A 25 wt% solution of coffee in water at 70oF is spray-dried to a moisture content of 5% (dry basis) with air entering at 450oF and 1 atm with a humidity of 0.01 lb/lb (dry basis) and exiting at 200oF. Assuming the specific heat of coffee=0.3 Btu/lb-oF, calculate: (a) air rate in lb dry air/lb coffee solution; (b) temperature of evaporation; (c) heat-transfer rate in Btu/lb coffee solution

Seven thousand lb/h of wet, pulverized clay particles with 27% moisture (dry basis) at 15oC and 1 atm enter a flash dryer, where they are dried to a moisture content of 5% (dry basis) with a cocurrent flow of air that enters at 525oC. The dried solids exit at the air wet-bulb temperature of 50oC, while the air exits at 75oC. Assuming the specific heat of clay=0.3 Btu/lb-oF, calculate: (a) flow rate of air in lb/h (dry basis); (b) rate of evaporation of moisture; (c) heattransfer rate in Btu/h.

A filter cake of Calcium Carbonate contained in a tray is to be dried by cross-circulation from the top surface. Each tray is 2.5 cm high with an area of 1.5 m² and is completely filled with 73 kg of wet filter cake having a water content of 30% on dry basis, The heating medium is air at 1 atm and 170°F with a humidity of 0.026 (kg H,O/kg dry air). The average velocity of the air passing across the wet solid is 4 m/sec. Estimate the time in hours to reach the experimentally determined critical moisture content of 10% on the dry basis, if the preheat period is neglected. Assume latent heat of evaporation of water 2500 kJ/kg.

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.

Use the thermo table then calculate.

The result of air temperature measurement obtained dry ball temperature 37°C and wet ball temperature 27.5 °C. Using a graph of psychotry, determine the properties of the air as follows:a. RH : %B. Moisture content : kg of water / kg of airc. Specific volume : m3/kgd. Enthalpi : kJ/kgE. Condensation temperature : °CIf the air is within 162 m3 of space, specify theF. Weight of air (dry air and moisture) : Kgg. amount of water content in the room: kg

A rectifying column consists of a tube arranged vertically and supplied at the bottom with a mixture of benzene and toluene as vapor. At the top, a condenser returns some of the product as a reflux which flows in a thin film down the inner wall of the tube. At one point in the column, the vapor contains 60 mol% benzene and the adjacent liquid reflux contains 51 mol% benzene. The temperature at this point is 92°C. Assuming the diffusional resistance to vapor transfer to be equivalent to the diffusional resistance of a štagnant vapor layer 0.5 mm thick, calculate the rate of interchange of benzene and toluene between vapor and liquid. The molar latent heats of the two materials can be taken as equal. The vapour pressure of toluene at 92°C is 44.0 kN/m2 and the diffusivity of the vapors is 0.053 cm?/s.

A saturated solution containing 150 kilograms of sodium sulfate (mol. wt. = 142) in 600 kilograms of water is fed to Swenson-Walker crystallizer. The solubility of sodium sulfate at 10 °C is 9 kilogram of anhydrous salt per 100 kilogram of water, and the deposited crystals consist of the decahydrate (mol. Wt. = 322). Crystallization is by cooling at 10 °C. If 2% of the water was lost by evaporation during the cooling process, the percent (%) yield in the crystallizer is Blank 1%. **(Express your answer to two (2) decimal places. Do not put units on your answer)**