Camilla Sommerseth, former PhD candidate at the Department of Materials Sciences and Engineering, now a scientist at SINTEF, won the Best Carbon Paper Award at the ICSOBA conference. ISCOBA – The International Committee for Study of Bauxite, Alumina & Aluminium – organized the conference in Quebec, Canada in October 2016.
Sommerseth and her coauthors received the award for the article “The Effect of Varying Mixing and Baking Temperatures on the Quality of Pilot Scale Anodes – A Factorial Design Analysis” by Camilla Sommerseth, Rebecca Jayne Thorne, Arne Petter Ratvik, Espen Sandnes, Hogne Linga, Lorentz Petter Lossius and Ann Mari Svensson.
The article is based on Sommerseth’s work as a PhD candidate. She defended her thesis in April 2016 – “The Effect of Production Parameters on the Performance of Carbon Anodes for Aluminium Production”. Ann Mari Svensson was her supervisor. Egil Skybakmoen (SINTEF), Arne Petter Ratvik (SINTEF) and Lorentz Petter Lossius (Hydro) were co-supervisors.
Ferrochrome is a widely used alloy of iron and chromium, essential in the stainless steel industry. We try to find a way of producing ferrochrome using natural gas instead of coal. This would give a more cost effective and environmentally friendly production process.
The raw material for ferrochrome comes from chromite mines. It is possible to get a fairly high content of chromium and iron out of these processed rocks, but they are still rocks, and that’s where metallurgy comes in action. In my studies, I synthesize “artificial rocks” (see Figure 1).
The whole purpose of ferrochromium production is to remove the oxygen contained in the chromite (O4 in FeCr2O4) and keep what we want: the two metals that are iron and chromium.
The oxygen removal process involves many different steps, as it is increasingly difficult to remove oxygen when we’ve removed most of it. One of these steps involves coals, being basically carbon. Carbon reacts with the oxygen in the chromium, forming carbon monoxide, leaving what we want.
Energy saving potential
The reaction with coal and chromite is usually carried around 1400°C, which means that a lot of energy is needed. As a part of my PhD project, I look at ways to use natural gas (methane) instead of coal in this process. The reaction with methane and chromite would be carried at temperatures lower than 1200°C. That is a lot of energy saved in heating! Besides, using methane could be more effective, potentially removing more oxygen than carbon would have (see Figure 2). This would limit the need for the last and most energy intensive step… and this is also mine to find out!
Differences in the raw material
Unfortunately, the composition of the raw material vary in many different ways: In addition to iron, chromium and oxygen, numerous minerals – like magnesiochromite, hercynite, spinel – just to mention some are mixed in the material.
Two different mines usually produce very different ores, and the composition of the ores can also change dramatically in different places of a single mine! These impurities, even present in small quantities, can have an important impact on the metal extraction processes and the reaction with methane.
Controlling the uncertainties
In order to make valid results from my research, I must have knowledge and a control of the composition. As a part of my study I therefore make my own materials to study. I feel like recreating simplified nature!
How we create these materials will be a topic for my next blog post.
How methane reacts with the chromite
With the proper raw material, the reactions between chromite and methane can finally be studied. At this stage, many parameters can influence the reaction. This includes the material composition, the temperature, the gas composition, the duration, and many others. Besides, the reaction mechanism itself is not clearly identified yet.
But at high temperatures, methane gas molecules are fairly unstable and tend to break up in hydrogen molecules and graphite. It is also at high temperature that methane gas is the most reactive and the most likely to carry a reaction with the ore, pulling oxygen from the ore as carbon monoxide and seeping in carbon to form carbides (see Figure 3). We need to vary the parameters in order to obtain the second scenario.
By testing a wide range of these parameters, we hope to learn more about how methane behaves in contact with chromite, and how the various impurities influence this behavior. Maybe the addition of other gases during the reaction, or the use of a particular ore with a specific impurity will make the perfect match?
This week is matriculation week at NTNU. The Faculty of Natural Sciences and Technology warmly welcomes approximately 500 new students.
