Calorimeters schematic

Figure 11.13 Internal energy changes for paths at constant volume in a bomb calorimeter (schematic). R denotes reactants and P denotes products.

Figure Bl.27.2. Schematic vertical section of a high-temperature adiabatic calorimeter and associated thennostat (Reprinted with penuission from 1968 Experimental Thermodynamics vol I (Butterworth).)...

Figure Bl.27.7. Schematic diagram of isothennal displacement calorimeter A, glass calorimeter cell B, sealed heater C, stainless steel stirrer D, thennistor E, inlet tube F, valve G, window shutters Ft, silver rod ...

Figure Bl.27.11. Schematic diagram of a Tian-Calvet heat-flux or heat-conduction calorimeter.

Figure Bl.27.12. Schematic diagram of an accelerating rate calorimeter (ARC).

The SIMULAR, developed by Hazard Evaluation Laboratory Ltd., is a chemical reactor control and data acquisition system. It can also perform calorimetry measurements and be employed to investigate chemical reaction and unit operations such as mixing, blending, crystallization, and distillation. Ligure 12-24 shows a schematic detail of the SIMULAR, and Ligure 12-25 illustrates the SIMULAR reaction calorimeter with computer controlled solids addition. 

The heat of combustion of solids or liquids is usually measured in a device known as an oxygen bomb calorimeter. Such a device operates at a constant volume between states 1 and 2, and its heat loss is measured by means of the temperature rise to a surrounding water-bath. This is schematically shown in Figure 2.2. The combustion volume is charged with oxygen and a special fuel is added to ensure complete combustion of the fuel to be measured. Since the process is at constant volume (V), we have... 

Figure 10.5 Schematic representation of the stepwise heating mode of operation of an adiabatic calorimeter.

The Contalab, initially supplied by Contraves, was purchased by Mettler-Toledo, which is now placing less emphasis on this design than on the RC1. Some comments here are appropriate, however, since it is another type of bench-scale calorimeter, and units continue to be used. Its measuring system is based on the heat balance principle, in which a heat balance is applied over the cooling/heating medium. For this purpose, both the flow rate of the coolant and its inlet and outlet temperatures must be known accurately. Figure 3.12 is a schematic plan of the Contalab. 

Figure 3.6 Schematic representation of the bomb calorimeter for measuring the changes in internal energy that occur during combustion. The whole apparatus approximates to an adiabatic chamber, so we enclose it within a vacuum jacket (like a Dewar flask)...

Figure 6.2 Schematic representation of (a) an adiabatic calorimeter, (b) an isoperibol calorimeter, and (c) a heat conduction (or heat flow) calorimeter. fc and 7] are the temperatures of the calorimeter proper and the external jacket, respectively, and is the heat flow rate between the calorimeter proper and the external jacket.

Figure 9.2 A schematic diagram of a Calvet s calorimeter, adapted from [157], Only one of the twin calorimetric units (A), with its thermopiles (T) is shown. These units fit into high-conductivity metal blocks (B). Care cones for equipartition of thermal fluctuations D is a thick metal cylinder surrounded by a series of canisters (E). H is an electric heater, and the outer cylinder (I) is a thermal insulator.

Figure 5. Schematic of flow, heat-capacity calorimeter...

This highly sensitive calorimeter needs to be connected to a sensitive volumetric system in order to determine accurately the amounts of gas or vapor adsorbed. A schematic representation of the whole assembly is shown in Figure 13.4 [147]. The volumetric determination of the adsorbed amount of gas is performed in a constant-volume vessel linked to a vacuum pump. The apparatus consists of two parts the measuring section equipped with a capacitance manometer, and the vessels section that includes the cells placed in the calorimeter (a sample cell in which the adsorbent solid is set, and an empty reference cell). 

Fig. 1. Schematic representation of the time resolved photoacoustic calorimeter. Solid lines indicate light path heavy solid lines represent signal paths. (After Peters and Snyder)...

The amount of heat transferred during a reaction can be measured with a device called a calorimeter, shown schematically in Figure 8.8. At its simplest, a calorimeter is just an insulated vessel with a stirrer, a thermometer, and a loose-fitting lid to keep the contents at atmospheric pressure. The reaction is carried out inside the vessel, and the heat evolved or absorbed is calculated from the temperature change. Because the pressure inside the calorimeter is constant (atmospheric pressure), the temperature measurement makes it possible to calculate the enthalpy change AH during a reaction. 

FIGURE 6.5 Schematic of Tian-Calvet calorimeter at the Canadian National Research Council. (Reproduced from Handa, Y.P., Calorimetric Studies of Laboratory Synthesized and Naturally Occurring Gas Hydrates, paper presented at AIChE 1986 Annual Meeting Miami Beach, November 2-7, 28 (1986b). With permission.)... 

In the CSM laboratory, Rueff et al. (1988) used a Perkin-Elmer differential scanning calorimeter (DSC-2), with sample containers modified for high pressure, to obtain methane hydrate heat capacity (245-259 K) and heat of dissociation (285 K), which were accurate to within 20%. Rueff (1985) was able to analyze his data to account for the portion of the sample that was ice, in an extension of work done earlier (Rueff and Sloan, 1985) to measure the thermal properties of hydrates in sediments. At Rice University, Lievois (1987) developed a twin-cell heat flux calorimeter and made AH measurements at 278.15 and 283.15 K to within 2.6%. More recently, at CSM a method was developed using the Setaram high pressure (heat-flux) micro-DSC VII (Gupta, 2007) to determine the heat capacity and heats of dissociation of methane hydrate at 277-283 K and at pressures of 5-20 MPa to within 2%. See Section 6.3.2 for gas hydrate heat capacity and heats of dissociation data. Figure 6.6 shows a schematic of the heat flux DSC system. In heat flux DSC, the heat flow necessary to achieve a zero temperature difference between the reference and sample cells is measured through the thermocouples linked to each of the cells. For more details on the principles of calorimetry the reader is referred to Hohne et al. (2003) and Brown (1998). 

Figure 9.3 Schematic drawing of calorimeters for measuring heats of adsorption under constant volume and constant pressure conditions. The active volume is filled with the adsorbent usually...

Figure 14. Integrated Scanning Pyroelectric Microcalorimeters a. schematic drawing of the integrated scanning pyroelectric microcalorimeter b. photograph of an assemble integrated scanning pyroelectric calorimeter on its ceramic mount.

Figure 18.11. Schematic of (A) a differential thermal analyzer and (B) differential scanning calorimeter for a TA Instruments, Inc.-type configuration. Modified from Richardson (1989). Reproduced by permission of Elsevier, Ltd.

Figure 1. Schematic diagrams of sections through adiabatic-type calorimeters. A Adiabatic shield calorimeter. B Semiadiabatic calorimeter, a, calorimetric vessel b, air or vacuum c, thermostatted bath d, thermometer e, stirrer f, calibration heater g, adiabatic shield.

Figure 3. Schematic diagram of a section through a thermopile heat conduction calorimeter, a, calorimetric vessel b, heat sink c, thermopile d, stirrer e, calibration heater f, air.

Figure 6. Schematic diagrams of sections through two types of twin calorimeters. A Twin heat conduction (micro)calorimeter (vessels not shown). B Semiadiabatic twin calorimeter, a, vessel holder b, thermopile c, heat sink d, vessel (stirrer, thermometer, heater not shown) e, air or vacuum.

Figure 14. Schematic picture of a whole body calorimeter with its ventilatory system, a, Fan b, steam c, saturator d, heater e, respiratory heater f, condenser g, respiratory condenser h, gradient layer. Adapted from J6quier et al. (1975).

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