constant flow rate regardless of the discharge pressure. There are specific applications that require either constant flow or variable flow. Metering pumps rely on a constant flow at varying pressures, which makes reciprocating pumps and rotary pumps suitable for this application. Piston pumps used for metering will often use an adjustable stroke length to allow the operator to vary the flow rate to meet the system requirements. whereas a positive displacement pump would either require a continuous recycle to suction or a variable speed driver to accommodate the variable flow. Self-priming : Reciprocating and rotary pumps are self-priming. This is an important consideration where a prime cannot be maintained on the pump. Centrifugal pumps are not inherently selfpriming, although some manufacturers do specially design selfpriming units. External priming sources, such as an eductor or vacuum pump can also be employed.
  • 36. AN INTRODUCTION TO PUMPING EQUIPMENT Costs Considerations : The reciprocating pump will generally have higher initial capital costs and will require more space relative to the centrifugal pump or the rotary pump. The reciprocating pump will generally have higher maintenance costs relative to the centrifugal pump or the rotary pump. The centrifugal pump will generally have higher annual power consumption costs relative to the reciprocating pump or the rotary pump because of lower efficiencies. Costs Considerations : A pump that is selected for an application outside of its optimum operating parameters will almost certainly not follow these rules. For example, a rotary pump operating in a high pressure, abrasive-slurry service would probably have higher maintenance costs than a properly selected reciprocating pump. The close running clearances (particularly for high pressure service) required in the rotary pump would likely result in premature wear and frequent maintenance.
  • 37. AN INTRODUCTION TO PUMPING EQUIPMENT Centrifugal Pumps Fluid Handling: Centrifugal pumps are suitable for transferring a variety of fluids ranging from clean, clear non-abrasive fluids to abrasiveslurries. However, a centrifugal pump is not the best choice for pumping highly viscous fluids due to dramatic drops in efficiency at high viscosities. Centrifugal pumps are not normally specified for viscosities higher than about 4,000 SSU. Centrifugal pumps are also not well suited to pumping entrained air. Most centrifugal pumps can handle up to about 2% entrained gas and specially-designed pumps can handle up to about 10%. Reciprocating Pumps Fluid Handling: Reciprocating pumps are well suited for transferring clear, nonabrasive fluids, as well as abrasive slurries. In fact, the relatively low velocities of moving parts within a reciprocating pump make it particularly resistant to erosion in abrasive-slurry applications, provided that the pump is properly designed for the service. Reciprocating pumps maintain high efficiencies when pumping highly viscous fluids and can easily handle 50% and higher volumes of entrained gas.
  • 38. AN INTRODUCTION TO PUMPING EQUIPMENT Rotary Pumps Fluid Handling: Rotary pumps can also handle high viscosity fluids and high volumes of entrained gas. In fact, many rotary pumps operate at their best efficiency at higher viscosities. However, rotary pumps are not well suited for pumping corrosive fluids or fluids with abrasive solids because of close clearances between rotating and static pump components. Summary One fact that must always be remembered: A pump does not create pressure, it only provides flow. Pressure is a just an indication of the amount of resistance to flow. there are many different subcategories of pumps within these broad categories and there are many regions of overlap where multiple types of pumps in the same category and even in different categories would be suitable. Since every pump application is unique, each of the factors that influence the pump selection must be considered in detail.
  • 39. Learn how to have a successful job interview
  • 40. The fluid property, due to which, mercury does not wet the glass is A. surface tension B. viscosity C. cohesion D. Adhesion Laminar flow of a Newtonion fluid ceases to exist, when the Reynolds number exceeds A. 4000 B. 1500 C. 2100 D. 3000 The normal stress is the same in all directions at a point in a fluid, when the fluid is A. non-viscous. B. incompressible. C. both (a) and (b). D. having no motion of one fluid layer relative to the other. Head developed by a centrifugal pump depends on its A. speed B. impeller diameter C. both (a) and (b) D. neither (a) nor (b) Learn how to have a successful job interview
  • 41. In Centrifugal compressors, why does surge occurs? A. Surge occurs due to low pressure in the suction drum. B. Surge occurs due to low flow at suction. C. Surge occurs due to high speed. D. None of the above (neither A, nor B, nor C) Loading/unloading ethylene requires: A. Loading arm overhaul B. Loading arm dismantling C. Loading arm cooling-down D. None of the above (neither A, nor B, nor C) Why is pH measured in the boiler blowdown? A. To adjust the flow B. To prevent corrosion C. To inject detergent D. To inject polyelectrolyte What is the physical meaning of saturated steam? A. It is a steam at low pressure. B. Steam at Dew point or at a point where all water transferred to vapor. C. It is a steam at high pressure. D. None of the above (neither A, nor B, nor C) Sulphur dust is: A. Irritant & flammable B. Irritant and toxic C. Toxic D. Corrosive only Learn how to have a successful job interview
