READi-PtL

A successful climate-neutral energy transition requires two things in order to sustainably reduce CO₂ emissions: the efficient storage of excess renewable energy and its use in the mobility sector, among others. The X-Energy sub-project READi-PtL is pursuing this goal and linking the electricity and mobility sectors. To this end, organic residues and electrical energy are converted into liquid hydrocarbon using a two-stage READi^TM process. Electrolysis hydrogen is used to produce liquid hydrocarbon from fatty waste such as deep-frying fat, which serves as the basis for sustainable (liquid) fuels. 

The plan is for these power-to-liquid (PtL) fuels to achieve a so-called drop-in quality to conventional fuels, i.e. to have the same quality in order to replace them in the long term. This will also overcome the limits of conventional biofuels with regard to blending into conventional fuels.

The aim is to include the mobility sector in a climate-neutral energy transition without short-term changes to current technical drive systems or infrastructures.

The solution is to develop a new and cost-effective two-stage technology. In the first stage, bio-oils are obtained thermochemically from sustainable resources containing triglycerides (e.g. used cooking oils). In the second stage, these are then refined into liquid hydrocarbons using hydrogen obtained from electricity. This in turn forms the basis for usable fuel products.

The process engineering basis of the first stage is the READi^TM process, a new, particularly cost-effective thermochemical process for converting biogenic problematic and waste materials into bio-oils, which can be processed into drop-in fuels with comparatively little effort. The READi^TM process is a joint development of the Competence Center for Renewable Energies and Energy Efficiency (CC4E) at HAW Hamburg and the partner company Nexxoil.

Results

The READi^TM process was successfully verified on a small pilot scale. The new pilot plant was then technically developed on the basis of the process data generated. As part of the scaling up of the READi^TM process, it was transferred to the large pilot scale. A plant with a reactor volume of 200 liters was designed for this purpose. The construction of the new plant in the machine hall of the Faculty of Life Sciences at HAW Hamburg is currently in preparation.

In parallel to the activities relating to the READi^_TM process, the second process stage (catalytic hydrogenation) was investigated in the high-pressure laboratory at HAW Hamburg. As part of these activities, a new tubular reactor was installed and put into operation. Work on continuous catalytic hydrogenation in a fixed bed is currently being carried out. High-purity hydrocarbons have already been successfully produced.