Earlier this week around 7000 new students gathered at Gløshaugen in Trondheim to hear NTNU rector Gunnar Bovim and others wish them welcome to NTNU. NTNU in Ålesund and NTNU in Gjøvik had similar events.
After the gathering, the students met with their new faculties.
Ready to meet the new international students. Photo: Pernille Feilberg / NTNU
After a long time without writing any posts, I am still here, ready for some new words. Last time I mentioned that I would say something about scientific life. I am at the same place, in the same conditions, surrounded with new scientific challenges, which currently stops me from writing my paper.
I would like to introduce PhD candidates’ most common opponent before the official defense and its name is time, which runs so fast that you cannot keep up. To me, it seems like the amount of work increases with time while challenges remain in spite of good progress. I am very sure that most of you immediately got the point why I have not written any posts since last summer. I am not trying to justify myself, but that is reality. Anyways, I think it will be useful (at least for some of you) to have an overview of PhD life and activities at NTNU Trondheim after more than one and a half years from the start (middle of the PhD programme).
The first thing that came to my mind when I passed the last exam was that I will have more time for myself and my research, which will exponentially influence the development of my PhD work. This is logical, it makes sense, but now I see that logic does not work all the time.
It takes a lot of time
Mostly, this looks like sine and cosine functions, which goes up and down. I can say for myself that things are going more or less ok, but not with the same acceleration as I was expecting. Now I see that PhD progress is unpredictable and it is good to be aware of this before starting. Sometimes things do not look so difficult, but it takes a lot of time, and sometimes huge issues can be solved quickly, sometimes by picking up a new idea after an unintentional mistake which was made during an experiment. As one of my colleagues always says: “You never know why it is good”.
Bad results are also good results
Each time you don’t succeed with an experiment, and struggle for a long time, think twice before getting upset, because “bad” results are actually “good”. This is the chance to figure out something new, maybe to discover a new phenomenon, or to realize a “missing element” in your knowledge. Since PhD work is a learning process, like everything else in life, a positive attitude and good ideas followed by a proper plan will usually give good output sooner or later. My motto is: keep on going, be patient and keep it positive.
My research topic is based on thermoelectric materials, which is part of the national project called Thelma. Thermoelectric materials are able to transform heat into electricity and vice versa. The project is based on nano-structuring for improving the energy efficiency of thermoelectric generators and heat-pumps, where my aim of work is focused on studies on developing technology for new generators for commercialization. This project is interesting and in spite of many challenges and tough goals, we still have good fun.
Besides the Thelma project, there are many other amusing projects where other colleagues are working. Some of these are related to batteries, solid oxide fuel cells, biomaterials, piezoelectric, etc. As far as I know, several new colleagues will start soon as new PhD and post-doc. positions will be available.
Currently, I am waiting for June when I will visit the summer school in Limoges (France), then a conference on a cruise through the northern part of Norway, which will probably be exciting. The plan is also to go somewhere on an internship by the end of the year. Next time I write, you will find out more about it.
How can LPMO enzymes transform cellulose into essentials like food and fuel? By the use of NMR (Nuclear Magnetic Resonance) spectroscopy we have found important answers to this question. In the future, these findings might help us control and optimize the production processes in biorefineries.
The cornerstone of the green shift is technology that allows us to convert biomass (organic matter from living organisms) into food, materials, chemicals, feed and fuels. This is not a simple process either. Biomass comes in many different forms; the most abundant of which is cellulose: a polymer that is the main component of plants and trees. Naturally, cellulose is very stable and difficult to break down, which is a great advantage for the trees that produce it, but poses a daunting task for industrial biomass conversion in biorefineries.
Here is where a group of enzymes (tiny molecular machines) known as lytic polysaccharide monooxygenases (LPMOs) comes into play. LPMOs were discovered in 2010 by Vincent Eijsink’s group at NMBU at Ås, and have ever since been in the scientific spotlight. They have been called “tiny wood chip machines” and “reverse photosynthesizers”. Indeed, LPMOs are fascinating enzymes. They are produced by certain bacteria and fungi, and use oxygen, electrons and copper to make nicks on cellulose chains. These nicks cause cellulose to lose some of its stability, making it more susceptible to degradation and making biorefineries more efficient.
