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  1. What is meant by catalytic cracking? Give an example where it is used? You can Answer this question Like the best answer Share to get more answers
  2. Section 3. Classification and Method of Sale of Petroleum Products General Considerations Automotive Gasoline and Automotive Gasoline-Oxygenate Blends Posting of Antiknock Index Required -- All automotive gasoline and automotive gasoline-oxygenate blends shall post the antiknock index in accordance with applicable regulations, 16 CFR Part 306 issued pursuant to the Petroleum Marketing. When the Term "Leaded" may be Used -- The term "leaded" shall only be used when the fuel meets specification requirements.[13] Use of Lead Substitute must be Disclosed -- Each dispensing device from which gasoline or gasoline-oxygenate blends containing a lead substitute is dispensed shall display the following legend: "Contains Lead Substitute." The lettering of this legend shall not be less than 12 mm (1/2 in) in height and the color of the lettering shall be in definite contrast to the background color to which it is applied. Nozzle Requirements for Leaded Fuel -- Each dispensing device from which gasoline or gasoline-oxygenate blends that contain lead in amounts sufficient to be considered "leaded" gasoline, or lead substitute engine fuel, is sold shall be equipped with a nozzle spout having a terminal end with an outside diameter of not less than 23.63 mm (0.930 in).[11] of Terms -- It is prohibited to use specific terms to describe a grade of gasoline or gasoline-oxygenate blend unless it meets the minimum antiknock index requirement shown in Table 1 Method of Retail Sale -- Type of Oxygenate must be Disclosed. -- All automotive gasoline or automotive gasoline-oxygenate blends kept, offered, or exposed for sale, or sold at retail containing at least 1.5 mass percent oxygen shall be identified as “with” or “containing” (or similar wording) the predominant oxygenate in the engine fuel. For example, the label may read “contains ethanol” or “with MTBE.” The oxygenate contributing the largest mass percent oxygen to the blend shall be considered the predominant oxygenate. Where mixtures of only ethers are present, the retailer may post the predominant oxygenate followed by the phrase “or other ethers” or alternatively post the phrase “contains MTBE or other ethers.” In addition, gasoline-methanol blend fuels containing more than 0.15 mass percent oxygen from methanol shall be identified as “with” or “containing” methanol. This information shall be posted on the upper 50 percent of the dispenser front panel in a position clear and conspicuous from the driver’s position in a type at least 12.7 mm (½ in) in height, 1.5 mm (1/16 in) stroke (width of type).(Amended 1996).[1] Documentation for Dispenser Labeling Purposes -- The retailer shall be provided, at the time of delivery of the fuel, on an invoice, bill of lading, shipping paper, or other documentation, a declaration of the predominant oxygenate or combination of oxygenates present in concentrations sufficient to yield an oxygen content of at least 1.5 mass percent in the fuel. Where mixtures of only ethers are present, the fuel supplier may identify either the predominant oxygenate in the fuel (i.e., the oxygenate contributing the largest mass percent oxygen) or, alternatively, use the phrase “contains MTBE or other ethers.” In addition, any gasoline containing more than 0.15 mass percent oxygen from methanol shall be identified as “with” or “containing” methanol. This documentation is only for dispenser labeling purposes; it is the responsibility of any potential blender to determine the total oxygen content of the engine fuel before blending.[13] Diesel Fuel Labeling of Grade Required. -- Diesel Fuel shall be identified by grades No. 1-D, No. 1-D (low sulfur), No. 2-D, No. 2-D (low sulfur), or No. 4-D. Each retail dispenser of diesel fuel shall be labeled according to the grade being dispensed except the words "low sulfur" are not required.