Processing biomass requires four major steps (pretreatment, fermentation, separation and purification) achieved by dedicated plants called biorefineries. These highly specialized structures cannot cope with the high variability of the whole biomass supply chain. Thus, providing agility to biorefineries is a key challenge to foster biomass processing. The goal is to design a virtual biorefinery as a collective network supported by the servitization of unit operations and the reuse of existing devices. In this regard, the first step described in this paper aims to gather and organize knowledge about a given local area (stakeholders, services) and the existing transformation process operations (inputs, outputs) through a framework. To this end, two metamodels are proposed: one to collect and structure the required information about the local area; one to organize the knowledge about the transformation processes. Their use is illustrated by a use case provided by a municipalities community located in South-West France.