  • 42. Which of the following statement is not correct? A. Traceability of the product is optional B. Processes transform inputs into outputs C. Quality policy determines organisational objectives D. Efficiency is the relationship between result and resources In steam boilers, why is a continuous blowdown provided. A. To control level in steam boiler. B. To control the quality of steam. C. To control the pressure. D. All the above (A + B + C). What is the purpose of the fast purging in a steam boiler? A. To remove the sludge from the boiler bottom B. To replace part of the water with fresh make-up water C. To sample the water to check for composition D. To check the level inside the boiler drum Which of the following is not a quality principle? A. Customer focus B. Continuous improvement C. Process approach D. Maximum production on-specification How many carbon moles are in 6.00 g of C? A. Two moles. B. Three moles. C. Half mole. D. One mole. Learn how to have a successful job interview
  • 43. On process plants why are process/utilities connections equipped with flexibles and specific fittings? A. To make sure operator will recognize them B. To prevent any mix of utilities C. To facilitate the work of the operator D. To prevent purging with the wrong utility and/or hydrocarbon contamination In a distillation column, what is flooding? A. It is the level increase in the column. B. Pressure drop in the column. C. It occurs when the liquid/vapour traffic is disturbed due to high velocity of the vapour and liquid is entrained upwards. D. It occurs when the liquid/vapour traffic is disturbed due to low velocity of the vapour and liquid weeps through the plates. In a distillation column, what is the sensitive tray? A. It is the tray at which the feed to the column is placed in order to minimize temperature upsets. B. It is the tray at which temperature in the stripping section is controlled. C. It is the tray at which most of the light and heavy components are separated and fractionation occurs. D. None of the above (neither A, nor B, nor C) Learn how to have a successful job interview
  • 44. For centrifugal pumps, what is cavitation? A. Cavitation occurs due to low level in suction drum. B. Cavitation occurs when the NPSH available is less than the required NPSH. C. It is the presence of vapour in the suction drum. D. None of the above(neither A, nor B, nor C) Why is saturated steam used in the different reboilers in the plant and not superheated steam? A. To prevent corrosion B. To reduce reboiler duty C. To limit thermal exchange D. None of the above(neither A, nor B, nor C) For steam turbines, why is heating necessary before start up? A. To get more power. B. More discharge pressure. C. More speed. D. To avoid thermal shock. What is Latent Heat? A. It is the heat of a substance at ambient temperature. B. Heat required to vaporise or to condense a gas. C. Heat required to increase the temperature of 1 kg a substance by 1C. D. Heat required to melt or to freeze a liquid. Learn how to have a successful job interview
  • 45. What is Partial Pressure? A. It is the pressure of a substance at ambient temperature. B. Pressure required to vaporize or to condense a gas. C. It is the pressure of individual component in a mixture of gas. D. All the above (A + B + C). What is Boiling Point? A. It is the temperature required to vaporize the liquid. B. Pressure and temperature drop in the column. C. It is the temperature at which the vapour pressure of a liquid is equal to the atmospheric pressure. D. None of the above (neither A, nor B, nor C) The net positive suction head (NPSH) of a centrifugal pump is defined as the sum of the velocity head and the pressure head at the A. discharge. B. suction. C. suction minus vapor pressure of the liquid at suction temperature. D. discharge minus vapor pressure of the liquid at the discharge temperature. Pour point and freezing point is equal for A. petrol B. diesel C. water D. crude petroleum Learn how to have a successful job interview
  • 46. In cracking furnaces or fired heaters, what is the advantage of using excess air in combustion? A. Fuel consumption will be reduced. B. Temperature will be better. C. Complete combustion is ensured. D. All the above (A + B + C). Which of the following fractions of a crude oil will have the maximum gravity API (i.e. °API) ? A. Diesel B. Gasoline C. Atmospheric gas oil D. Vacuum gas oil Short distance transportation of grain, gravel, sand, ash, asphalt etc. is done by using a __________ conveyor. A. flight B. slat or drag C. ribbon D. screw Friction factor for fluid flow in pipe does not depend upon the A. pipe length. B. pipe roughness. C. fluid density & viscosity. D. mass flow rate of fluid. Learn how to have a successful job interview
  • 47. Which one of the following is incombustible ? A. H2 B. C2H2 C. CCl4 D. S Fog is an example of colloidal system of A. solid dispersed in gas. B. solid dispersed in liquid. C. liquid dispersed in gas. D. gas dispersed in liquid. In troposphere (the weather domain), the temperature 't' at height 'h' above the sea level in metres is given by (where, temperature at sea level is 15°C and t is in °C.) A. t = 15 - 0.0065 h B. t = 15 + 0.0065 h C. t = 0.0035 h - 15 D. t = 15 - 0.0035 h A high pressure boiler generates steam at a pressure greater than __________ kg/cm2 . A. 10 B. 50 C. 30 D. 80 Which of the following is not categorised as a "mechanical operation" ? A. Agitation B. Filtration C. Size enlargement D. Humidification Learn how to have a successful job interview