[13] Location of Label. -- These labels shall be located on the upper 50 percent of the dispenser front panel in a position clear and conspicuous from the driver’s position, in a type at least 12 mm (1/2 in) in height, 1.5 mm (1/16 in) stroke (width of type).[1] Labeling Properties of Premium Diesel -- All retail dispensers identified as premium diesel must display either: A label that includes all qualifying parameters as specified in Premium Diesel Fuel affixed to each retail dispenser. The label shall include a series of check boxes clearly associated with each parameter. The boxes for the parameters qualifying the fuel must be checked. All other boxes shall remain unchecked. The marketer may check as many boxes as apply, or A label that includes only the parameters selected by a marketer to meet the premium diesel requirements as specified in 2.2.1. Premium Diesel Fuel. In either case, the label must display the following words: X "Premium Diesel Fuel" in a type at least 12 mm (1/2 in) in height by 1.4 mm (1/16 in) stroke (width of type). When applicable, as determined by the label option and qualifying parameters chosen by the marketer, the label must also display the following information and letter type size:- X The words "Energy Content," "Cetane Number," "Low Temperature Operability," "Thermal Stability," and "Fuel Injector Cleanliness" in a type at least 6 mm (1/4 in) in height by 0.75 mm (1/32 in) stroke (width of type).[11,13] X A declaration of the minimum Energy Content (minimum 38.65 MJ/ L gross [138,700 BTU/gallon]), if energy content is chosen as a qualifying parameter, in type at least 3 mm (1/8 in) in height by 0.4 mm (1/64 in) stroke (width of type). X The minimum cetane number guaranteed (at least 47.0) if cetane number is chosen as a qualifying parameter, in a type at least 3 mm (1/8 in) in height by 0.4 mm (1/64 in) stroke (width of type). X The date range of low temperature operability enhancement, (e.g., October March,) along with the qualifying test method (ASTM D 4539 or ASTM D 2500), if low temperature operability is chosen as a qualifying parameter, in a type at least 3 mm (1/8 in) in height by 0.4 mm (1/64 in) stroke (width of type). For Example :- Premium Diesel Fuel High Energy Content Cetane Number, 47.0 min Low Temperature Operability (Oct.-Mar.,LTFT) Thermal Stability Fuel Injector Cleanliness or Premium Diesel Fuel Cetane Number, 47.0 min Low Temperature Operability (Oct.-Mar., LTFT) Thermal Stability X The label must be conspicuously displayed on the upper half of the product dispenser front panel in a position that is clear and conspicuous from the driver’s position.(Added 1998) (Amended 1999) Delivery Documentation - Before or at the time of delivery of premium diesel fuel, the retailer or the wholesale purchaser consumer shall be provided on an invoice, bill of landing, shipping paper, or other documentation a declaration of all performance properties that qualifies the fuel as premium diesel fuel as required in (Added 1998) (Amended 1999) Aviation Turbine Fuels Labeling of Grade Required: Aviation turbine fuels shall be identified by Jet A, Jet A 1, or Jet B. NFPA Labeling Requirements also Apply Each dispenser or airport fuel truck dispensing aviation turbine fuels shall be labeled in accordance with the most recent edition of National Fire Protection Association NFPA 407, "Standard for Aircraft Fuel Servicing." NFPA 407, 1990 Edition: Section 2 3.18 Product Identification Signs. Each aircraft fuel servicing vehicle shall have a sign on each side and the rear to indicate the product. The sign shall have letters at least 3 inches (75 mm) high of color sharply contrasting with its background for visibility. It shall show the word "FLAMMABLE" and the name of the product carried, such as "JET A," "JET B," "GASOLINE," or "AVGAS." [14] Aviation Gasoline Labeling of Grade Required: Aviation gasoline shall be identified by Grade 80, Grade 100, or