Groundwater contaminated with 1,1,1-trichloroethane (TCA) is to be air-stripped at 25°C and 1.1 bar pressure at a rate of 9000 kg/h. The feed water has 600 ppm of the VOC. A stripping column of suitable diameter with eight trays having 40% overall efficiency is available. The exit stripping air must not contain more than 2.5% TCA by volume. The equilibrium relation is y = 950 x. Calculate the percentage removal of TCA achievable in the column.

Fruit juices at 25 °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 3.175 kJ / (kg °C). Count : a. The required steam rate is = Answer kg / hour. b. Steam economy if the condensate temperature cannot be released at 90 °C. = Answer (kg evaporated air / kg vapor)

A single effect evaporator was used to concentrate 8000 kg / hr of tomato juice from 5% total solids to 30% total solids. The juice enters the evaporator at 15 ° Celsius. The evaporator was operated by steam (80% quality) at 143.27 kPa. The vacuum in the evaporator allows the juice to boil at 80 ° Celsius. the specific heat of the Ecer material is 4.1 KJ / (kg degrees Celsius) and the concentrate product is 3.1 KJ / (kg degrees Celsius). Count it a. Steam demand rate = b. Steam economy if Condensate temperature is released at 75 ° Celsius =

A fully charged battery contains 0.02 kmol Ag₂O (silver oxide) and 0.02 kmol Zn (zinc). The battery is initially at a temperature of 21°C. The fully charged battery is then discharged for half an hour under adiabatic conditions (no heat leaves the system). During the half hour of being discharged, the electric current from the battery does 200 kJ of work external to the battery system (none of this external work heats the battery). During this half hour, 0.001 kmol of both reactants are consumed in the net cell discharge reaction: Please see the following table for heat capacities and heats of formation. The heats of formation below show the amount of energy (kJ) needed to form one kmole of each component. If the heat of formation is negative, then forming that species releases energy (to do work or provide heat). Therefore, to create one kmole of silver oxide 29000 kJ energy is released and is generated in the battery (for work or heat), and if one kmole of silver oxide decomposes…

A single effect evaporator was used to concentrate 8000 kg / hr of tomato juice from 5% total solids to 30% total solids. The juice enters the Evaporator at 20 ° C. The evaporator is operated on Steam (85% quality) at 143.27 kPa. The vacuum in the evaporator allows the juice to boil at 80 ° C. The specific heat of the dilute material is 4.1 kJ / (kg ° C) and the concentrate product is 3.1 kJ / (kg ° C). Count it (a) Steam demand rate = Answerkg / hour. b. Steam economy when condensate temperature is released at 75 ° C. = Answer(kg of water evaporated / kg of steam)

A single effect evaporator is used to concentrate 10 000 kg / hr of tomato juice from 5% total solids to 30% total solids. The juice enters the Evaporator at 20 ° C. The evaporator is operated on Steam (80% quality) at 143.27 kPa. The vacuum in the evaporator allows the juice to boil at 80 ° C. The specific heat of the dilute material is 4.1 kJ / (kg ° C) and the concentrate product is 3.1 kJ / (kg ° C). Count it (a) Steam demand rate = Answer kg / hour. b. Steam economy when condensate temperature is released at 75 ° C. = Answer (kg of water evaporated / kg of steam)

Q3(a) A stream of benzene vapor at 580 °C and 1 atm is cooled and converted to a liquid at 25 °C and latm in a continuous condenser. (i) (ii) Illustrate a completely process path for the above process. Calculate the total enthalpy change for this process.

8.29 Show complete solution and diagram

A continuous single-effect evaporator is to be fed with 5000 kg/hr of solution containing 1 wt% solute, the feed is at a temperature of 303 K. it is to be concentrated to a solution of 2 wt% solute. The evaporation is at atmospheric pressure (101.3 kPa) and the area of the evaporator is 69.7 m2 Saturated steam is supplied at 143.3 kPa for heating. It is assumed that the Cp of feed is the same with that of water which is 4.1 kj/kg-K. Assume no BPR. Calculate: overall heat transfer coefficient

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. = ...%