Molar steam flow rate

The steam/carbon ratio S/C, which is the ratio of molar steam flow rate to the molar flow rate of the fuel multiplied by the number of carbon atoms in the fuel, x ... 

Heavy naphta molar flow rate 8 N703 reboiler steam flow rate... 

The molar ratio of steam to ethylbenzene at the inlet is 9 1. The bed is 1 m in length and the void fraction is 0.5. The inlet pressure is set at 1 atm and the outlet pressure is adjusted to give a superficial velocity of 9 m/s at the tube inlet. (The real design problem would specify the downstream pressure and the mass flow rate.) The particle Reynolds number is 100 based on the inlet conditions 4 x 10 Pa s). Find the conversion, pressure, and velocity at the tube outlet, assuming isothermal operation. 

The inlet methanol molar concentration was determined by the mass of catalyst, S/C ratio, and W/F ratio. Here, steam-to-carbon (S/C) ratio is defined as the ratio of steam molecules per carbon atom in the reactant feed and W/F ratio as the amount of catalyst loading into the channel divided by the amount of methanol molar flow rate. For more information on the design parameters, physical properties, and operating conditions, refer to Jung et al. [12]. 

In the model cell shown in Figure 4.1, steam of molar flow rate, fc and pressure, Pc, is reduced to hydrogen gas of flow rate,/D — f, and partial pressure, P0(f0 — f)/f0, in the cathode compartment (fa /)//D is a conversion ratio from steam (F420) to F42 (steam conversion ratio). The partial pressure of 02, is assumed to be unity. Using the steam conversion ratio, X = (fa f )/f0, Equation 4.4 can be written as follows ... 

This last item is important because it leads to an easy way to accommodate the molar contraction of the gas as the reaction proceeds. The program calculates steady-state profiles of each of these down the length of the tubular reactor, given the reaction kinetics models, a description of the reactor and catalyst geometries, and suitable inlet gas flow-rate, pressure and composition information. Reactor performance is calculated from the flow-rate and composition data at the reactor outlet. Other data, such as the calculated pressure drop across the reactor and the heat of reaction recovered as steam, are used in economic calculations. The methods of Dixon and Cresswell (7) are recommended for heat-transfer calculations. 

The reactions are elementary and take place in the gas phase. The reaction is to be carried out isothermally and as a first approximating pressure drop will be neglected. The feed consists of hydrogen gas, carbon monoxide, j carbon dioxide, and steam. The total molar flow rate is 300 mo /s. The entering pressure may be varied between 1 atm and 160 atm and the entering temperature between 300 K and 400 K. Tubular (PFR) reactor volumes between 0.1 m and 2 m are available for use. 

J. Snyder and B. Subramaniam, Chem. Eng. Sci., 49, 5585 (1994)]. Ethylbenzene is fed at(a rate of 0.00344 kmol/s to a 10.0-m PFR reactor along with inert steam at (a total pressure of 2.4 atm. The steam/ethylbenzene molar ratio is initially [i.e., parts (a) to (c)] 14.5 1 but can be varied. Given the following data, find the exiting molar flow rates of styrene, benzene, and toluene for the following inlet temperatures when the reactor is operated adiabatically. 

Steam reforming (SR), partial oxidation (POX), and ATR are three major commercial reforming processes. In this work, ATR syngas was chosen as the feed gas, and the feed inlet molar flow rate, nt0, was 1 mol/s. With the composition given in Table 9.1, this flow rate was chosen because a sufficient H2 molar flow rate would hence be provided to generate a power of 50 kW via the fuel cell for a five-passenger car.4 Heated air was used as the sweep gas. 

Yee et al. (2003) make use of the original NSGA (Srinivas and Deb, 1994) to optimize both adiabatic and steam-injected styrene reactors. A pseudo-homogeneous model was used to describe the reactor. This study maximizes three objectives the amount of styrene produced, the selectivity of styrene and the yield of styrene. Two- and three-objective optimization problems are studied using combinations from these objectives. The decision variables for the adiabatic configuration are the feed temperature of ethyl benzene, inlet pressure, molar ratio of steam to ethyl benzene and the feed flow rate of ethyl benzene. The problem considers three constraints related to temperatures which are handled... 

