Thesis (M.S.)--Case Western Reserve University, 2009 / Abstract Department of Physics Title from OhioLINK (viewed on 20 April 2009) Available online via the OhioLINK ETD Center

Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Currently the three main algae strains that are manufactured commercially are Chlorella, Spirulina and Dunaliela salina, which are produced for biomass and bioproducts. Photobioreactors (PBR) allow the exploitation of over 50 000 known microalgae species with over 15 000 novel compounds having been chemically identified to date. Many of these algae could be sources of high-value products which are produced using a method that delivers them from renewable resources. Designing an optimal photobioreactor is a complex process because a large array of variables is included in the design, with several of the variables interacting with each other directly. The interactions of most of these variables have not been established. The initial information that is available is inadequate because most photobioreactors have been tested on a laboratory scale and the information given does not include the manufacturing materials, the size of tubing used and other design variables. Before designing a photobioreactor, it is important to understand the best conditions for the production of algae because these have a direct influence on the requirements. In order to produce algae biomass under the specific conditions, one has to investigate current photobioreactors that have been designed in order to establish whether they are capable of optimum production under the production conditions; determine possible factors that could influence the production negatively and how they could be prevented; and undertake a cost analysis to determine whether the production of algae is an economically viable process using the specific reactor. All of these criteria have to be met for a photobioreactor to be viable in the production of algae biomass. Currently a Bubble column reactor is considered to be the best design for a photobioreactor and also the most scalable. Due to the limited information available, testing was conducted to determine the effect of: 1) different manufacturing materials, 2) the gas dispersion unit, 3) the diameters of the tubing and 4) the density. Bubble column reactors were used to test the effects of the four variables and were considered to be the most important aspects in the design. For testing these variables and their interaction, Chlorella Vulgaris was used because it is one of the most popular algae species used for production currently. As temperature and the availability of light play a large role in the production of algae, all testing was done in a laboratory environment to ensure small temperature changes and the constant availability of light. The reactors that were tested were made of PVC couplings, with the clear tubing used being made of either PVC or acrylic tubing. Enriched air was supplied at a 5% volume per volume ratio of CO2, with a flow rate of 0.02 volume per volume per minute (vvm) for the 50 mm diameter reactors and 0.36 vvm for the 90 and 110 mm diameter reactors. Two gas dispersion units were used to determine whether they would have any effect on the production. The gas dispersion units create small bubbles to ensure a high surface area to volume ratio and thereby they allow for maximum CO2 and O2 mass transfer. A growth rate of 0.14 gram per litre per day was found to yield the best production of all the reactors and configurations that were tested. The 50 mm diameter reactors showed the best growth followed by the 110 mm diameter reactors. The 90 mm diameter reactors all had a negative growth rate which appeared to be due to an insufficient gas flow rate. The 50 mm reactors had the best growth rate of 0.14 and 0.10 grams per litre per day for the acrylic tubing, while 0.08 grams per litre per day was achieved with PVC tubing. The 110 mm reactors had a highest growth rate of 0.05 grams per litre per day with PVC tubing. It was found that the 50 mm and 90 mm reactors showed a better performance with acrylic tubing while the 110 mm reactors showed a better performance with PVC tubing. The gas dispersion unit is affected by the gas flow rate, the density, the diameter of the tubing and the material that is used. The gas dispersion units’ effect is dependent on the diameter of the reactor seeing that the 50 mm reactor shows better performance with the small unit, while the 110 mm reactor shows better performance with the large unit, due to the gas flow rate that is required in the reactors. Because the gas flow rate and gas dispersion unit directly affect the agitation, the optimal density is affected directly due to the availability of light and therefore the tubing material. The gas dispersion units should fit