Q4. A fluidized bed is used in the production of aniline by the hydrogenation of nitrobenzene. Single-stage cyclones, followed by candle filters, are used to remove fines from the gases leaving the fluidized bed. The reactor operates at a temperature 270°C and a pressure of 2.5 bara. The reactor diameter is 10 m. Hydrogen is used in large excess in the reaction, and for the purposes of this exercise, the properties of the gas may be taken as those of hydrogen at the reactor conditions. The density of the catalyst particles is 1800 kg/m'. The estimated particle size distribution of the fines is: Particle size, um Percentage by weight less than 50 30 20 20 5 5 40 10 100 70 40 10 A 70% recovery of the solids is required in the cyclones. For a gas flow rate of 100,000m/h, at the reactor conditions, determine how many cyclones operating in parallel are needed and design a suitable cyclone? Estimate the size distribution of the particles entering the filters? 22

Fruit juices at 20 ° C containing 5% total solids were concentrated via a single effect evaporator. The evaporator is operated in a vacuum at an evaporation temperature of 80 ° C, and 85% quality steam is supplied at 169.06 kPa. The desired concentration of the final product is 40% total solids. The rate of concentrated product leaving the evaporator is 3000 kg / hour. The specific heat of fruit juice is 4.05 kJ / (kg ° C), and the concentrated product is 3,175 kJ / (kg ° C). Count a. The required steam rate is = Answerkg / hour. b. Steam economy when the condensate temperature is released at 90 ° C. = Answer (kg of water evaporates / kg of steam)

1. Fruit juice at 20 ° C containing 5% total solids concentrated via a single effect evaporator. The evaporator is operated in a vacuum at an evaporation temperature of 80 ° C, and 90% quality steam is supplied at 169.06 kPa. The desired concentration of the final product is 40% total solids. The rate of concentrated product leaving the evaporator is 2500 kg / hour. The specific heat of fruit juice is 4.05 kJ / (kg ° C), and the concentrated product 3.175 kJ / (kg ° C). CountA. The required steam rate is = Answererkg / hour.b. Steam economy if the condensate temperature cannot be released at 90 ° C. = Answer (kg evaporated air / kg steam)

Tomato pulp (40% solids content) is heated by flowing it into a steam injection heater at a rate of 500 kg / hour. 85% quality steam under 180 kPa is supplied to the heater at a rate of 40 kg / hour. If it is assumed that the heat exchanger efficiency is 85% and the initial slurry specific heat is 3.2 kJ / (kg K), the slurry specific heat during the heating process corresponds to the function Cp = Cpw (water fraction) + Cps (solids fraction). a. Determine the temperature of the product leaving the heater when the initial temperature is 35 ° C. =....° C. b. Determine the total solids fraction of the product after heating. = ...%

An open boiler system uses the combustion of kerosene in the air to produce the needed heat. Kerosene can be approximated as C12H26. The reactants and products are at a pressure of 1atm. The temperature of the fuel and air entering the combustion chamber is 298K and the temperature of the products is 400K. The fuel is burned at stoichiometric conditions. Calculate the heat released per kmole of fuel for the combustion of kerosene in this system with the given inlet and outlet conditions for complete combustion (only H2O, CO2, and N2 in products).