Steam stripping is to be used to remove a solvent from contaminated soil. An enriching colunm will be used to recover the solvent from the stream. A vapor feed of 40 mol/hr with a composition of 20 mol% solvent and 80 mol% water enters an enriching column. The distillate stream is to have a flow rate of 5 mol/hr and a concentration of 90 mol% solvent. The internal reflux ratio is 0.875 and constant molar overflow (CMO) may be assumed. Graph the operating line to predict the number of equilibrium stages in this enriching column. 

Dv = the molar flow rate of two-phase (or volatile) components in the distillate Ds = molar flow rate of steam in the distillate at any time t. 

This equation is derived in a manner similar to (12.128) h is the height of a transfer unit, h dx/dz replaces dx/di, and G, the molar flow rate of steam, plays the role of the tails flow rate N. 

F molar flow rate of supplementary feed to hot tower g ratio of steam rate to minimum rate G vapor molar flow rate h hei t of transfer unit H moles of hydrogen... 

Two streams 1 and 2 are being mixed in a well-stirred tank, producing a product stream 3 (Figure 4.8). Each of the two feed streams is composed of two components, A and B, with molar concentrations cA, cb, and ca2, cb2, respectively. Also let F, and F2 be the volumetric flow rates of the two streams (ft3/min, m3/min) and T i and T2 their corresponding temperatures. Finally, let cA, c b3, F3, and T3 be the concentrations, flow rate, and temperature of the product stream. A coil is also immersed in the liquid of the tank and it is used to supply heat to the system with steam, or remove heat with cooling water. 

At the base of the distillation column, a liquid product stream (the bottoms product) is removed with a flow rate FB and a composition xB (molar fraction of A). A liquid stream with a molar flow rate V is also drawn from the bottom of the column and after it has been heated with steam, it returns to the base of the column. The composition of the recirculating back to column stream is xB. Let MB be the liquid holdup at the base of the column. 

Figure 4. Effect of Sweep-To-Feed Molar Flow Rate Ratio on Hydrogen Recovery for the Countercurrent Membrane Reactor With the 18.63% CO Syngas From Steam Reforming...

Catalytic testing was performed for steam reforming of methane in a tubular fixed-bed quartz reactor, at atmospheric pressure, in the temperature range Tr=600-800°C, using 0.2g of catalyst and molar ratios of CH4/H20=1 1 and 1 3 at a total flow rate of 50ml/mn. The catalyst was reduced in situ at 800°C in a flow of 5ml/mn of pure Ha- The products and reactants were analyzed by GC. The conversion and yields are calculated as described in a previous study [10]. 

This reaction is carried out in the presence of a diluent, steam. The diluent ratio is K (moles diluent/moles hydrocarbon). Furthermore, 1 mole of propane leads to 2 moles of products, in other words the molar expansion 5 — 1. The relation between the propane concentration and the conversion has to account for the dilution and expansion and is obtained as follows. For a feed of moles of propane per second, the flow rates in the reactor at a certain distance where a... 

Flow controllers are installed on the steam to the base of the two columns. These flow rates are ratioed to the feed flows to the respective column by using multipliers. The molar steam-to-feed ratio in the preflash column is 125.9/2722 = 0.04625. The total crude feed is used (after the summer). The molar steam-to-feed ratio in the pipestiU is 302.1/1654 = 0.1827. 

A hot exhaust gas is heating a boiler to produce superheated steam at 100 psia and 400 °F. In the meantime, the exhaust gas is cooled from 2500 °F to 350 °F. Saturated liquid water (stream 1) at 14.7 psia enters the boiler with a flow rate of 200 Ib/h. Superheated steam (stream 2) is used in a turbine, and discharged as saturated steam (stream 3) at 14.7 psia. Determine (a) The molar flow rate of the exhaust gas needed (b) The lost work in each unit. 

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