properly into the reactor and be capable of handling the gas flow rate that is required. The diameter of the tubing does not show any effect but could have an effect under different testing conditions and could not be conclusively eliminated. The density of algae does have an effect, although most reactors showed a better production rate at a higher culture density. The scale up of the bubble column reactor creates a dead zone when a module is constructed. The scale up of a bubble column reactor could range from increasing the vertical tubing length, increasing the diameter of the tubing to adding vertical tubing to a module. The dead zone is formed at the bottom of the reactor where the module interconnects the vertical growth tubes, because these fittings are not constructed from a clear material, due to cost of such a construction. The dead zone that is created causes a large portion of algae to form a sediment, which directly affects the production of the system because it is in a dark zone of the reactor. Improved results would be obtained if the algae were kept at a homogeneous density that would ensure maximum expose to light. The ratio of gas flow rate to reactor volume and diameter of the tubing was found to be crucial. It is suspected that the 90 mm tubing reactor had a negative growth rate as this ratio was not correct. The 50 mm reactors had to be run at a much lower reactor volume per volume gas flow rate which could consist of air, carbon dioxide enriched air or other gases as required. The inclusion of the tubing diameter in the ratio is of vital importance and should be studied further. A cost analysis shows that the bubble column reactors under the tested conditions are not financially viable. A large component of the cost is carbon dioxide and medium, which is a composition of nutrients. This could be removed if a free source were obtained, which would make the system financially viable. These sources could include waste water and flue gas from industrial processes. It is recommended that a gas dispersion tube be positioned at the bottom of the reactor to ensure that no sedimentation occurs and that there is a homogeneous culture, and to maximise the production capabilities of a bubble column reactor. It is also recommended that the gas flow rate inside the reactor be studied to obtain a ratio where the volume of the reactor, the height of the reactor and the diameter of the tubing are included to obtain a sufficient rate of flow. / AFRIKAANSE OPSOMMING: Tans is daar drie belangrike alg stamme wat kommersieel geproduseer word, Chlorella, Spirulina en Dunaliela salina. Fotobioreaktors het meegebring dat meer as 50 000 bekende alg spesies met meer as 15 000 komponente tot op datum chemies geïdentifiseer is. Baie van hierdie alge kan hoë waarde produkte wees, wat met behulp van hernubare metodes geproduseer kan word. Die ontwerp van 'n optimale fotobioreaktor is 'n komplekse proses aangesien 'n groot verskeidenheid veranderlikes ingesluit moet word wat ‘n invloed op mekaar kan hê. Die interaksie van meeste van hierdie veranderlikes is nog nie vasgestel nie. Die inligting oor hierdie onderwerp is beperk aangesien die meeste fotobioreaktors in 'n laboratorium getoets is en dus nie die vervaardigingsmateriale, die grootte van buise en ander ontwerp veranderlikes insluit nie. Voordat 'n fotobioreaktor ontwerp kan word, moet die ideale alg produksie toestande verstaan word, aangesien dit 'n direkte impak op die produksie vereistes kan hê. Om alg biomassa onder spesifieke omstandighede te produseer, moet die bestaande fotobioreaktor ontwerpe ondersoek word. Daar moet vasgestel word of die bepaalde ontwerp oor die kapasiteit beskik om optimale produksie te lewer; identifisering van faktore wat produksie negatief kan beïnvloed en hoe dit voorkom kan word; en 'n koste ontleding moet gedoen word om te bereken of die produksie van alge met die geidentifiseerde ontwerp 'n ekonomies lewensvatbare proses is. Daar moet aan al die vereistes voldoen word om te bepaal of 'n fotobioreaktor lewensvatbaar is vir die produksie van alg biomassa. 'n Borrel-kolom reaktor ontwerp word tans as die beste ontwerp vir 'n fotobioreaktor geag, asook die mees aanpasbare ontwerp. As gevolg van die beperkte inligting wat beskikbaar is, is navorsing gedoen om die invloed van verskillende faktore te bepaal, naamlik: vervaardigingsmateriaal, gasverspreidingseenheid, buisdeursnee en digtheid. Borrel-kolom reaktors is gebruik om die vier belangrikste veranderlikes in die ontwerp te toets. Om die veranderlikes en hul interaksie te toets, is Chlorella vulgaris gebruik, aangesien dit een van die gewildste alg spesies is vir die produksie van biomassa. As gevolg van die belangrike rol wat temperatuur en lig beskikbaarheid in die produksie van alge speel, is al die toetse in 'n laboratorium-omgewing gedoen om temperatuur wisseling te beperk en konstante lig beskikbaarheid te verseker. Die reaktors wat getoets is, is vervaardig uit PVC koppelstukke, met die deurskynende buise wat uit PVC of akriel vervaardig is. Verrykte lug is verskaf op 'n 5% volume per volume verhouding CO2, met 'n vloei tempo van 0,02 volume per volume per minuut (vvm) vir die 50 mm deursnee reaktors en 0,36 vvm vir die 90 mm en 110 mm reaktors. Twee gasverspreidingseenhede is gebruik om hulle invloed op die produksie te bepaal. Die gasverspreidingseenhede skep kleiner borrels, om 'n hoë oppervlak area tot volume verhouding te skep en daardeur 'n maksimum CO2 en O2 massa-oordrag te verseker. 