Qatar Foundation Annual Research Conference Proceedings Volume 2014 Issue 1

Food security is field of major research and investigation to improve and find new resource production systems for a continuously growing world population. The State of Qatar, being arid and with limited arable lands, is increasingly reliant on imported food products and has recently engaged in extensive efforts to advance its challenging strategy to sustainably enhance its food security. Microalgae, found in the local environment and adapted to a wide range of environmental conditions, are considered promising candidates to play a central role in this food security strategy since neither arable land nor freshwater are needed for its cultivation. We aim in this study to identify the species and culture conditions for obtaining microalgal biomass as a source for feedstock production. Tetraselmis and Nannochloris isolates were selected from the Qatar University Culture Collection of Cyanobacteria and Microalgae (QUCCCM) based on preliminary results and extensive available literature review. Salinity and CO2 enrichment experiments were conducted at several levels (i.e. 35, 40 and 45 psu salinities and 3%, 5% and 10% CO2 enrichment), using a photobioreactor cultivation system. Results suggest that 35 psu salinity and 5% CO2 enrichment cultivation conditions are favorable for the protein hyper-producer Tetraselmis strain, while 40 psu salinity and 3% CO2 enrichment are more suitable for the lipid hyper-producer Nannochloris strain. Mineral uptake differed between the two species and between different salinities and CO2 enrichment culture conditions. Tetraselmis contains a higher amount of calcium, while Nannochloris contains a higher amount of potassium. Mineral profiles of the two species responded differently to salinity and CO2 enrichment culture conditions. Biochemical characterization of the obtained biomass suggests that a feed blend using both Tetraselmis and Nannochloris biomasses would provide high quality products with high protein contents, while supplying animals with essential fatty acids (i.e. PUFAs) and mineral ingredients. Recommendations for future research and development efforts are discussed.

Micro algae are a single celled biomass with a very high potential in the biobased economy. In algal biomass cultivation, the harvesting step (i.e., separation of the dilute single cell algae from the growth medium) is a considerable part of the capital and operational cost. These processes typically require the use of high amounts of chemicals and/or a significant energy input. A second important point of attention in algae cultivation is water recycle. Due to the low concentration of the algae in the cultivation (ca. 0,2 g/l dry algae in open ponds and 2 g/l in photobioreactors), large amounts of water need to be processed to produce algae paste. For example in open pond cultivation a production installation of 1000 ton dry algae per year requires about 700 m³/h water to be processed. Thus for large scale installation medium recycle is a sine qua non. A solution that tackles both issues simultaneously is the submerged flat panel membrane system. The membrane system is used as the first dewatering step in a hybrid system of algae harvesting with centrifugation as final concentration. This technology has the potential to lower energy and investment costs compared to centrifugation alone. The technology furthermore has major advantages on water recycling as > 95 % of the water needs to be removed to produce a 20 % paste of algae. As the membranes don't add any chemicals and remove all suspended solids and bacteria, the technology is very promising toward medium recycle. Submerged membrane filtration is preferred over other membrane filtration technologies (e.g. crossflow filtration), due to its low energy demand and low shearing forces. Membrane fouling is controlled by the cleaning effect of coarse bubbling aeration. Additionally, the flat panel membranes used in this study are backwashable (patented flat sheet membrane envelopes with an integrated permeate channel, IPC). The algae filtration experiments were performed on both lab and pilot-scale submerged reactors with different membranes (MF and UF), algae species (Nannochloropsis, Pavlova, Isochrysis, Phaeodactylum), algae concentration, filtration regimes and filtration cycle times and aeration flows. The results show that membrane operation with backwashing results in higher stable fluxes than operation with only relaxation which is the normal operating mode for submerged membranes. Moreover the flux of UF membranes is more stable than MF membranes and that shorter filtration times result in higher stable fluxes (in the backwashing regime). Aeration flow turned out to be critical towards achievable flux levels and the characteristics of the algae suspension. VITO will further develop and optimize the technology for harvesting and water recycle on pilot scale and demonstration scale. The latest information on the developments of this technology will be presented.