Grade 100LL. NFPA Labeling Requirements also Apply: Each dispenser or airport fuel truck dispensing aviation gasoline shall be labeled in accordance with the most recent edition of National Fire Protection Association (NFPA) 407, "Standard for Aircraft Fuel Servicing." NFPA 407, 1990 Edition: Section 2 3.18 Product Identification Signs. Each aircraft fuel servicing vehicle shall have a sign on each side and the rear to indicate the product. The sign shall have letters at least 3 inches (75 mm) high of color sharply contrasting with its background for visibility. It shall show the word "FLAMMABLE" and the name of the product carried, such as "JET A," "JET B," "GASOLINE," or "AVGAS." Fuel Oils Labeling of Grade Required Fuel Oil shall be identified by the grades of No. 1, No. 2, No. 4 (Light), No. 4, No. 5 (Light), No. 5 (Heavy), or No. 6. Kerosene (Kerosine) Labeling of Grade Required: Kerosene shall be identified by the grades No. 1-K or No. 2-K. Additional Labeling Requirements: Each retail dispenser of kerosene shall be labeled as 1-K Kerosene or 2-K. In addition, No. 2-K dispensers shall display the following legend "Warning - Not Suitable for use in unvented heaters requiring No. 1-K." The lettering of this legend shall not be less than 12 mm (1/16 in) in height by 1.5 mm (1/16 in) stroke; block style letters and the color of lettering shall be in definite contrast to the background color to which it is applied.[14] Fuel Ethanol Fuel ethanol shall be identified by the capital letter E followed by the numerical value volume percentage. Retail Dispenser Labeling: Each retail dispenser of fuel ethanol shall be labeled with the capital letter E followed by the numerical value of volume percent denatured ethanol and ending with the word "ethanol." Additional Labeling Requirements:Fuel ethanol shall be labeled with its automotive fuel rating in accordance with 16 CFR Part 306.[14] Fuel Methanol How Fuel Methanol is to be Identified: Fuel methanol shall be identified by the capital letter M followed by the numerical value volume percentage of methanol. Retail Dispenser Labeling Each retail dispenser of fuel methanol shall be labeled by the capital letter M followed by the numerical value volume percent and ending with the word "methanol." Liquefied Petroleum (LP) Gas How LPG is to be Identified: Liquefied petroleum gases shall be identified by grades of commercial Propane, commercial Butane, commercial PB Mixtures or Special-Duty Propane (HD5)[14] Compressed Natural Gas How Compressed Natural Gas is to be Identified: for the purposes of this regulation, it can be identified by the term "Compressed Natural Gas" or "CNG." Retail Sales of Compressed Natural Gas Sold as a Vehicle Fuel. Method of Retail Sale All compressed natural gas kept, offered, or exposed for sale or sold at retail as a vehicle fuel shall be in terms of the gasoline liter equivalent (GLE) or gasoline gallon equivalent (GGE). Retail Dispenser Labeling [14] Identification of Product. Each retail dispenser of compressed natural gas shall be labeled as "Compressed Natural Gas." Conversion Factor. All retail compressed natural gas dispensers shall be labeled with the conversion factor in terms of kilograms or pounds. The label shall be permanently and conspicuously displayed on the face of the dispenser and shall have either the statement "1 Gasoline Liter Equivalent (GLE) is equal to 0.678 kg of Natural Gas" or "1 Gasoline Gallon Equivalent (GGE) is equal to 5.660 lb of Natural Gas" consistent with the method of sale used. Pressure CNG is dispensed into vehicle fuel containers with working pressures of 16 574 kPa, 20 684 kPa, or 24 821 kPa. The dispenser shall be labeled 16 574 kPa, 20 684 kPa, or 24 821 kPa corresponding to the pressure of the CNG dispensed by each fueling hose. Liquefied Natural Gas[14] How Liquefied Natural Gas is to be Identified: For the purposes of this regulation, liquefied natural gas shall be identified by the term "Liquefied Natural Gas" or "LNG."