  • 48. What is the kind of the following valve ? slide valve gate valve expansion valve wafer check valve Learn how to have a successful job interview
  • 49. What is the kind of the following valve ? needle valve Foot valve non return valve or one way valve or check valve Butterfly Valve Learn how to have a successful job interview
  • 50. Send your question and we will post it on our page wall
  • 51. LIST of QUESTIONS 1. i wanna attempt to construct a viable home based ammonia or urea production unit. using methane or LPG. In your opinion, is this possible to do profitably? And if it is cud u send me links to some literature that may help me out. Thanks in advance 2. If there any chemical which when mixed with water gives specific density higher than if water was mixed with Baryte? 3. What is yield of a process ? 4. What are differences between HETP and HTU for column 5. could you give me some information for the glycerin process 6. Difference between total dead heat & dead head at max. impeller centrifugal pump 7. Is stichoimetry compulsory for chemical engineering ? 8. dose the activation energy change with particle size when finding the rate equation? or in another way dose the activation energy affect with the particle size when finding the rate equation? 9. What chemical reaction not exothermic or endothermic or third way is possible or not ? 10. I want references about bio gas plz 11. how to prepare organic fertilizer at home from domestic waste? Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 52. LIST of QUESTIONS 12. if non condensable is added inthe distillation column , so what's the effect in the dew point of the distillate . .whether it will increase or decrease? And why 13. What is the cheapest form of polymer? 14. What is the difference between a simple and long chain polymer? 15. can any one help me to find information about Harriot method for calculation of diffusion coefficient 16. what is the MAX temperature allowable for a heat exchanger AS CWS COOLING WATER SUPPLY ? 17. can you give me references for production of dimethyl ether 18. What role does the Ventury effect have on mixing chemicals? 19. How can i check the purity of Kcl? 20. Which chemical will you add to water to increase the viscocity to 40 centipose? 21. Esterification reaction is endothermic or exothermic? 22. can u suggest me whether chemical engg. Hv scope in India...? 23. What is the difference between extensive and intensive properties ? 24. can u explaine about split type heat exchanger 25. How much water occupy in a 1" inch s.s pipe of length 10 meter ??? How can we calculate? Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 53. LIST of QUESTIONS 26. What is wet vacuum and dry vacuum and compare both 27. why hydrogen is exception for joule thomson effect? 28. i want to know where the distillation coulumn will be used in a horizontal position? and how will be the operating conditiones? 29. Can we use CSTR for gaseous reactant ? 30. Can we use liquid DAP instead of granules? As it will reduce the cost of granulation,drying, cooling 31. Would you please tell me what is the maximum suction head for centrifugal pump in case of negative suction?? 32. xplain d principles of the heat xchanger wen fluid flows counter currently 33. how nuclear fusion and fission will takes place at a time in hydrogen bomb? 34. uses of vinyl sulphone ester ? Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 54. Tawedzerwa Masuka i wanna attempt to construct a viable home based ammonia or urea production unit. using methane or LPG. In your opinion, is this possible to do profitably? And if it is cud u send me links to some literature that may help me out. Thanks in advance Name comment Ah.yehia this attach will help you http://www.mediafire.com/download/w 7ftn158rtbinx3/ammonia.rar Nidhi Satwara If there any chemical which when mixed with water gives specific density higher than if water was mixed with Baryte? Name Er Dhaval Patel comment Molybdenum sulphate with solution pH 4-5. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 55. Atul Gourh What is yield of a process ? Name Ah.yehia comment The yield of a chip manufacturing process refers to how much salable product is able to be produced. This can be an absolute number (chips per day for example) or a factor that refers to the percentage of total chips manufactured that passed inspection and were able to be sold. Of course, the higher the yield, the more chips that can be produced for (basically) the same cost, which allows costs and hence prices to decrease. http://www.pcguide.com/ref/cpu/char/mfg Yield-c.html http://www.sixsigmatraining.org/six-sigmaprojects/how-to-calculate-processyields.html Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 56. Atul Gourh continue What is yield of a process ? Name comment Ah.yehia A manufacturing process has a 70% yield, meaning that 70% of the products are acceptable and 30% are defective Abdelrahman Mohamed Khalid i think yield means that the product we need & and remaining byproducts aren't important like the main one. Mohamed Wageeh amount of desired product/amount of undesired product(from side reaction) or even from a single step reaction.. but Hussam Nabawy in this case a yield of a reaction will express the conversion!! Naveed