MICROBIAL DESALINATION CELL: A SUSTAINABLE APPROACH FOR BRACKISH WATER DESALINATION AND WASTEWATER TREATMENT WITH BIOELECTRICITY GENERATION Surajbhan Sevda1, Zhen He2, Ibrahim M. Abu-Reesh*1 1Department of Chemical Engineering, College of Engineering, Qatar University P.O. Box 2713, Doha, Qatar 2Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA *Corresponding author: [email protected] Abstract The shortage of the fresh water has become a more and more serious issue because of the rapid increase in human population and resource consumption. Although water is an abundant natural resource available in the earth, only 3% of the water is potable and the other 97 % (seawater) is not potable. To meet the demand for fresh water, desalination processes are used for removing salt from seawater. The major limitation with current desalination processes (membrane or thermal) is the high energy requirement. Therefore, new technologies are required to reduce energy consumption by desalination. Among the new developments, microbial desalination cell (MDC) has a great potential as a low-energy desalination process with significant benefits such as simultaneous wastewater treatment. MDC is a new technology in which salt water can be desalinated without using any external energy source (except that for pumping water). The exoelectrogenic-bacteria in the anode of an MDC oxidize biodegradable substrate in wastewater and transfer the electrons to the anode electrode. Those electrons flow through an external circuit to the cathode electrode where they are used to reduce external electron acceptors such as oxygen. Unlike microbial fuel cell (MFC) from which an MDC is derived, an MDC contains a middle chamber between the anodic and cathodic chambers formed by a pair of anion exchange membrane and cation exchange membranes. This middle chamber works as a desalination chamber like that in an electrodialysis (ED). The potential difference between the anode and cathode electrodes drives the migration of ions out of the desalination chamber, with cations (Na+) migrating to the cathodic chamber and anion (Cl-) moves to the anodic chamber. As a result, salts are removed from the saltwater. MDC technology could be attractive in Qatar and the region because of strong demand for cost effective desalination technologies for desalination of seawater through linking to conventional desalination process, or of brackish water. This paper will introduce the fundamentals and future prospects of MDC technology.

Improved Acid Stimulation in Carbonates: impact of acid types and flow rate on reactive transport mechanisms Oussama Gharbi1, Stefan Goedeke2, Mohammed Al-Sammarraie2, Nour El Cheikh Ali1, Saqer Al-Shahwani2, Pascal Chenevière1, Dominique Guérillot2 and Philippe Julien1 1 TOTAL E&P Golfe ltd - Qatar branch , 2 Qatar Petroleum Research & Technology Centre Acid stimulation in carbonates is a reactive transport mechanism where transport dynamics are coupled with reaction kinetics. Accurate description of reactive transport in heterogeneous porous media still represents a scientific challenge. One of the main objectives of acid stimulation treatments in carbonate reservoirs is to achieve a good zonal coverage with the acid, especially to unlock low permeability hydrocarbon regions. However, field applications show that acid stimulation leads to a poor increase of permeability in the targeted region as well as an increase in water production. In this joint research program between Qatar Petroleum and TOTAL, we aim to develop and test novel pumping sequences of fluids in order to improve acid stimulation efficiency in mature carbonate reservoirs. We performed high pressure and temperature single and dual core flooding experiments over a range of four different carbonate samples with different permeabilities and pore structures. Live and emulsified acids were used as well as Relative Permeability Modifiers (RPMs) and particle-laden diverters. Changes in permeability were measured in real time during the injection across the length of the cores. In addition, pre and post-injection micro-CT scanning allowed the visualization of different dissolution patterns (mainly dominant wormholing). Changes in porosity induced by the chemical reactions were also deduced based on image analysis. We compared the response of different acid types and assess the impact of RPMs on brine and oil flow. Results show the impact of flowrate and acid type on reactive transport mechanisms. The measurements of pore volume to breakthrough are discussed. The insights into different pumping strategies can be used to different other applications such as carbon storage in heterogeneous carbonates.