The purpose of my PhD project is to use NMR spectroscopy to study the function of LPMOs in greater detail, as the interactions between the different factors (cellulose, copper, oxygen, electron donors, LPMO) must be optimized in order to maximize the efficiency of the LPMO reaction.
In recent papers, we have used brand-new NMR instrumentation installed at Gløshaugen to study the interplay between an LPMO, woody materials (like cellulose) and CDH (another enzyme that fuels the LPMO reaction with electrons).
Crucial step of the reaction discovered
Together with our collaborators in NMBU, Aalborg University, BOKU Vienna and SLU Uppsala, we showed that the LPMO must first receive electrons from CDH before binding to cellulose. This is a crucial step of the reaction and implies something else that is extraordinary about LPMOs: that they are somehow able to store electrons.
Future control and optimization
This finding may be applied to control and optimize the flow of electrons to LPMOs, an important feature to maximize LPMO activity in biorefineries.
For decision making, it is important to understand the long-term consequences of forest loss on both the biodiversity and the human population.
Some days “at the office” means more than just a computer and an R script, even to a theoretical ecologist. My doctoral project is carried out in collaboration with research groups from Rio Claro, Brazil. Because of this, once in a while I get to have a total change of scenery at work; from fjords and fjelds to neo-tropical forests and vast plantations.
The Brazilian Atlantic Rainforest
In my PhD project, I want to gain knowledge on the links between forest fragmentation, biodiversity and ecosystem services. Brazilian Atlantic rainforests are under intensive land-use pressure set by agriculture and forestry (less than 10 % of original forest cover remain).
The high level of fragmentation in these rainforests leads to biodiversity loss and degradation of ecosystem functioning, and thereby of the ecosystem services that human population benefits from.
Interactions between species
Based on the spatial insurance hypothesis, it can be assumed that larger networks of species-to-species interactions will maintain the availability of these ecosystem services.
To connect biodiversity dynamics and forest fragmentation, I will use a database that includes studies over a long time period and a large area on the coastal rainforests of Brazil.
Trees and seed dispersing animals
The dataset covers many species communities from trees and birds to dung beetles and large mammals. In my project, I will be looking at the interactions within and between communities, such as between trees and seed dispersing animals.
As an example, large mammals spread large seeds of trees that store a lot of carbon from the atmosphere. The carbon storage is considered to be an important ecosystem service that benefits the human population via climate control.
When the large mammals are hunted to extinction or disappear because the forest fragments are too small to support their populations, also the big trees disappear and are replaced by smaller trees with lower carbon storage capacity.
The effect of fragmentation
The study sites in question cover areas with higher and lower degrees of fragmentation so it will be possible to evaluate the effect of fragmentation on the communities.
I will utilize newly developed statistical models to illustrate whether plant-animal interactions, namely seed dispersal and pollination networks, are influenced across the forest fragmentation gradient.
I predict that the networks are simpler in more fragmented landscapes and provide ecosystem services in a smaller extent compared to the more continuous parts of the ecosystem.
Whether my predictions are right or not, we will see as I continue the work with my PhD project.
Extracting oil and gas from subsea production fields is a complicated process. Today it is done from offshore platforms, but the development in the oil and gas industry is towards unmanned production units placed on the seabed.
Moreover, subsea operations will allow production in deeper waters, as well as in remote areas with severe weather conditions, where the size, weight and energy demands of the installations are key-elements.
Harmful to the pipelines
Acidic gases, such as carbon dioxide (CO2) and hydrogen sulfide (H2S), and water vapor are impurities found in the natural gas coming from the reservoir and they must be removed before it can be sold. The water can corrode the pipelines and lead to the formation of ice crystals, called hydrates, which can clog the pipelines.