Ali Koondhar Saad Raad Simply we can say the rate of production the desired material(product)/total material(feed) Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 57. Atul Gourh continue What is yield of a process ? Name comment the yield is simply what we have got as a product at the end of the process. Yuosuf Al Faraj yield is related to the product while conversion related to the reactant . Syed Shah Jehan Gillani MEASURE OF PRODUCTIVITY HOW EFFICIENTLY GETTING THE THEORETICAL MAX.POSSIBLE OUTPUT BY GIVING SPECIFIC INPUT Mohamed Hassn Waheed I think it is the percentage of conversion from input raw material to the main product Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 58. Tarkeshwar Pandey What are differences between HETP and HTU for column Name comment Nickkhil Batra hetp =height eqivalent to theoretical stage .it is height of packing that provides seperation equal to tray Nickkhil Batra whereas htu is height of transfer unit which shows seperation efiiceincy of packinh Prince Singla Nickkhil: if HETU=HTU then wat u interpret about operating line and equilibrium line.....means are they coincide or // or perpendicular...?? Nickkhil Batra i think operating lines are parallel in that case Zé Maurício Jawwad Khan Er Dhaval Patel HETP/HTU=eficiciency HETP is generally used for distillation.. And HTU for gas absorption or stripping.... Hetp=shows height of theorytical stages &htu=shows that height of colum Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 59. Ivan Montiel could you give me some information for the glycerin process Name comment Abdallah ELGharbawy glycerin can be produced via two routes : the first one from oil and fats by reaction of oil with alchol (methanol & ethanol ) and then we get biodiesel and glycerol Abdallah ELGharbawy the second routes from chlorination of propylene to give allyl chloride, which is oxidized with hypochlorite to dichlorohydrins, which reacts with a strong base to give epichlorohydrin. Epichlorohydrin is then hydrolyzed to give glycerol. Chlorine-free processes from propylene include the synthesis of glycerol from acrolein and propylene oxide. Er Dhaval Patel Glycerine is bye product of soap mfg and produce of fat or oile Prejilesh Vanimel Triglycerides of fatty acid(oil) can split into fatty acid &glycerin with high temprature&pressure Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 60. Mohit Tiwari Difference between total dead heat & dead head at max. impeller centrifugal pump Name comment You can deadhead a centrifugal pump if you operate it full of liquid with the inlet and outlet valves closed, so there is no flow through the pump. In this case, the rotating component of the pump (impeller) will continue to agitate the same volume of liquid. Ah.yehia Danger The danger of deadheading a centrifugal pump is that, as the liquid rotates, frictional forces cause its temperature to rise to the point where it vaporises. The vapour disrupts cooling of the pump and may cause excessive wear and tear to its bearings. Deadheaded centrifugal pumps have been known to explode even if they contain just water or brine. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 61. Mohit Tiwari continue Difference between total dead heat & dead head at max. impeller centrifugal pump Name comment Ah.yehia Protection A centrifugal pump can be protected from the effects of deadheading by fitting a line, upstream of the outlet valve, to recycle liquid back to the inlet valve. The diameter of the line should be sufficient to recycle enough liquid to prevent the pump overheating. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 62. Faizan Arshad Is stichoimetry compulsory for chemical engineering ? Name Narendra Naren Kumar comment s it's important Duraisamy s ofcourse. Gopalakrishnan Devendra Gurjar Muneeb Ur Rahman Junaid Ahmed Yes Yes as it helps to achive desired product details. As well as it izs the basis for mass and heat transfer calculations which are used to design equipments. yes Er Dhaval Patel Yes it is important Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 63. Edmon A. Qusar dose the activation energy change with particle size when finding the rate equation? or in another way dose the activation energy affect with the particle size when finding the rate equation? Name comment Mohit Tiwari I think it is only function of temperature hence will not change with particle size Jama Salimov students opinion: activation energy can be calculated using Arrhenius equation, which is k=-A*e^(-Ea/RT) I don't see a direct correlation, but increased particle size will give smaller mass transfer area, hence heat transfer area will be lowered, which indirectly impacts rate of equation. I doubt there is a strong impact. Mohit Tiwari I think particle size matters in collision theory as it reduces the no. of affecting collision of all particles hence reduction in temp & rate reaction but no effect in consideration for arrhenius equation Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 64. Edmon A. Qusar continue dose the activation energy change with particle size when finding the rate equation? or in another way dose the activation energy affect with the particle size when finding the rate equation? Name comment Large particle size as per collision theory Mohit Tiwari will reduce the kinetic energy & hence activation energy Malus Prathmesh nope activation energy will not chnge...mohit correctly pointed out.....it is a function of temperature Abdallah ELGharbawy activation energy only depend on temperature Muneeb Ur Rahman In collision theory, formation of products takes place when reactant molecules collide with a certain minimum energy to form product molecules. Hence at same temperature more energy is required by bigger molecule to move and collide compared to smaller one. Therefore activation energy is more for bigger molecule at constant temperatue. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 65. Gokul singh What chemical reaction not exothermic or endothermic or third way is possible or not ? Name comment * An endothermic reaction is any chemical reaction that absorbs heat from its environment. Here's a list of examples of endothermic reactions. You can use these when asked to cite an example or to get ideas to set up a demonstration of an endothermic reaction or process. Ah.yehia * Endothermic Chemical Reactions reaction of barium hydroxide octahydrate crystals with dry ammonium chloride dissolving ammonium chloride in water reaction of thionyl chloride (SOCl2) with cobalt(II) sulfate heptahydrate mixing water and ammonium nitrate mixing water with potassium chloride reacting ethanoic acid with sodium carbonate photosynthesis (chlorophyll is used to react Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 66. Gokul singh continue What chemical reaction not exothermic or endothermic or third way is possible or not ? Name comment Endothermic Chemical Reactions carbon dioxide plus water plus energy to make glucose and oxygen) Endothermic Processes Ah.yehia * These examples could be written as chemical reactions, but are more generally considered to be endothermic or heat-absorbing processes: melting ice cubes melting solid salts evaporating liquid water converting frost to water vapor (melting, boiling, and evaporation in general are endothermic processes) making an anhydrous salt from a hydrate forming a cation from an atom in the gas phase splitting a gas molecule separating ion pairs cooking an egg baking bread Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 67. ‫اسالم احمد غانم‬ I want references about bio gas plz Name Michał Kisielewski comment http://www.amazon.com/Biogas-WasteRenewable-ResourcesIntroduction/dp/3527327983 Selvavinayagam Santhanam how to prepare organic fertilizer at home from domestic waste? Name Abdallah ELGharbawy Gokul Singh comment by anaerobic digestion Like a composte, we take a large chamber and biodegradable waste collect in this chamber, add water in this chamber, and aerobic and anaerobic degration take place, the reaction enffluent or product use as a organic fertiliser. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 68. Sahil Satwara if non condensable is added inthe distillation column , so what's the effect in the dew point of the distillate . .whether it will increase or decrease? And why Name comment Peto Wagih Look, I'm not sure of my answer but dew point is the point at which the first drop of liquid appears, So assuming that there is no chemical reaction between the non condensing material added and the existing material and also assuming the same pressureand temperature applied, I don't see a reason why should dew point change in the first place....I mean, it is function of pressure and temperature in the first place so by not changing these factors all what changes is the "amount" of liquid not "dew point". Ahmed Yehia i think it has no effect ĀĥMệd HĀşşan INCREASES DUE TO INCREASE IN PRESSURE !! Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 69. Sahil Satwara continue if non condensable is added inthe distillation column , so what's the effect in the dew point of the distillate . .whether it will increase or decrease? And why Name comment Mohit Tiwari When vapor condenses in condenser of column @dew point provide a wet surface but then non condensable surrounds this surface & then vapor will first diffuse through this film of non condensable (additional gas phase resistance) which provide resistance to vapor reaching towards dew point hence dew point increases & load of condenser increase & therefore reflux ratio decreases & hence will be requirement of more no. of trays in enriching section of column. Mohit Tiwari as i think non condesable provide resistance to vapor i.e work like inert & there will be problem in phase transfer from bubble pt. to dew point Osama Abdallha decreases because of high pressure which will be developed Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 70. Sahil Satwara continue if non condensable is added inthe distillation column , so what's the effect in the dew point of the distillate . .whether it will increase or decrease? And why Name Abo Gooda Clint Regondola Mohammed Zé Maurício comment I think it will decrease increases due to Dalton's and Raoult's law pi dec. (Dalton); xi dec. (Raoult); then yi inc. and dew point increase. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 71. Nidhi Satwara What is the cheapest form of polymer? Name Zeeshan Amjad Malhi Abdelrahman Mohamed Khalid Alexander John Rico Jeevarathnam Joseph Raghu Can Can Tulio Yterbio Fernandes Vale Harish Ch Gokul Gokz SaintYago Pincay Gopal Danu comment polythene linear polymer polyethylene Polythene polythene It's polyethen polystyrene polyethen polyethylene is the most economic globally 1polyethylin Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 72. Nidhi Satwara What is the difference between a simple and long chain polymer? Name comment Manne Nirmal Kumar A simple polymer consists of a long chain of monomers joined by covalent bonds Polymers are repeating units of atoms that form a chain, as the length of this chain increases, the polymers molecular weight increases. Zeeshan Amjad Malhi Simple polymers are by definition then, short chain, low atoms per molecule, structures. Longer chains equal larger molecular weight polymers. Longer chains incorporate polymers with a lot more diversity in applications, like high density plastics with high melting temperatures, abrasion resistance (rubber , urethanes and such) Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 73. Nidhi Satwara continue What is the difference between a simple and long chain polymer? Name comment Mohamed Serag Eldeen if u ask about measuring? it must have higher viscosity Er Dhaval Patel Simple polymer contain only 1monomar but chain polymer contain monemar in series. Yucef Tawes can any one help me to find information about Harriot method for calculation of diffusion coefficient Name Abhilash Narnaware comment www.sciencedirect.com u can search here Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 74. AhMed HAssan what is the MAX temperature allowable for a heat exchanger AS CWS COOLING WATER SUPPLY ? Name comment Krunal Shah It's depends on the condition...in hot conditions It is around 55C to 60C Zé Maurício Sana Ullah Mustafa M Hathal Alfukaiki Yuosuf Al Faraj Raghu Can Can Mohamed Serag Eldeen Robin Pv It depends on plant and local it's not fixed dew point we usually supply cooling water at 35C, so i think the max temperature will be 40 to 45. i think up 2 its bubble point bubbling point i thnk it is 30 Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 75. AhMed HAssan continue what is the MAX temperature allowable for a heat exchanger AS CWS COOLING WATER SUPPLY ? Name comment answer 50c as more than this calcium carbonate and potassium carbonate may accumulated AhMed HAssan again and make fouling probs.tand corrosion prob. ref:Guide to process equipment book ‫رامي الحسن‬ can you give me references for production of dimethyl ether Name Sana Ullah comment Turton,R.et al : Analysis, Synthesis and design of Chemical Processes, 1998. Page Number 709 to 711 Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 76. Nidhi Satwara What role does the Ventury effect have on mixing chemicals? Name comment Azhar Mushtaq it decrease the effect of pressure and increase the mixing of chemical Zé Maurício speeding velocity Muneeb Ur Rahman Reduces mixing time Nidhi Satwara How can i check the purity of Kcl? Name Tulio Yterbio Fernandes Vale Amr Waly Zé Maurício Er Dhaval Patel comment Volumetric analisys acid/base titration vs NaOH Constant current coulometry and ion chromatography to subtract bromide Colaromatry titration Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 77. Nidhi Satwara Which chemical will you add to water to increase the viscocity to 40 centipose? Name comment Utpal Pohane polyacrylamide & XANTHANUM GUM Er Mayur Patil i think..........polyacrylamide or xanthanum gum is right ans... Santosh Kumar Bhavirisetti PEG Hasan Salamah carpobol Yuosuf Al Faraj agar, but the question is what is the fraction of agar should be added to raise water viscosity to 40 cintypose? Gagan Deep Kalra Dheeraj Kumar Yarlagadda Er Kapil Maan Josue Mateus Bohn Agar agar is rite answer polyacrylamide Agar agar sol is the mixture of various carbohydrates Agar Agar Himanshu Sharma I thnk it is agar agar solution Abhishek Verma honey Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 78. Zafir Imam Esterification reaction is endothermic or exothermic? Name Alaa Khaled Meetkees Gokul Singh Koushik Aguan comment exothermic Endhothermic reaction, and reversible, water formation take place, it is major to remove it, otherway potential got backward direction endo Sanjay Khatri Exothermic rxn Moni Velasco levemente endotermica Ronak Raiyani It is mainly exothermic reactions but when the esterification generates a cyclic ester they tend to be endothermic reaction...! Shraddha Deshmukh Jeevarathnam Joseph endothermic Endothermic reaction. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 79. Zafir Imam continue Esterification reaction is endothermic or exothermic? Name comment Nimit Vasani Endothermic....beacuse u need heat to evaporate water from alcoholic group Hiren Gohil endothermic. Er Dhaval Patel Endothermic reaction Roshan Tembhurne Endothermic dude Kiran Bhatreja Exothermic reactn Faisal Panhwar Endo. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 80. Trisha Sharma can u suggest me whether chemical engg. Hv scope in India...? Name comment Usman Naseem Yes Gutka is a Chemical, you can have your own gutka stall at Railway station.. Prathap Selvam no scope.. Anil Kumar Really no scope at all Brijesh Rana nt for girls......... really Sachin Chavare scope is what? how you take challenge is scope...n India has very big scope for Chemical Engineers...All the best. Nirali Rana Yes...lots of scope...depends on u n ur knowlage. Roshan Tembhurne Lots of Vishnu Soman Kannankara Of course yes....! but it only depends upon u. Mohit Sharma Yes Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 81. Abhishek Verma What is the difference between extensive and intensive properties ? Name comment Engr Muhammad Ali intensive properties are independent of mass while extensive depends upon mass Arthur J Shih If you cut a system in half, quantities that change are extensive, and