'n Groeikoers van 0,14 gram per liter per dag is gevind as die beste produksie van al die reaktors en konfigurasies wat getoets is. Die 50 mm deursnee reaktors het die beste groei getoon, gevolg deur die 110 mm deursnee reaktors. Die 90 mm deursnee reaktors het 'n negatiewe groeikoers getoon, wat moontlik toegeskryf kan word aan onvoldoende gas vloei tempo. Die 50 mm reaktors het die beste groeikoers van 0,14 en 0,10 gram per liter per dag vir die akriel buise getoon, terwyl ‘n 0,08 gram per liter per dag behaal is met 'n PVC buis. Die 110 mm reaktors het die hoogste groeikoers aangedui van 0,05 gram per liter per dag met 'n PVC buis. Daar is bevind dat die 50 mm en 90mm reaktors 'n beter prestasie met akriel buise gehad het, terwyl die 110 mm reaktors 'n beter prestasie met 'n PVC buis gehad het. Die gasverspreidingseenheid word beinvloed deur die gas vloei tempo, digtheid, buisdeursnee en die vervaardigingsmateriaal wat gebruik word. Die gasverspreidingseenhede word verder beinvloed deur die reaktor se buisdeursnee aangesien die 50 mm reaktor ‘n beter prestasie getoon het met die kleiner gas eenheid, terwyl die 110 mm reaktor ‘n beter prestasie getoon het met die groter gas eenheid, as gevolg van die gas vloei tempo wat vereis is. Die gas vloei tempo en gasverspreidingseenheid het ‘n direkte invloed op die groei van die kultuur, dus is die optimale digtheid afhanklik van die lig beskikbaarheid en dus die vervaardigingsmateriaal van die buise. Die gasverspreidingseenhede moet stewig in die reaktor pas en in staat wees om die gas vloei tempo wat vereis word te kan hanteer. Hoewel die deursnee van die buise nie 'n invloed getoon nie, kan dit 'n invloed onder verskillende toets omstandighede toon en kon nie finaal uitgeskakel word. Die digtheid van die alge het wel 'n effek, hoewel die meeste reaktors ‘n beter produksie tempo op 'n hoër kultuur digtheid toon. Die groter skaal borrel-kolom reaktor ontwikkel 'n dooie sone indien ‘n module saamgestel word. Die groter skaal borrel-kolom reaktor kan insluit: die verhoging van die vertikale buis lengte, 'n toename in deursnee van die buise en toevoeging van vertikale buise in die module. Die dooie sone het gevorm aan die onderkant van die reaktor waar die module se vertikale groei buise met mekaar verbind is. Hierdie area is uit nie-deurskynende materiaal vervaardig as gevolg van die konstruksie koste. Die dooie sone het veroorsaak dat groot hoeveelhede van die alge ‘n sediment gevorm het en ‘n direkte invloed op die produksie van die stelsel gehad het aangesien dit 'n donker sone in die reaktor gevorm het. Beter resultate kan verwag word indien die alge op 'n homogeniese digtheid gehou kan word om maksimum lig blootstelling te verseker. Daar is bevind dat die verhouding van gas vloei tempo tot reaktor volume en buisdeursnee deurslaggewend is. Die negatiewe groeikoers in die 90 mm reaktor word toegeskryf daaraan dat hierdie verhouding nie korrek was nie. Die 50 mm reaktors het op 'n laer reaktor volume per volume gas vloei tempo gefunksioneer wat kan bestaan uit die lug, verrykte lug of ander gasse soos benodig. Dit dui daarop dat die insluiting van die buis deursnee in hierdie verhouding van kardinale belang is en verder bestudeer moet word. 'n Koste ontleding toon dat die borrel-kolom reaktors onder hierdie getoets omstandighede nie finansieel lewensvatbaar is nie. 'n Groot deel van die koste is die medium, wat 'n samestelling van voedingstowwe is, en koolstofdioksied koste. Om finansieel lewensvatbaar te raak, moet hierdie kostes deur 'n gratis bron vervang word. Die bronne kan bestaan uit afval water en oortolige CO2 uit industrie. Daar word aanbeveel dat 'n gasverspreidingsbuisie aan die onderkant van die reaktor geplaas word. Dit sal verseker dat geen sediment vorm nie en 'n homogeniese kultuur gehandhaaf kan word om maksimum produksie in 'n borrel-kolom reaktor te handhaaf. Verder word aanbeveel dat die gas vloei tempo binne die reaktor verder bestudeer word om 'n verhouding tussen die volume van die reaktor, die hoogte van die reaktor en die deursnee van die buise te bepaal deur sodoende 'n voldoende tempo van vloei te verkry.