The Al Shaheen oil field is located approximately 80 km north-east of Qatar in the Arabian Gulf. The area hosts a highly productive marine environment due to a combination of complex currents and high temperatures. The diverse marine fauna is exemplified by one of the world largest aggregations of whale sharks (Rhincodon typus) that return to this area every summer. The research has demonstrated that whale sharks come here to feed on the high concentration of tuna mackerel spawn (Euthynnus affinis). Over the past four years the Qatar Whale Shark Research project (www.qatarwhalesharkproject.com) has used novel acoustic and telemetric technologies to describe the demography and behaviour of the Arabian Gulf whale shark population. More than 70 whale sharks have been fitted with acoustic tags to be able to identify their main aggregation sites within the Al Shaheen oil field. Photo identification of more than 300 individuals and satellite telemetry tracking has confirmed the Arabian Gulf as a highly important habitat. Detailed hydrological modelling has been initiated in order to better describe the currents that influence the spawning location of the tuna mackerel and if they influence the movements of the whale sharks in the Arabian Gulf. Acoustic data loggers have also been deployed for monitoring the diurnal and seasonal presence of marine mammals based on their vocalisation. Several species of dolphins have already been identified including Indo-pacific bottlenose dolphin (Tursiops aduncus), Long-beaked common dolphin (Delphinus capensis), and Dwarf spinner dolphin (Stenella longirostris roseiventris). The high concentration of these species in the Al Shaheen field might be a result of the reef-effect associated with offshore platforms. Images taken by Remote Operated Vehicles demonstrate extensive marine growth on the subsea structures that again attracts numerous pelagic species. More than 30 fish species have been identified so far including top predators such as Scalloped hammerhead(Sphyrna lewini), Blacktip shark (Carcharhinus limbatus), and Zebra shark (Stegostoma fasciatum). The research is based on collaboration with both international and Qatar based researchers representing universities, government and the oil industry. The data will make it possible for relevant authorities and industry operators to take appropriate action in order to secure the protection of biodiversity in the Arabian Gulf.

The purpose of this study is to better understand the geochemical behavior of Re and Os in petroleum in the context of the Re-Os radiometric age dating of petroleum. Rhenium (Re) and osmium (Os) are organophile elements. For this reason, the 187Re-187Os radiogenic system is well adapted to date organic-rich rocks such as source rocks. Absolute datation of source rocks is more particularly important for Petroleum Systems knowledge. Recently, it was suggested that the Re-Os system could also be used to date hydrocarbon generation (Selby and Creaser, 2005). However, the meaning of the obtained age is ambiguous. This is mainly due to the lack of knowledge about the geochemical behavior and the speciation of Re and Os in oils. Specifically, using the Re-Os geochronometer requires a complete system reset (corresponding to an age of 0) during the hydrocarbon generation and the system to remain closed through geological times and events. Moreover, additional conditions are necessary as the isotopic homogenization of oils at the scale of a basin and the chemical fractionation of Re from Os to obtain samples with various Re/Os ratios. If one of these steps is not fulfilled, no age can be measured, that why it is essential to develop a better understanding of the geochemical behavior of these elements. Several key events may have a significant influence on Re and Os partitioning such as the formation, primary and secondary migration or alteration of petroleum in reservoirs. Formation was already studied through artificial maturation (Rooney et al., 2012). However, the other aspects have to be investigated. To try to better understand Re-Os chemical behavior in hydrocarbons, we performed experiments to simulate possible events occurring during migration and reservoir storage such as asphaltenes partial deposition (Mahdaoui et al., 2013) and contact with an aquifer (Mahdaoui et al., submitted). After chemical treatment of samples, Re and Os concentrations were determined by isotope dilution. Re and Os isotopic compositions used for concentration calculations were determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and by Negative Thermal Ionization Mass Spectrometry (N-TIMS), respectively. Results of our experiments enable us to constrain the processes which control most likely Re and Os content in oil and thus they provide a firm basis to characterise Petroleum System events that are actually dated by the Re-Os geochronometer, e.g.: genesis, migration or reservoir filling. REFERENCES Mahdaoui, F., Reisberg, L., Magali, P., Poirier, Y. Behavior of Re and Os during contact between an aqueous solution and oil. Submitted Mahdaoui, F., Reisberg, L., Michels, R., Hautevelle, Y., Poirier, Y. and Girard, J.-P., 2013. Effect of the progressive precipitation of petroleum asphaltenes on the Re-Os radioisotope system. Chemical Geology, 358, 90-100. Selby, D., Creaser, R.A., 2005. Direct radiometric dating of hydrocarbon deposits using Rhenium-Osmium isotopes. Science, 308, 1293-1295. Rooney, A.D., Selby, D., Lewan, M.D., Lillis, P.G., Houzay, J.P., 2012. Evaluating Re-Os systematics in organic-rich sedimentary rocks in response to petroleum generation using hydrous pyrolysis experiments. Geochimica et Cosmochimica Acta, 77, 275-291.

