THUMBS-UP: D3.5 OPTIMIZED COMPOSITE SORBENT, MATERIAL MANUFACTURING PROCESS AND GUIDELINES FOR UPSCALE AND REPLICATION

D3.5 Optimized composite sorbent, material manufacturing process and guidelines for upscale and replication represents the report describing the activities carried out in the framework of Task 3.2 of the project. It was fully dedicated to the optimization at lab-scale of a composite sorbent material for thermochemical energy storage and to its analysis related to the long-term stability, manufacturing process scalability and corrosiveness against reference construction materials. The activity started from the selection of the reference materials, namely, active salts and matrices in which the salt is expected to be embedded. Following the target of the project, a novel material manufacturing process, based on a single step sol-gel procedure able to produce directly a silica gel embedding the salt was proposed. Nevertheless, the achieved lab-scale results turned out to be diffi cult to effi ciently implement at large scale. For this reason, a more robust impregnation method was proposed. The activity was then shifted to the assessment of the most promising composite sorbent composition, using mesoporous silica gel as reference matrix varying the active salt, the amount of salt and the impregnation procedure. The experimental activity, fully performed at lab-scale, was supported by a joint eff ort in terms of thermochemical, morphological and structural characterization of the produced material, among the active partners in the task. The result of this analysis was the selection of a material composition employing CaCl2 as active salt and the mesoporous silica gel matrix as support. The amount of embedded salt was selected being 25 wt.%, representing the best compromise between long-term stability and energy storage density. Starting from these results, the scaling-up process was implemented by NAN in their facility, coming to a process able to manufacture up to 100 kg/week of composite sorbent. The diff erent scaling-up stages were carefully supervised by all the partners, verifying the quality of the produced material. This resulted in 1 ton of composite manufactured for the prototyping phase of the project. An assessment of the production cost showed an expected cost of 2 €/kg of composite, being a promising starting point for the future industrialization of the process.