  3. Section 2. Standard Fuel Specifications Gasoline and Gasoline-Oxygenate Blends :- (as defined in this regulation) shall meet the following requirements :-The most recent version of ASTM D 4814, "Standard Specification for Automotive Spark Ignition Engine Fuel," except that volatility standards for unleaded gasoline blended with ethanol shall not be more restrictive than those adopted under the rules, regulations, and Clean Air Act waivers of the U.S. Environmental Protection Agency (which includes rules promulgated by the State). Gasoline blended with ethanol shall be blended under any of the following three options The base gasoline used in such blends shall meet the requirements of ASTM D 4814,[1] or The base gasoline used in such blends shall meet all the requirements of ASTM D 4814, except distillation, and the blend shall meet the distillation requirements of the ASTM specification. Blends of gasoline and ethanol shall not exceed the ASTM D 4814, vapor pressure standard by more than 1.0 psi. Minimum Antiknock Index (AKI):- The AKI shall not be less than the AKI posted on the product dispenser or as certified on the invoice, bill of lading, shipping paper, or other documentation.[2] Minimum Motor Octane Number :-The minimum motor octane number shall not be less than 82 for gasoline with an AKI of 87 or greater. Minimum Lead Content to Be Termed "Leaded":- Gasoline and gasoline oxygenate blends sold as "leaded" shall contain a minimum of 0.013 gram of lead per liter (0.05 g per U.S. gal).[12] Lead Substitute Gasoline:- Gasoline and gasoline-oxygenate blends sold as "lead substitute" gasoline shall contain a lead substitute which provides protection against exhaust valve seat recession equivalent to at least 0.026 gram of lead per liter (0.10 g per U.S. gal).[4] Documentation of Exhaust Valve Seat Protection :- Upon the request of the director, the lead substitute additive manufacturer shall provide documentation to the director that demonstrates that the treatment level recommended by the additive manufacturer provides protection against exhaust valve seat recession equivalent to or better than 0.026 gram per liter (0.1 g/gal) lead. The director may review the documentation and approve the lead substitute additive before such additive is blended into gasoline. This documentation shall consist of: Test results as published in the Federal Register by the EPA Administrator as required in Section 211(f)(2) of the Clean Air Act;[7] or Until such time as the EPA Administrator develops and publishes a test procedure to determine the additive's effectiveness in reducing valve seat wear, test results and description of the test procedures used in comparing the effectiveness of 0.026 gram per liter lead and the recommended treatment level of the lead substitute additive shall be provided. Blending :- Leaded, lead substitute, and unleaded gasoline-oxygenate blends shall be blended according to the EPA "substantially similar" rule or an EPA waiver for unleaded fuel. Diesel Fuel shall meet the most recent version of ASTM D 975, "Standard Specification for Diesel Fuel Oils." Premium Diesel Fuel :- Effective January 1, 2000, all products identified on retail dispensers, bills of lading, invoices, shipping papers, or other documentation such as premium, super, supreme, plus, or premier must conform to at least two of the following requirements Energy Content :-A minimum energy content of 38.65 MJ/L, gross (138,700 BTU/gallon, gross) as measured by ASTM Standard Test Method D 240. Cetane Number :- A minimum cetane number of 47.0 as determined by ASTM Standard Test Method D 613. Low Temperature Operability:- A cold flow performance measurement which meets the ASTM D 975 tenth percentile minimum ambient air temperature charts and maps by either ASTM Standard Test Method D 2500 (Cloud Point) or ASTM Standard Test Method D 4539 (Low Temperature Flow Test, LTFT). Low temperature operability is only applicable October 1 March 31 of each year.[7] Thermal Stability:- A minimum reflectance measurement of 80 percent using a green filter in the Octel America's Test Method No. F21 61 (180 minutes, 150 °C). Fuel Injector:- Cleanliness A Coordinating Research Council (CRC) rating of 10.0 or less and a flow loss of 6.0 percent or less as determined by the Cummins L 10 Injector Depositing Test. When a fuel uses a detergent additive to meet the requirement, upon the request of the Director, the fuel marketer shall provide test data indicating the additive being used has passed the Cummins L 10 Injector Depositing Test requirements when combined with Caterpillar 1 K (CAT 1 K) reference fuel. The Director may also request records or otherwise audit the amount of additive being used to ensure proper treatment of fuels according to the additive manufacturer's recommended treat rates[8] Upon the request of the