Project 1: Making Biogas a CO2 Sink using Carbon Mineralization

The aim of the Project P1 is to develop a process that can convert CO2-neutral biogas to a CO2 sink. The implementation of the Kohlendioxid-Speicherungsgesetz (Carbon dioxide storage law) from the 24th of August 2014 has demonstrated that underground CO2 storage is not met with public acceptance in Germany. Hence, a new method must be developed to recycle the CO2 present in biogas. One method would be to use the CO2 to mineralize the ash from power stations. The potential of this method was verified by a diploma thesis written at the research chair. Preliminary investigations demonstrated that not only CO2, which was bound by carbonation, but also heavy metals were permanently immobilized under ambient conditions. Thus, treating ash using gaseous CO2 upgrades biogas to a CO2 sink, enabling the recovery of valuable substances from the ash and modifying the ash characteristics allowing for easy disposal. Four unresolved aspects of the aforementioned CO2-recycling path must be investigated in the graduate school:

(1)    Transferability of the hitherto results to ash from biomass combustion and waste incineration
(2)    Feasibility of simultaneous H2S capture in biogas
(3)    Necessary process modifications: reduction of water demand in the immobilization of heavy metals and the recovery of resources such as CaCO3 and MgCO3
(4)    Ecological and economical advantage of the new process

 

Doctoral Candidate: Alexander Sakowski

First (Main-) Supervisor: Prof. Dr. Norbert Mollekopf

Second Supervisor: Prof. Dr. Dominik Möst