Initial process studies carried out in Aspen Plus on an integrated thermochemical conversion process are presented herein. In the simulations, a hydrothermal liquefaction (HTL) plant is combined with a biogas plant (BP), such that the digestate from the BP is converted to a biocrude in the HTL process. This biorefinery concept offers a sophisticated and sustainable way of converting organic residuals into a range of high-value biofuel streams in addition to combined heat and power (CHP) production. The primary goal of this study is to provide an initial estimate of the feasibility of such a process. By adding a diesel-quality-fuel output to the process, the product value is increased significantly compared to a conventional BP. An input of 1000 kg h−1 manure delivers approximately 30–38 kg h−1 fuel and 38–61 kg h−1 biogas. The biogas can be used to upgrade the biocrude, to supply the gas grid or for CHP. An estimated 62–84% of the biomass energy can be recovered in the biofuels.