Cooling-step

Steps. Thermal-swing cycles have at least two steps, adsorption and heating. A cooling step is also normally used after the heating step. A portion of the feed or product stream can be utilized for heating, or an independent fluid can be used. Easily condensable contaminants may be regenerated with noncondensable gases and recovered by condensation. Water-iminiscible solvents are stripped with steam, which may be condensed and separated from the solvent by decantation. Fuel and/or air may be used when the impurities are to be burned or incinerated. 

Recovery Process. The process for making sodium sulfate [7757-82-6] is different at each faciUty extracting it from brine. One step common to all facihties is a cooling step to form Glauber s salt followed by a purification and recrystallization step to form anhydrous sodium sulfate. 

Note that during the cooling step the maximum amount of evaporation which is permitted by the material balance is 50 lb for the step shown. In an evaporative-cooling step, however, the actual evaporation which results from adiabatic cooling is more than this. Therefore, water must be added back to prevent the NaCl concentration from rising too high otherwise, coprecipitation of NaCl will occur. 

The nomenclature introduced by Hawthorne and Davis [4] is adopted and gas turbine cycles are referred to as follows CHT, CBT, CHTX, CBTX, where C denotes compressor H, air heater B, burner (combustion) T, turbine X, heat exchanger. R and I indicate reversible and irreversible. The subscripts U and C refer to uncooled and cooled turbines in a cycle, and subscripts 1,2, M indicate the number of cooling steps (one, two or multi-step cooling). Thus, for example, [CHT] C2 indicates an irreversible cooled simple cycle with two steps of turbine cooling. The subscript T is also used to indicate that the cooling air has been throttled from the compressor delivery pres.sure. 

For the various reversible cycles described in Section 4.2.1, the thermal efficiency was the same, independent of the number of cooling. steps. This is not the case for the irreversible cycles described in this section. Both the thermal efficiency and the turbine exit temperature depend on the number and nature of cooling steps (whether the cooling air is throttled or not). 

The three phases of the run can be seen clearly the heating step corresponds to the sharp rise on the left-hand side, the data collection step corresponds to the flat part of the curve, and the cooling step is seen as the final part of the curve. 

The net heat input, allowing for outflow of heat in the cooling step and influx ot heat in the expansion, is q = +1.46 k). 

Both the temperature reduction tasks and the reconfiguration of interfacial composition task are not fundamentally required. The temperature reduction is required since the pasteurization tasks leave the product at too high a temperature. The interfacial reconfiguration is required since the interfacial configuration after the cooling step is not the desired one. 

In the heating and cooling steps, the structure of the product does not really lead to a different behavior compared to a homogeneous liquid. So when the relevant physical properties are known (viscosity, heat capacity, thermal conductivity,... 

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