Acidic gases, in the presence of water, can form acids that corrode pipelines and other equipment. H2S, which is a colorless gas with a characteristic odor, is in addition poisonous and explosive. Therefore, safe operations necessitate the removal of these impurities.
Onshore treatment of the gas
There are two well-established industrial absorption processes onshore for this purpose:
removal of H2S/CO2 with amine-based solvents.
removal of water with glycol-based solvents.
In both cases, the gas meets the liquid solvent inside a column, which captures the desired impurities. Then, the solvent carrying the acid gas or the water enters a desorption column, where the impurities are removed and the solvent is ready to be used again, i.e. the solvent is regenerated.
Offshore, glycols are used for hydrate inhibition while, when selective removal of H2S is required, a liquid solvent, called triazine, is typically used. Triazine is a non-regenerative solvent and can treat only gases with low concentrations of H2S. However, treatment of gases with high concentrations of H2S would be enabled by the use of a regenerative solvent.
My PhD work
In my work as a doctorate candidate, I will help develop a new process for simultaneous removal of H2S and water from the natural gas, using a solvent system, which can be regenerated. The regeneration will take place topside and the separation will take place subsea, unmanned.
In addition to moving oil and gas production towards safer and more effective processes, the combination of the two processes in one will also lead to a more compact, smaller installation with lower energy requirements as well as it will allow for production from high H2S-concentration gas fields that are closed today.
In this way, new energy resources will be made available for a society with steadily increasing energy needs.
When the universe was created, strong magnetic fields existed. The same type of magnetic fields can be created in experiments when heavy ions are made to collide. We study how elementary particles behave in these fields. The theoretical understanding of this is important in order to explain the experiments as well the history of the universe.
Elementary particles, such as protons, neutrons, and pions are composed of different types of quarks and anti-quarks. For example, a proton is composed of two u-quarks and one d-quark, while a pion is built out of a u-quark and an anti d-quark.(see Figure 1). Elementary particles that consist of quarks and/or antiquarks are called hadrons.
When a hadron gas is heated to extreme temperatures, the hadrons “melt”. This means that the quarks and antiquarks are no longer bound together, but can move freely around. This is called
a phase transition from the hadronic phase to a so-called quark-gluon plasma phase.
The temperature required for this phase transition is approximately 4 trillion degrees Celsius, which is many orders of magnitude higher than the temperature in the core of the Sun, which
approximately 15 million degrees Celsius.
Temperature drop after the Big Bang
The opposite of the melting process mentioned above, took place shortly after the Big Bang.
Immediately after the Big Bang, the temperature was so high that a quark-gluon
plasma existed. As the universe expanded, the temperature dropped rapidly, and approximately 10 microseconds after the Big Bang it was so “cold” that hadrons were formed.
This is schematically illustrated in Figure 2.
Heavy-ion collision experiments at CERN
A quark-gluon plasma can be created in the lab by colliding two heavy ions, for example
gold or lead ions. This kind of experiments are carried out at the Large Hadron Collider at CERN, Geneva. The energy of the particles in these experiments is so high that the associated temperature created in the collision is sufficient for the hadrons to melt (see Figure 2).
It is known that very strong magnetic field existed in the early universe. Strong magnetic fields are also created in some of the heavy-ion collision experiments. The theoretical understanding of how hadrons behave in these fields, is therefore important in order to explain the experiment as well the history of the universe.
Elementary particles in strong magnetic fields In a recently published paper, we have discussed in detail the properties of elementary particles in strong magnetic fields at temperatures in the vicinity of the phase transition. The material that we have covered includes the contributions from a large number of authors. It also includes the PhD work of William Naylor in collaboration with Anders Tranberg (UiS) and Jens O. Andersen.
This new knowledge is a step of the way towards understanding what happened in the early universe.
Figure 3 shows how the melting temperature of a pion gas varies with the temperature. In this model calculation, the melting temperature increases as the magnetic fields grows. The green curve corresponds to massless pions while the blue curve corresponds to pions with the mass found in nature.
