The main objective of this research is the study drying kinetics and thermodynamic properties kelp using heat pump technology. effects independent variables temperature (20–50 °C), air velocity (0.3–1.3 m/s), humidity (20–50%), thickness (0.8–4.2 mm) on time, moisture uniformity, effective diffusivity (Deff), activation energy (Ea), enthalpy (ΔH), entropy (ΔS), Gibbs free (ΔG) were investigated...