Integrated Process Design and Economic Evaluation of Waste-to-Biomaterial Conversion: Hydroxyapatite Production from Blue Crab Shells using Aspen Plus - Aldi Nugroho Nugroho; Tobing Gumelar; Silma Elvaretta Aska; Vita Fatichah Rizqiyah; Villia Lidzati Kamilah; Maharani Sugito Rosanti; Dimas Gilang Venanto; Haykal Nur Fajri Ramadhan; Eva Oktavia Ningrum; Ummu Zahroh Ma'mun (IPTEK The Journal of Engineering, 2025)