Sawda Nathil is one of a series of inland depressions that extend nearly continuously from Umm Bab along the Saudi Arabia-Qatar border to Khor Al Adid. Six to eight thousand years ago, these depressions were marine embayments that separated the peninsula of Qatar from the Kingdom of Saudi Arabia. Narrow land bridges connected Qatar, restricting the migration of people and animals. These embayments infilled rapidly with dune sands blown southward from Qatar. Since then, they have become progressively more evaporitic. Inland depressions like Sawda Nathil represent unique environments of Qatar. Most depressions are close to or below sea level. This brings groundwater to the surface in the driest parts of Qatar. Evaporation to salt saturation creates thick gypsum and salt crusts (sabkhas), as well as shallow hypersaline ponds (salinas) with spectacular microbial gypsum stromatolites. The present ground surface is a mosaic of relict marine facies, deflated dune sands, inland sabkhas, and salinas. The study area is located along the eastern margin of the Sawda Nathil depression. Four shallow cores were taken at the sabkha area surrounding the salina. A total of 30 sediment samples and an additional 5 samples from the stromatolitic salina deposits were collected for thin section and X-ray diffraction (XRD) analyses. Radiocarbon (AMS) and optically stimulated luminescence (OSL) age-dating were carried out on three samples. Scanning electron microscope (SEM) analyses was carried out on samples from a gypsum stromatolite. Radiocarbon and optically stimulated luminescence dates for marine shells and the enclosing sediment provide ages of approximately 6,000 years before present (yr BP) and coincide with a well-documented highstand, when sea level was 2 to 4 meters higher than present. These beach deposits are interpreted to represent remnants of the post-glacial Holocene transgression which began about 18,000 years ago and reached its highest level during the Late Holocene about 6,000 years ago. The sabkhas (gypsum and salt flats) and salinas (saline ponds) are younger, associated with infilling of the embayments, related to a drop of sea level to present day. SEM examination of gypsum stromatolite samples show gypsum crystals developing in close spatial association with microbial biofilms (filamentous structures). Whether this is a purely passive microbially-influenced gypsum mineralization process or whether the microorganisms actively control the mineralization process in order to obtain ecological advantages, remains to be evaluated. Studying and documenting different types of microbial sedimentary structures preserved in gypsum is of particular interest, not only in the field of petroleum geology, but also in the field of exobiology. Whereas carbonate minerals are quantitatively the most important sediment for preserving morphological biosignatures on Earth, the most relevant chemical sediments on Mars are likely sulfate minerals. Gypsum has been widely detected on Mars and is interpreted to have formed under evaporitic conditions broadly similar to those characterizing terrestrial sabkha and salina environments of Qatar.

Dolomite is an important constituent of many economically important gas and oil reservoir rocks. Studies conducted in modern environments combined with microbiological laboratory experiments have shown that microbes and their extracellular polymeric substances (EPS) play an important role for the formation of primary dolomite at Earth's surface conditions. These studies showed that, at low temperature, Mg is incorporated into the carbonate mineral exclusively in the presence of specific organic molecules. However, because the organic molecules involved in the mineralization process rarely survive metamorphism and are usually not preserved in the carbonate mineral, identifying microbial dolomite in ancient rocks represents a challenging task. It remains, as yet, unclear what percentage of sedimentary dolomite is a primary microbially mediated precipitate vs. a secondary replacement product that formed during diagenesis or at high temperatures during metamorphism. A useful approach for evaluating the microbial origin of ancient dolomite is that of searching for microfossils and other microstructures of biological origin associated with the dolomite crystals. Here, we present the results of scanning electron microscopy (SEM) investigations of various ancient sedimentary dolomites. Several investigated samples include abundant filamentous microstructures that we interpret to be mineralized EPS. In some cases, these filaments form a well-structured alveolar pattern, whose architecture appears too complex to be the result of an abiotic process. In order to reinforce our interpretation, we also investigated modern biofilms, which include microstructures of EPS that are morphologically identical to the mineralized and preserved EPS in ancient dolomites. In some rare cases, we also found microfossils (i.e. mineralized cells) in close spatial association with the dolomite crystals. These occurrences are remarkable, considering that it is commonly thought that only chert has the potential of preserving the soft tissues constituting microbial cells. Although we cannot prove conclusively that the fossilized cells and EPS mediated the formation of the adjacent dolomite crystals, our results indicate that dolomite formation took place in environments where microorganisms and biofilms were an important component of the depositional setting. The "microbial factor", which has been proven to be essential for the precipitation of dolomite at low temperature in modern environments, may, therefore, have also been active during the formation of these ancient carbonates.

