35501. If a1 and a2 are the relative volatilities when the pressure in the distillation column is 1 and 2 atm respectively. Pick out the correct statement.
35502. The dimension of diffusivity is same as that of the
35503. The temperature to which a vapour gas mixture must be cooled (at varying humidity) to become saturated is called the __________ temperature.
35504. Entrainer used in azeotropic distillation should
35505. In case of steam distillation, the steam leaving the liquid is not completely saturated with distillate vapour, because
35506. Periodic maintenance or preventive maintenance helps to
35507. Leaching of coffee from coffee beans is done by
35508. For contacting a highly soluble gas with a liquid
35509. During drying operation, it is easier to remove the __________ moisture.
35510. With increase in solvent rate, the number of transfer units, NtoG, for a fixed degree of absorption from a fixed amount of gas
35511. Ion exchange process is similar to
35512. A distillation column with N plates is being operated under normal conditions. At some point of time, the operation is shifted to total reflux condition (i.e., no product and residue are being withdrawn and feed to the column is stopped). At the new steady state,
35513. Dryer widely used in a textile industry is __________ dryer.
35514. Hand brakes are applied on
35515. Air at a particular humidity is heated in a furnace. The new dew point
35516. In a packed tower, the value of HETP equals HTUOG, when the equilibrium and the operating lines are (where, HETP = height equivalant to a theoretical plate HTUOG = overall gas phase height of a transfer unit)
35517. The vapour pressure exerted by the moisture contained in a wet solid depends upon the
35518. Smoke is an example of
35519. Which of the following adsorbant is used in the refinning of sugar ?
35520. Stacked packing compared to dumped packing
35521. In McCabe-Thiele method of theoretical plate calculation for a distillation column, the operating lines of stripping and rectifying sections coincide with the diagonal at __________ reflux.
35522. Which of the following parameters remains constant during chemical dehumidifica-tion?
35523. Drying of a solid involves __________ transfer.
35524. Mechanism of moisture removal in case of freeze drying of food stuff is by
35525. The dew point of an unsaturated gas-vapor mixture does not depend upon the __________ of the mixture.
35526. Which is not concerned directly with mass transfer ?
35527. Removal of __________ exemplifies an adsorption unit operation.
35528. Can the efficiency of a plate in the distillation tower be greater than 100% ?
35529. With increase in the mass velocity of the gas, the rate of drying during the constant rate period __________ , if the conduction and radiation through the solid are negligible.
35530. For gas absorption, low viscosity solvents are preferred, because of their
35531. To remove all the moisture from a wet solid it requires exposure to __________ air.
35532. The operating cost of a distillation column at minimum reflux ratio is
35533. The reflux to a distillation column is 100 moles/hr, when the overhead product rate is 50 moles/hr. The reflux ratio is
35534. Molecular diffusivity of a liquid
35535. The wet and 'dry bulb temperature for a vapour-gas mixture are 25°C and 30°C respectively. If the mixture is heated to 45°C at constant pressure, the wet bulb temperature will be __________ °C.
35536. Henry's law states that the
35537. Ammonia present in the coke oven gas is removed by washing with
35538. With increase in temperature, the leaching rate increases due to
35539. Which of the following processes is not an example of adsorption applied to gaseous separations ?
35540. The critical moisture content in case of drying indicates the __________ rate period.
35541. The diameter of a piston is three inches,in metric system the diameter is
35542. According to Poiseuille's law, the permeability for gas flow through a capillary is proportional to (where, μ = gas viscosity)
35543. For a binary mixture distillation process, the degree of freedom is 2. However, if the pressure is fixed in this process, the number of independent variables in this process will be
35544. H2S is being absorbed in a gas absorber unit. The height of the transfer unit based on the overall mass transfer coefficient on the gas side is 0.4 m. The equilibrium data is given by, y = 1.5 x. The bulk concentration of H2S has to be reduced from 0.05 to 0.001 mole fraction in the gas side. The height of the tower (in metres) corresponding to an operating line given by, y = 5x + 0.001 is
35545. Packed column distillation is limited to the column __________ metres.
35546. For the flow of gases through a capillary, with increase in temperature, the permeability __________ as per Knudsen law.
35547. Which of the following is directly concerned with psychrometry ?
35548. Plate efficiency in a distillation column is reduced due to the __________ of liquid.
35549. The most efficient cooling tower out of the following is
35550. Sodium bicarbonate is produced during soda ash manufacture using a __________ tower.