When I try to explain to people what I do for my research, they seem to be more interested in how I catch and approach my subjects, than what I detect in them. However, it is pretty cool what I can tell about a bird by studying its feathers.
My name is Mari Løseth and I’m an environmental detective, also called an ecotoxicologist. This is a fancy title for someone who studies contamination in wildlife. For my PhD project at the Bird Ecotoxicology group (IBI, NTNU) I investigate environmental contamination in birds. I want to find out how new, current-use and regulated compounds released into the environment can affect birds feeding high up in the food chain. I want to know how they are coping. Are they more stressed with higher contamination load? Or will the compounds they are exposed to challenge their immune system?
I wanted to work with birds because they are fascinating and complex creatures. They are long lived, intelligent, beautiful and the coolest thing of all – they can fly. The birds I study, the white-tailed eagle (Haliaeetus albicilla) and the glaucous gull (Larus Hyperboreus) are both top predators in their habitats.
Looking at them, it might be hard to imagine that the inconspicuous glaucous gull could be anywhere near as superior a hunter as the huge white-tailed eagle with its impressive claws and over 2 meter wingspan. Truth is – despite being around half the size – the gull is equally fierce. The two species have quite similar diets – varied, opportunistic and seasonal. Prey species are often fish, other seabirds and mammals.
Feeding on such a high level in the food chain is great as you usually don’t have to compete for food. Unfortunately, it also has some down sides.
When feeding high up in the food chain, the birds risk exposure to high concentrations of several environmental contaminants. Some of these contaminants possess bioaccumulative properties. This means that the concentrations of the compound will increase in the exposed individual, because the uptake rate is higher than the excretion rate. Some of these compounds can also increase with each step up in the food chain, resulting in very high concentration in predatory species. This process is
As both the white-tailed eagle and the glaucous gull are feeding on the top of the food chain they can be exposed to high contamination levels, even though they live in non-urbanized and remote areas. This is due to the physical and chemical properties of the compounds. They can be volatile or bind to particles and thus be transported long-distances with wind and/or water currents away from the pollution source, reaching remote areas such as the high Arctic.
The compounds I investigate are the ones making our daily products water- and dirt repellent, non-flammable and long lasting, such as perfluorinated compounds and flame retardants. This is done by introducing the chemicals with the desired properties into consumer products. And as we produce, use and dispose of the products, these chemicals can be released into the environment. At this point they become environmental chemicals, contamination or pollution – and they can potentially harm vulnerable ecosystems already under a lot of stress from urbanization, deforestation and climate change.
I aim to look at differences in contamination patterns in different habitats to see if some locations are more exposed than others. When doing this, we usually look at concentrations in blood plasma. This time I’m also investigating the compounds in the feathers, in hope that this can replace the blood samples and the need to capture and restrain the birds when collecting samples.
To see how the birds are coping with the contaminants, I look at their general health and immune functioning. I do this by exposing extracted lymphocytes (a type of white blood cells present in the blood) to an immune challenge and observing the response. In order to measure how stressed the birds are, I detect their major stress hormone – corticosterone – in their blood and feathers. The blood will tell me how stressed the birds are right before and in the actual sample situation, while the feather sample will allow me to assess how stressed they have been over a longer period (during the period of feather growth).
How can you detect this in feathers?
Well, during the growth, the feather is continuously supplied with blood though the “stem” of the feather, the rachis. As the feather continues to grow, the blood supply of the new grown feather part is shut off, and the hormones and compounds that were supplied to the feather remain there forever. This process of incorporation continues until the feathers if fully grown and the blood supply is disconnected. The feather thus integrates contaminants and hormones present in the blood during the whole period of feather growth. This makes the feather an ideal sample matrix – in an ideal world.
A lot of research needs to be done in order to find the right method to detect all the desired compounds in the feather, and this is something I aim to do during my PhD.
I hope to see that the birds are coping well, and that their health and immune system will not be affected by their contaminant load, even if they become stressed as I approach them in the field for another session of measures and selfies.