The United Nations 2010 Climate Change Conference in Cancun (The Cancun Agreements) reached a verdict on climate change as one of the greatest challenges of our time and that deep cuts in emissions are required to prevent its potentially devastating effects. Energy is currently a vital global issue given the likely depletion of current resources (fossil fuels) coupled with the demand for higher-performance energy systems. Today the world face an urgent need for renewable energy technologies; solar power—the direct exploitation of the ultimate energy source for nature and our planet—should be one of these. Organic electronics has made enormous scientific and commercial progress over the last 10 years, mainly driven by the potential of applications such as light-emitting diodes(OLEDS) for display and large area lighting, field effect transistors (OFETs) for flexible backplanes and e-paper and solar cells (OPV) for large area energy generation. Much of this work has been motivated by the fact that organic semiconductors can combine the superb mechanical and processing characteristics of plastics with a variety of printing techniques, enabling large-area, low-cost manufacturing. Bulk-heterojunction organic photovoltaic (BHJ OPV) cells are a potential competitor to amorphous silicon-based technologies. Because of the ready availability of carbon feedstocks and numerous and flexible synthetic pathways, organic compounds are attractive materials for solar cell applications. OPV cells have experienced tremendous progress in performance during the last three years, with power conversion efficiency (PCE) now routinely surpassing 9%, attracting industries to commercialize these high-tech devices. A promising strategy to improve the performance in FETs and OPVs has been the inclusion of fused aromatic heterocycles into the conjugated polymer backbone. One such fused heterocycle of considerable recent interest and promise, is dithienopyrrole (DTP). Low band gap co-polymers of N-alkylated or N-arylated DTPs show promise as the active components in OPV and FETs. However their device performance has been limited by the propensity for the DTP to be readily oxidised. In addition to limiting the ambient stability of FETs under operating conditions, the low ionisation potential of DTP containing polymers limits the available open circuit voltage available in bulk heterojunction OPV devices, thus limiting efficiency. In the light of this we were interested in developing analogues of DTP which would demonstrate improved oxidative stability, by replacement of the flanking thiophene groups with more electron deficient thiazole groups to produce a fused dithiazolopyrrole (DTzP). We have developed a route to novel dithiazolopyrrole monomers and incorporated them in donor acceptor co-polymers, they have been successfully co-polymerised with thiophene, selenophene, thienothiophene and bithiophene by microwave assisted Stille polycondensation. The resulting polymers exhibited small optical band gaps combined with low lying HOMO energy levels, high ionization potential and good solubility in most common organic solvents and show promise for use in optoelectronic devices. Further investigations into their photovoltaic performance are ongoing which would be coupled with industrial partners in Qatar.

DNA barcoding, as a fast and reliable technique, has already gained tremendous popularity among the biologists for identification of animals. Like other animal groups, an international consortium named Fish Barcode of Life (FISH-BOL) has been initiated with a target of barcoding all the fish species. DNA barcoding is a molecular approach to identifying species by comparing sequences of a short DNA fragment of an unknown sample derived by polymerase chain reaction (PCR) against the sequence of known species through alignment and phylogenetic tree construction. As a barcode, approximately 650 bp from the 5' end of Cytochrome oxidase 1 (CO1) gene of the mitochondrial genome has been found to be most effective in identifying fish and other animals with a high discrimination power. The objective of the study was to identify Sheirii (Lethrinus nebulosus) based on mitochondrial CO1 gene sequence-based DNA barcode. Sheirii samples were collected from Al Khor by the Department of Fisheries. Total DNA was extracted from the fin tissue using QIAGEN tissue/blood DNA extraction kit. PCR was conducted using universal primer pairs designed for the mitochondrial CO1 barcode region of animals. Both strands of the PCR-derived fragment of approximately 650bp were sequenced using a Big Dye Terminator kit (Applied Biosystems) and an ABI 3130 Genetic Analyzer. The molecular identification of the species was performed by comparing 601 nucleotide sequences of sheirii CO1 gene with those of relevant species collected from the GenBank using basic local alignment search tool (BLAST). The BLAST alignment of the sequence obtained in the present study showed 100% identity with the CO1 gene sequence of Lethrinus nebulosus available in the gene bank. Thus, the sheirii sample from Qatar has been correctly identified by the DNA barcoding technique. The findings of this study will be included in the databank of the FISH-BOL that are available for molecular identification of fish eggs, larvae and stomach contents of other predator fishes, processed fish and fish products in Qatar and worldwide. Molecular identification and assessing biodiversity would help implementing the national plan for sustainable utilization and conservation of local fish species.