Director, the fuel marketer shall provide an official "Certificate of Analysis" of the physical properties of the additive. Upon the request of the Director, the fuel supplier shall provide a sample of detergent additive in an amount sufficient to be tested with CAT 1 K reference fuel in a Cummins L 10 Injector Depositing Test. The regulatory agency requesting the sample shall be responsible for all costs of testing. When a fuel marketer relies on the inherent cleanliness of the diesel fuel to pass the Cummins L 10 Injector Depositing Test or if the fuel requires a lower detergent additive level than the amount required when the additive is used with the CAT 1 K reference fuel, the fuel marketer shall provide, upon the request of the Director, annual test results from an independent laboratory that confirms the fuel meets the requirements of 2.2.1.(e). The time of fuel sampling and testing shall be at the Director’s discretion. The Director may witness the sampling of the fuel and the sealing of the sample container's with security seals. The Director may request confirmation from the testing laboratory that the seals were intact upon receipt by the laboratory. The final test results shall be provided to the Director. All costs for sampling, transporting, and testing shall be the responsibility of the fuel supplier. If the annual test complies, any additional testing at the request of t Director shall be paid for by the regulatory agency. Aviation Turbine Fuels shall meet the most recent version of ASTM D 1655, "Standard Specification for Aviation Turbine Fuels."[1] Aviation Gasoline shall meet the most recent version of ASTM D 910, "Standard Specification for Aviation Gasoline." Fuel Oils shall meet the most recent version of ASTM D 396, "Standard Specification for Fuel Oils." Kerosene (Kerosene) shall meet the most recent version of ASTM D 3699, "Standard Specification for Kerosene." Ethanol intended for blending with gasoline shall meet the most recent version of ASTM D 4806, "Standard Specification for Denatured Fuel Ethanol for Blending with Gasoline for Use as Automotive Spark-Ignition Engine Fuel."[1] Liquefied Petroleum (LP) Gases shall meetASTM D 1835, "Standard Specification for Liquefied Petroleum (LP) Gases." Note: Also reference Gas Processors Association 2140, "Liquefied Petroleum Gas Specification and Test Methods." Compressed Natural Gas (CNG) shall meet the most recent version of SAE J 1616, "Recommended Practice for Compressed Natural Gas Vehicle Fuel." E85 Fuel Ethanol shall meet the most recent version of ASTM D 5798, "Standard Specification for Fuel Ethanol (Ed75-Ed85) for Automotive Spark-Ignition Engines." M85 Fuel Methanol shall meet the most recent version of ASTM D 5797, "Standard Specification for Fuel Methanol M70-M85 for Automotive Spark Ignition Engines."[1]
  4. Kerosene :- It means a refined middle distillate suitable for use as a fuel for heating or illuminating, the classification of which shall be defined by ASTM D 3699.[2] Lead Substitute :- It means an EPA-registered gasoline additive suitable, when added in small amounts to fuel, to reduce or prevent exhaust valve recession (or seat wear) in automotive spark-ignition internal combustion engines designed to operate on leaded fuel. Lead Substitute Engine Fuel :- It means, for labeling purposes, a gasoline or gasoline-oxygenate blend that contains a "lead substitute."[12] Leaded :- It means, for labeling purposes, any gasoline or gasoline-oxygenate blend which contains more than 0.013 gram of lead per liter (0.05 g lead per U.S. gal). NOTE: EPA defines leaded fuel as one which contains more than 0.0013 gram of phosphorus per liter (0.005 g per U.S. gal), or any fuel to which lead or phosphorus is intentionally added. Liquefied Natural Gas (LNG) :-It means natural gas that has been liquefied at -126.1 EC ( 259 EF) and stored in insulated cryogenic tanks for use as an engine fuel.[6] Liquefied Petroleum Gas (LPG) :- It means a mixture of normally gaseous hydrocarbons, predominantly propane, or butane, or both, that has been liquefied by compression or cooling, or both to facilitate storage, transport, and handling.[6] Low Sulfur :- It means low sulfur diesel fuel that meets ASTM D 975 (e.g., Grade Low Sulfur No. 1-D or Grade Low Sulfur No. 2-D) standards. Diesel fuel containing higher amounts of sulfur for off-road use is defined by EPA regulations.[11] Low Temperature Operability :- It means a condition which allows the uninterrupted operation of a diesel engine through the continuous flow of fuel throughout its fuel delivery system at low temperatures. Fuels with adequate low temperature operability characteristics have the ability to avoid wax precipitation and clogging in fuel filters.[11] M100 Fuel Methanol :- It means nominally anhydrous methyl alcohol, generally containing small amounts of additives, suitable for use as a fuel in a compression-ignition internal combustion engine.