Volumetric heater

The volumetric capacity is adjustable to provide uniform heat transfer to the oil passing through. Heaters are flexible in operation down to about 50 per cent of their designed temperature rise, when the quantity of oil passing through is approximately double. Where the temperature level required with a reduced throughput is outside this range, the heater manufacturer should be consulted. 

Apparatus a. Temp-block module heater, Lab-Line Instruments, Inc., or equivalent. b. Sand for 1. a. c. Conical centrifuge tube with stoppers, 15 mL. d. Volumetric flasks, 10 mL and 200 mL. e. Syringe, 250 /xL. 

A fuel gas consisting of 93 mole percent methane and 7 mole percent nitrogen is burned with 30 percent excess air in a continuous water heater. Both fuel gas and air enter dry at 25°C and atmospheric pressure. Water is heated at a rate of 75(lbm)(s) 1 [34.0kgs-1] from 59(°F) [15°C] to 185(°F) [85°C]. The flue gases leave the heater at 392(°F) [200°C]. Of the entering methane, two-thiids bums to carbon dioxide and one-third bums to carbon monoxide. What volumetric flow rate of fuel gas is required if there are no heat losses to the surroundings ... 

Weigh accurately about 200 mg of a dned, extracted wood meal (40-60 mesh) with known moisture and extractives contents or 50 mg of a dned, purified lignin preparation The specimen, 7ml of 2M NaOH, and 0 4ml of freshly distilled nitrobenzene are placed m a 10-ml stainless steel bomb (Note 1) The bomb is sealed tightly with a screw cap fitted with a Teflon gasket and heated at 170°C for 2 5h m an electrically preheated (170°C), thermostated aluminum block with six holes to accommodate the cylindrically shaped bombs or in a thermostated oil bath The bomb is shaken occasionally and, after the heating period, is removed from the heater and cooled with ice water The oxidation mixture is transferred to a liquid-liquid extractor, and extracted continuously with CHCI, for 4h to remove nitrobenzene reduction products and any excess nitrobenzene The oxidation mixture is acidified to pH 3-4 with cone HC1, and further extracted continuously with CHCI, for 48 h The solvent from the second CHCI, solution is removed at 40°C under reduced pressure to obtain the nitrobenzene oxidation mixture The mixture is then dissolved m 5 ml of CH2C12 and transferred to a 10-ml volumetric flask The solution is made up to 10 ml... 

Fs = volumetric feed flowrate at steady state Ti = feed temperature T = heater temperature Tc = heating coil temperature U = heat transfer coefficient A = heat exchange area p = density of liquid in heater Cp = specific heat of liquid in heater. 

A hot-air dryer is used to reduce the moisture content of 1500 kg/min of wet wood pulp from 0.75 kg H20/kg dry pulp to 0.15 wt% H2O. Air is drawn from the atmosphere at 28°C, 760 mm Hg, and 50% relative humidity, sent through a blower-heater, and then fed to the dryer. The air leaves the dryer at 80 C and 10 mm Hg (gauge). A sample of the exit air is drawn into a chamber containing a mirror and cooled slowly, keeping the gauge pressure at 10 mm Hg. A mist is observed to form on the mirror at a temperature of 40.0 C. Calculate the mass of water removed from the pulp (kg/min) and the volumetric flow rate of air entering the system (m /min). 

The concept of time of flight has also been adopted, similarly to its use in ultrasonic flowmeters for macroscale flows. A heat pulse is generated upstream by a laser or electric coil, and the heated fluid is detected downstream. The time difference is used to determine the velocity and then the volumetric flow rate. However, diffusion of heat in the fluid results in a broadened temperature distribution when the fluid reaches the sensors and hence results in difficulty in determining the transit time accurately. An ion generator can be used to replace the heater for the purpose of determination of the time of flight [6]. 

This work focuses on the kinetic study of the methane catalytic combustion in a honeycomb monolith wash-coated with Pd/y-AhOa (homemade). The experimental conditions were chosen to adequately represent the operation of a domestic-scale catalytic heater, i.e. relatively high volumetric flowrates and high methane molar fractions (Lopez et al., 2000). From experimental data (obtained at conditions of negligible mass transfer resistances) and using a mathematical model for the laboratory reactor, the intrinsic kinetic parameters are calculated for a power law type rate expression. 

This is an exceptionally large mass of metal to be heated in a small degreaser, but the value was chosen to make a point. The point is that not only is there a volumetric size limitation on parts which can dimensionally fit into a vapor degreaser, but there is a mass limit as well, which can require the boilup heater to have an exceptionally large capacity... 

The water heater as shown in Figure 5.63 is a well-mixed, constant-volume (Vi) tank through which fluid flows at a constant mass flow rate w (or p/E whereas F is the volumetric flow rate and p/ is the liquid density) the specific heat capacity of the fluid is C /. Because the incoming fluid temperature Tf is subject to fluctuations, an electric coil to which a simple proportional con-... 

A thermopneumatic valve typically consists of a move-able valve diaphragm, a valve seat, and a resistive heater in a sealed cavity. While electrical power is applied to the resistive heater, the initial volume of gas in the sealed chamber expands. Using the volumetric change of the heated gas in the cavity, the diaphragm structure... 

An oil is to be heated in horizontal multipass heater by steam at 4.4 atmospheres. The steel tubes have inside and outside diameters of 0.016 and 0.019 m with a nraximum length of 4.57 m. The oil enters at 0.91 m/sec with a volumetric flow rate of 150 gallons/min and a temperature of 37.8°C. If the oil is completely mixed after each pass, how many passes are needed to reach to exit temperature of 82.2°C ... 

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