Made available in DSpace on 2016-06-02T19:32:08Z (GMT). No. of bitstreams: 1 5490.pdf: 1141768 bytes, checksum: a5a2a49b5f220f5e424dbe6dc6784e42 (MD5) Previous issue date: 2013-08-14 / Universidade Federal de Sao Carlos / Algae are organisms with which studies have been made on the uptake of carbon dioxide, as a source of lipids for research on biofuels such as fertilizers and soil. But little is known about the interaction of such organisms with higher plants. Thus, the general objective of this master thesis was to reuse the algal biomass of Selenastrum capricornutum Printz (Chlorophyceae class) e Chlorella sorokiniana Shihira e Krauss (Trebouxiophyceae class) in pelleting seed Bowdichia virgilioides, native to the Brazilian Savanna that are classified as threatened with extinction and whose wood has attributes for the furniture industry, besides the medicinal properties already reported in other studies. First, the seeds were grown in a greenhouse, with the following treatments: a) seeds naked; b) pelleted seeds with white glue based on polyvinyl acetate diluted to 8% at water and gypsum; c) seeds pelleted with glue based white polyvinyl acetate diluted to 8% at wet algal biomass of Selenastrum capricornutum and gypsum; d) pelleted seeds with white glue based polyvinyl acetate diluted to 8% at wet algal biomass of Chlorella sorokiniana and gypsum. Fungicide and insecticide were added to the silicato and gypsum for agricultural according to industry directions. The parameters mean emergence time (days), weight (g) dry and cool, length (cm) of aerial and root portions and number of nitrogen fixing nodules in the roots don t showed statistically significant difference between treatments. The variable "emergency percentage" showed that pelleted seeds with C. sorokiniana biomass as a cement material constituent showed value equivalent to conventional treatment (naked), paving the way for new studies pelleting with agal biomass of that species. As higher be the algae intracellular biochemical values, higher be the chances to achieve satisfactory results, because the seed can be use algae biochemical components at its development. In a second stage, there was pelleted seed sown in an area of brazilian savanna and the treatments were: a) naked seed; b) pelleted seeds with white glue based on polyvinyl acetate diluted to 8% at water and gypsum; c) pelleted seeds with white glue based on polyvinyl acetate diluted to 8% at wet algal biomass of Selenastrum capricornutum and gypsum with fungicide and insecticide; d) pelleted seeds with white glue based on polyvinyl acetate diluted to 8% at water and silicate for agricultural; and e) pelleted seeds with white glue based on polyvinyl acetate diluted to 8% at wet algal biomass of Selenastrum capricornutum and silicate for agricultural. Fungicide and insecticide were added to the silicato and gypsum for agricultural according to industry directions. For this experiment hood, it was observed that treatment with only gypsum had a significantly lower percentage of emergence. The treatment with silicate was considered as an effective material coating to the sucupira seed pelleting process, cultivating in savanna field. Thus, the alga Chlorella sorokiniana showed to be an efficient cementing material for pelleting process and silicate for agricultural a promising coating material, when it comes to planting in the field. / Microalgas tem sido alvo em estudos que visam à captação de dióxido de carbono. Esses microrganismos também vêm sendo utilizados como fonte de lipídios para produção de biocombustíveis e estudos relatam sua biomassa como potenciais fertilizantes de solo. Mas, pouco se sabe sobre a interação de tais organismos com vegetais superiores. O objetivo geral desse trabalho foi reutilizar a biomassa de Selenastrum capricornutum Printz (classe Chlorophyceae) e Chlorella sorokiniana Shihira e Krauss (classe Trebouxiophyceae) na peletização de sementes de Bowdichia virgilioides (sucupira preta, sucupira do cerrado), espécie nativa do cerrado brasileiro que está classificada como ameaçada de extinção e cuja madeira possui atributos para a indústria moveleira, além das propriedades medicinais já relatadas em vários trabalhos. Primeiramente, as sementes foram semeadas em casa de vegetação, com os seguintes tratamentos: a) sementes