[10] M85 Fuel Methanol :- It means a blend of methanol and hydrocarbons of which the methanol portion is nominally 70 to 85 volume percent.[10] Motor Octane Number :- It means a numerical indication of a spark-ignition engine fuel's resistance to knock obtained by comparison with reference fuels in a standardized ASTM D 2700 Motor Method engine test.[2] Oxygen Content of Gasoline :- It means the percentage of oxygen by mass contained in a gasoline.[2] Oxygenate :- It means an oxygen-containing, ash less, organic compound, such as an alcohol or ether, which can be used as a fuel or fuel supplement.[2,9] Reformulated Gasoline :- It means a volatile mixture of liquid hydrocarbons and oxygenates meeting the reformulated gasoline requirements of the Clean Air Act Amendments of 1990 and suitable for use as a fuel in a spark-ignition internal combustion engine.[11] Research Octane Number :- It means a numerical indication of a spark-ignition engine fuel's resistance to knock obtained by comparison with reference fuels in a standardized ASTM D 2699 Research Method Engine Test.[2] SAE :- It means the Society of Automotive Engineers, a technical organization for engineers, scientists, technicians, and others in positions that cooperate closely in the engineering, design, manufacture, use, and maintainability of self-propelled vehicles.[8] Substantially Similar :- It means the EPA's "Substantially Similar" rule, Section 211 (f) (1) of the Clean Air Act [42 U.S.C. 7545 (f) (1)].[8] Thermal Stability :- It means the ability of a fuel to resist the thermal stress which is experienced by the fuel when exposed to high temperatures in a fuel delivery system. Such stress can lead to formation of insoluble gums or organic particulates. Insoluble (e.g., gums or organic particulates) can clog fuel filters and contribute to injector deposits.[7] Total Alcohol :- It means the aggregate total in volume percent of all alcohol contained in any fuel.[10] Total Oxygenate :- It means the aggregate total in volume percent of all oxygenates contained in any fuel.[2,9] Unleaded :- In conjunction with "engine fuel" or "gasoline" means any gasoline or gasoline-oxygenate blend to which no lead or phosphorus compounds have been intentionally added and which contains not more than 0.013 gram of lead per liter (0.05 g lead per U.S. gal) and not more than 0.0013 gram of phosphorus per liter (0.005 g phosphorus per U.S. gal).
  5. Petroleum Refinery Engineering quiz 3

    pl try again... there was a permission issue which is resolved now... Sorry for inconvenience
  6. 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 ?
  7. Version

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    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)
  8. 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.
  9. What are the reasons of removal of particles from effluent gas? The main reasons for the removal of particles from effluent gas are: In order to protect and maintain the health of the workers and operators in the plant. It is also done to protect the surrounding population. The primary danger is due to the inhaling of the dust particles which can cause health issues. It is also done to minimize the chances of explosions. Many carbonaceous materials remain suspended in air and when mixed with finely powdered metals can form a highly combustible mixture. Particles are also removed to reduce the loss of valuable materials. It can also be used to recycle the gas for ex in case of blast furnaces the gas is used to fire the stoves.
  10. What are the assumptions made for Kynch Theory? The following assumptions are made for the Kynch Theory: Across the horizontal layer the particle concentration is uniform The effects of the wall can be ignored. No differential settings of particles are considered due to shape, size or composition changes or differences. The velocity at which particles fall depends only on the local concentration of the particles and nothing else. The concentration is considered to be uniform throughout or it can be assumed to increase towards the bottom. The velocity of sedimentation approaches zero as the concentration reaches the limiting value. This limiting value corresponds to the sediment layer at the bottom which gets deposited.
  11. What is carbon sequestration? A technique for capturing carbon dioxide for a long term in order to reduce its effects on global warming.
  12. 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
  13. What is corrosion? Which is the most important material used for metallic coating?
  14. What is use of Reynolds number in designing of Heat exchange?
    @uday it is working fine - pl try again... i just downloaded to check for you
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