Disputation
Due to the travel restriction caused by the ongoing Pandemic, the Disputation will be held digital using Zoom.
The Chair of Defense will lead the Disputation and the Defense technician will solve technical issues.
Ex auditorio questions: The Chair of Defense will invite the audience to ex auditorio questions. These can be asked orally, by clicking "Participants - Raise hand" in the Zoom menu. The Zoom-host will grant you to speak in the meeting.
Order the Dissertation as PDF from this email address with the name of the Candidate: a.c.gartner@kjemi.uio.no
Trial lecture
26th. of October 10:15 AM, Zoom
''Ammonia as energy carrier in a carbon free future economy - challenges and potential"
Conferral summary
Denne Ph. D.- oppgaven omhandler studier av materialer og systemer for varmelagring som kan brukes til gjenvinning av spillevarme. For første gang er nøytron-avbildning og nøytron-spredningsteknikker brukt for å studere kinetikk, og kjemiske og fysiske egenskaper til slike systemer.
Main research findings
Roughly, three-quarters of the energy produced in the world ends up as waste heat. However, the waste heat can be harvested, stored and reused using specially built heat storage reactors for high- or low-temperature applications. This thesis attempts to provide new insight into metal halide ammines as a potential heat storage system with a high energy efficiency. These materials undergo desorption and absorption of NH3-gas in a thermochemical reaction, which results in an uptake or release of heat, respectively.
This work shows the study of the thermochemical heat storage reactor prototype with the metal halide ammine salt Sr(NH3)xCl2 for low-temperature applications below 100 °C. The changes in kinetics and chemical- and physical properties during NH3 cycling were characterized by neutron imaging and scattering techniques. A honeycomb-shaped heat exchanger within the reactor was optimized based on the results from the neutron imaging investigations. The mechanical stresses and heat transfer within the heat exchanger were studied in detail. Overall, this project demonstrates for the first time the possibility of applying neutron imaging and scattering techniques for analysis of thermochemical heat storage materials and systems.