nuas (sem pélete); b) sementes peletizadas com cola branca à base de acetato de polivinila diluída a 8% em água e gesso agrícola; c) sementes peletizadas com cola branca à base de acetato de polivinila diluída a 8% em biomassa algal úmida de S. capricornutum e gesso agrícola; d) sementes peletizadas com cola branca à base de acetato de polivinila diluída a 8% com biomassa algal úmida de C. sorokiniana e gesso agrícola. Ao gesso agrícola foram acrescentados fungicida e inseticida. Tempo médio de emergência (dias), peso (g) seco e fresco, comprimento (cm) das partes aéreas e radiculares e o número de indivíduos contendo nódulos fixadores de nitrogênio nas raízes não apresentaram diferença estatística significativa entre os tratamentos. Contudo, as plântulas de sementes peletizadas com C. sorokiniana, como constituinte do material cimentante, apresentaram porcentagem de emergência equivalente ao tratamento convencional (nua). Observamos que quanto mais elevados forem os valores bioquímicos intracelulares da alga, há mais chances de obtermos resultados satisfatórios, já que a semente pode utilizar tais compostos em seu desenvolvimento. Em um segundo momento, a semeadura de sementes peletizadas foi realizada em uma área do cerrado situada no campus da Universidade Federal de São Carlos (21°57 S, 47°52 W, a 863 m de altitude), cidade de São Carlos-SP. Os tratamentos foram: a) sementes nuas (sem pélete); b) sementes peletizadas com cola branca à base de acetato de polivinila diluída a 8% em água e gesso agrícola; c) sementes peletizadas com cola branca à base de acetato de polivinila diluída a 8% em biomassa úmida de S. capricornutum e gesso agrícola; d) sementes peletizadas com cola branca à base de acetato de polivinila diluída a 8% em água com silicato para uso agrícola; e) sementes peletizadas com cola branca à base de acetato de polivinila diluída a 8% em biomassa úmida de S. capricornutum e silicato para uso agrícola. Ao silicato e gesso para uso agrícola foram acrescentados fungicida e inseticida segundo as recomendações dos fabricantes. Para este experimento em campo, observou-se que o tratamento somente com gesso agrícola proporcionou uma porcentagem de emergência significativamente menor do que o tratamento sementes nuas , sendo o silicato considerado um material mais eficiente como revestimento no processo de peletização de sementes de sucupira do cerrado cultivadas em campo. Assim, a alga C. sorokiniana mostrou-se um material cimentante eficiente no processo de peletização e o silicato para uso agrícola mostrou-se um material de revestimento promissor, em se tratando de plantio em campo.

When microalgae are exposed to changing environmental conditions, e.g., light-dark cycles or oscillations in nutrient availability (CO2, nitrogen, phosphate or silicate) they respond with metabolic changes in the carbon allocation pattern. Short time regulations in the time range of few seconds to minutes can be mirrored best by mass spectroscopy based metabolomics. However, these snap shots do not reflect the alterations in the carbon flow to the cellular macromolecules like protein, carbohydrate or lipid. In this review it is shown how the combination of FTIR spectroscopy and Chla-in-vivo-fluorescence based electron transport rates can reveal changes in the metabolic flux rates of carbon during a shift of the environmental conditions. The review will demonstrate in which time range FTIR spectroscopy can deliver significant information and how FTIR spectroscopy data can synergistically support metabolome analysis by mass-spectroscopy.

Algae offer as much as 30 times greater biomass productivity than terrestrial plants, and are able to fix carbon and convert it into a number of interesting products. The numerous challenges in algae production and use extend across the entire process chain. They include the selection of suitable algal phyla, cultivation (which takes place either in open ponds or in closed systems), extraction of the biomass from the suspension, through to optimal use of the obtained biomass. The basic suitability of aquatic biomass for material use and energy supply has been demonstrated in a large number of studies. Numerous research projects are concerned with identifying the optimal processes to enable its widespread implementation. [... aus der Einleitung]