The plastic poly(ethylene terephthalate) is the most widely produced thermoplastic and is used in over 50% of all textiles. This plastic is derived from petroleum products and recycling can reduce the consumption of these raw materials and have a lower overall carbon footprint. The chemical recycling of PET involves the conversion of the polymer into corresponding monomers that are easier to purify and can ideally be reincorporated into existing polymerization processes. There are three chemical routes to depolymerize PET into monomers used for its production: glycolysis, methanolysis, and hydrolysis. We present an overview of these three technologies and highlight how differences in physical and chemical properties of the reactants and products lead to fundamental differences in process design. We use a combination of industrial literature review and design knowledge to develop complete process configurations for each depolymerization pathway. We present heat integration concepts and process intensifications that can further reduce energy demand of the respective processes. We are able to provide a comparison of the different routes from a process design perspective and describe specific waste feeds and applications where certain designs have advantage. We demonstrate heat integrated continuous PET depolymerization processes can be expected to consume between 6,000 – 10,000 kJ/kg PET regardless of the depolymerization route.