*2.5. Step 5: Evaluation of the Heat Pump Suitability to Di*ff*erent Process GCC Profiles*

The heat duties, inlet and outlet temperatures of the heat source and sink vary among different processes. Pinch Analysis with HP placement is used, performing Steps 1–4 for a set of GCC profiles representing processes with different thermal properties. The T–H diagrams of different processes are shown in Figure 4. The configurations shown represent pairs of process heat sinks and sources of a gradual, steep and medium slope. Combinations of these are possible, but the three configurations in Figure 4 are the basic ones, which help to understand the major trends.

Each of these types of profiles implies a different degree of compatibility with the HP types considered in this work. The compatibility can be qualitatively assessed on the temperature–entropy (T–S) diagrams combining the process heat source/sink profiles with the HP profiles. Such plots are shown in Figure 5. The solid red lines represent the heat release or condensation of the working fluid in the HP, and the solid blue lines are the heat absorption or evaporation of the working fluid. The red dashed lines represent the heat release of the source, and the blue dashed lines represent the heat absorption of the sink. The performance of these three types of HPs (JCHP/VCHP/TCHP) is calculated by varying the inlet and the outlet temperatures of the process heat source and sink, and relating the results to the possible representations of temperature lifts ΔTin, ΔTout, or ΔT1, ΔT2 (e.g., Equations (3)–(6)).

$$
\Delta T\_{\rm in} = T\_{\rm sink-in} - T\_{\rm source-in} \tag{3}
$$

$$
\Delta T\_{out} = T\_{sink-out} - T\_{source-out} \tag{4}
$$

$$
\Delta T\_1 = T\_{sink-in} - T\_{source-out} \tag{5}
$$

$$
\Delta T\_2 = T\_{sink-out} - T\_{source-in} \tag{6}
$$

where: Δ*T*in—The inlet temperature difference of the source and sink, ◦C; Δ*Tout*—The outlet temperature difference of the source and sink, ◦C; Δ*T*1—The difference between the inlet temperature of the sink and the outlet temperature of the source, ◦C; Δ*T*2—The difference between the outlet temperature of the sink and the inlet temperature of the source, ◦C.

**Figure 4.** The T–H diagrams of different source and sink configurations for heat pump application. (**a**) Gradual slope; (**b**) Steep slope; (**c**) Medium slope.

**Figure 5.** The ideal T–S diagram of the heat pumps (**a**) JCHP, (**b**) VCHP and (**c**) TCHP.