quantities that don't change are intensive. Ronak Raiyani An intensive property is one whose value does not depends on the amount of the substance for which it is measured.i.e: Temp.,Sp.Gravity,Atm.Pressure etc. while, Extensive is one that value depends on quantity of matter in the system.i.e.;Entropy,Enthalpy,Volume, Gibbs Energy etc. Er Dhaval Patel Intensive properti independent of mass&extensive property bepend on mass Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 82. Abhishek Verma continue What is the difference between extensive and intensive properties ? Name comment Taha Siddiqui extensive property do not depends upon mass while expensive does Er Kapil Maan Intensive property are bulk property means physical properties of system bt the extensive are interacting the subsystem Hasan Salamah in. depends on mass while exdoeant depend on mass Vishnu Soman Kannankara Omar Samir Intensive-independnt of mass Hence all specific properties are intensive Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 83. Raghu Can Can can u explaine about split type heat exchanger Name comment the manufacturer of all types of Split Type Steam Heat Exchanger For Rice Parboiling Plant. it is engaged in the production and distribution of premium quality Split Type Steam Heat Exchanger For Rice Parboiling Plant in the industry. These Heat Exchangers we supply in the market is known for it high precision performance. In case tube leakages in heat exchanger, Rajashekar every tube Is repairable in your mill Chilukamari Cleaning system is very comfortable, open to the framing both and cleaning the every tube Steam goes to the multiple header instead of standard type one header that increase efficiency of heat exchanger & then reduces the drying time and save the husk In case lot of tubes leakages in Heat exchanger, remove only leakage part and join the new part. No need to change total heat exchange Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 84. Kavi Arasu How much water occupy in a 1" inch s.s pipe of length 10 meter ??? How can we calculate? Name comment Think of the pipe as a cylinder, volume of cylinder is pi*r^2*h where h will be 10 m, Muhammad radius would be the innder radius of the 1 Usman inch pipe by the way. Volume would be how much water can that pipe occupy Mohammed volume=3.14*r^2 *h Salih Koushik Agarwal 5064.5 cc Hemant Rautela 5.064506 liters of water Pandurang Chate Pi/4 X d X d X L... d is inner diameter Zé Maurício 5 L, uff. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 85. Raghu Can Can What is wet vacuum and dry vacuum and compare both Name comment Nitin B Sasane vaccum containing moisture is wet vaccum. and no misture available is dry vaccum. Ahmed Yehia * i think dry vacuum that happened where complete separation between vapors and liquids so vacuum will occur in gas phase 100% * on the other hand, wet vacuum happened in gas fraction phase mean media is vapors and some liquids * i don't sure that Anbarasan Sankaran Raghu Can Can Liquid particle present that is wet vacum. There no liquid particle it is dry vacum. Wet vacuum means in ejector if we use steam and create vacuum means that is wet vacuum neither we use air means that is dry vacuum but I don't know why they r using wet r dry vacuum Murthy Meduri Balaji Use of steam differentiate both Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 86. Dinakar Satya why hydrogen is exception for joule thomson effect? Name comment Ahmed Mohamed Khalil At room temperature, all gases except hydrogen, helium and neon cool upon expansion by the Joule–Thomson process. the exception for hydrogen, helium and neon is due to (the very low inversion temperatures) of them which is -68°C for H2,−222 °C for helium at Atm pressure. this make them warm up when expanded at constant enthalpy at typical room temperatures. Djohan Khairudin When release to atmospheric pressure,it heats up. Molecular interaction too weak. Helium, Neon and hydrogen are tree gases whose Joule–Thomson inversion temperatures at a Zé Maurício pressure of one atmosphere are very low (e.g., about 51 K (−222 °C) for helium). Thus, they warm up when expanded at constant enthalpy at typical room temperatures. Raghu Can Can these hydrogen and helium r more reactive groups Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 87. Dinakar Satya continue why hydrogen is exception for joule thomson effect? Name comment Anup Ca bcz of -ve joule thomsn coefficient....that means :increase itz(H2)temp in throatling process. Ronak Raiyani & More cheaper than argon, krypton, xenon, niyon etc Becoz it is noble gas. Nirav Gandhi Hydrogen is not follow joul thomson effect iir reversible Anup Ca Helium is an another example. Fabio Augusto Hydrogen is an exception in a certain range of P and T, but it is not the only exception. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 88. Dinakar Satya i want to know where the distillation coulumn will be used in a horizontal position? and how will be the operating conditiones? Name comment It's possible, but it's not feasible. The reason why distillation columns are vertical is so that (1) gravity can pull the liquid phase downward and (2) trays/packing will allow adequate contact of the liquid and vapor phases. Arthur Shih Suraj Chaudhari Horizontal distillation columns will not only require two extra pumps (one for the vapor and one for the liquid, because gravity cannot provide the energy anymore), but it will also need some sort of mechanism to maximize contact between the vapor and liquid phases. When the distillation column is vertical, gravity and trays/packing achieves both of these. What....am not heard before this... Do anybody used distillation kettle in horizantal plane...? No its not possible Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 89. Dinakar Satya continue i want to know where the distillation coulumn will be used in a horizontal position? and how will be the operating conditiones? Name comment Arthur Shih I also want to point out that vertical towers also save valuable land space. One disadvantage of vertical towers is that it requires more piping (you need to pump the tops product all the way down the length of the pipe to the condensers), but the advantages greatly outweigh the disadvantages which is why they've become the "standard" in the past 100 years. Suraj Chaudhari What....am not heard before this... Do anybody used distillation kettle in horizantal plane...? No its not possible Er Dhaval Patel Itis practical not feasiable Zé Maurício At space, rotating! Mohammed as used in oil refineries Salih Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 90. Atul Gourh Can we use CSTR for gaseous reactant ?? Name comment Nirali Rana Generaly CSTR is used for uniform mixing n in gasious reactant its hard to mk perfact mixing..before mixing day react...so PFR is more preffrable...according to me. Hasan Salamah it's better to use PFR Nafees Ahmad yes some time, in the presence of media (liquid)...i.e HDPE process Er Dhaval Patel Yatai Mike No Ajit Salve Vivek Shukla no Rita Youfa no, cstr 4 liq-liq or solih-liq Antreas Koumouris Mohamed Serag Eldeen Davey Uloma we use them for slow liquid phase rxns mostly NOP Ghaith Alsaidi No Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 91. Murthy Meduri Balaji Can we use liquid DAP instead of granules? As it will reduce the cost of granulation,drying, cooling Name Bujji Fireheart Salahuddin Rajput comment ya bt bt the cost depends on farmers farmer lost so much of monney its not gud product for farmer and handling too hard calculation is too confused for former *Difficult to calculate (Dilution Required) *Poor Handling *Consume too quickly (Drawback) *it will stay on the leafs (can harm/damage the leaf) due to excess nitrogen *granule release adequate amount in particular time while liquid spills and absorbs quickly by the soil. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 92. Saurbh Salfale Would you please tell me what is the maximum suction head for centrifugal pump in case of negative suction?? Name Suraj Chaudhari Anup Ca Pravin Patil Syed Shah Jehan Gillani Saurabh Salfale Yatish Banakar comment Jit Sumon 10.30 bar 10.33 m water 10.33 m water (34 feet) 10 m But i need an explaination over this... I think it may related with the concept of vapour pressure of the pumping fluid bcoz when vapour pressure of the pumping fluid is equal to atm. press then cavitation will takes place due to boiling. For 1kg/cm2 it will give 10.33mts head, section wil play important role during starting of pump.. If negetive need to give priming. When vp is equal atm then boiling takes place Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 93. Bright Izuchukwu xplain d principles of the heat xchanger wen fluid flows counter currently Name comment Sanjay Khatri A device is used for exchanging or transfering energy heat between the fluids. if fluid in counter current den heat trnsfer take place will be more bcoz of counter Chiràg current fluid directin n residence time Mahyavanshi between two fluid will b mor.so it creat high ht n low require energy. Er Rajvi Garg heat transfer co-efficient will be more if the flow is counter current heat transfer will be more , contact tym is Vibha Mishra more heat loss wiil be less and heat transfer coefficient will be more. Pandurang Chate Heat is getting transferred from hot fluid to cold fluid. Being counter current flow, area of heat exchanger is much lower than cocurrent flows becuase of higher LMTD(Log Mean Temperature Difference) Zé Maurício The coolant can get hotter than the fluid cooled. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 94. Bright Izuchukwu continue xplain d principles of the heat xchanger wen fluid flows counter currently Name comment Mohamme heat is transferred in three different ways, d Salih conduction,convection,and radiation There is more contact surface area nd contact Suraj time for exchange the heat and low exotherm Chaudhari nd optimum operational cost Sha Geck @mohammed salih: heat exchangers exchange heat between the process fluid and cooling fluid by means of conduction and convection.. Not by radiation..! Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 95. Dinakar Stya how nuclear fusion and fission will takes place at a time in hydrogen bomb? Name comment Mohamed Ahmed Fouad The energy required for nuclear fusion comes from uranium splits which results in fussion and release a large amount of energy. So, in hydrogen bomb nuclear fission of uranium first takes place then nuclear fusion of Deuterium and tritium takes place. Nidhi Satwara uses of vinyl sulphone ester ? Name Er Dhaval Patel comment It is used as intermideate in dyes stuf industry. Send your question and we will post it on our page wall ONE of page fans has a question and needs an answer
  • 96. https://www.facebook.com/IamCheEng Designed by Ah.Yehia 2013

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