Effects of Fin Parameters on Gas-Side Heat Transfer Performance of H-Type Finned Tube Bundle in a Waste Heat Recovery Boiler

Alfa Laval Aalborg Oy designs and manufactures waste heat recovery systems utilizing extended surfaces. The waste heat recovery boiler considered in this thesis is a water-tube boiler where exhaust gas is used as the convective heat transfer medium and water or steam flowing inside the tubes is subject to cross-flow. This thesis aims to contribute to the design of waste heat recovery boiler unit by developing a numerical model of the H-type finned tube bundle currently used by Alfa Laval Aalborg Oy to evaluate the gas-side heat transfer performance. The main objective is to identify weaknesses and potential areas of development in the current H-type finned tube design. In addition, numerical simulations for a total of 15 cases with varying geometric parameters are conducted to investigate the heat transfer and pressure drop performance dependent on H-type fin geometry. The investigated geometric parameters include fin width and height, fin spacing, and fin thickness. Comparison between single and double tube type configuration is also conducted. Based on the simulation results, the local heat transfer and flow behaviour of the H-type finned tube is presented including boundary layer development between the fins, the formation of recirculation zone behind the tubes, and the local variations of flow velocity and temperature within the tube bundle and on the fin surface. Moreover, an evaluation of the effects of various fin parameters on heat transfer and pressure drop performance of H-type finned tube bundle has been provided. It was concluded that from the studied parameters fin spacing and fin width had the most significant effect on tube bundle performance and the effect of fin thickness was the least important. Furthermore, the results suggested that the heat transfer performance would increase due to enhanced turbulence if the current double tube configuration is replaced with single tube configuration, but further investigation and experimental measurements are required in order to validate the results.

Lactobacillus plantarum strains isolated from naturally fermented sausages and their technological properties for application as starter cultures

In the present study, technological properties of L. plantarum strains isolated from naturally fermented sausages manufactured in the South region of Brazil were investigated in order to obtain a starter culture. The technological properties evaluated were the following: ability to growth at different pH values, at different temperatures, in different salt concentrations and in the presence of commercial curing salt, fast production of acid, determination of D - and L - lactic acid; nitrate reductase activity; antagonistic activity and stability of the isolated cultures after fermentation, concentration, and freeze-drying process. The isolated strains showed effectiveness to improve technological properties as starter cultures.

Study of bacteria Gluconobacter sp.: isolation, purification, phenotypic and molecular identification

The importance of the study of acetic bacteria, on species of the Gluconobacter genus is based on its industrial application, as these possess the capacity of bioconversion of sorbitol to sorbose, enabling the process of vitamin C production. The study involved samples collected in industries of soft drinks, flowers, fruits and honey, followed by purification, phenotypic identification, molecular identification with the use of primer defined from Nucleotide Sequence Database consultation. Strains preserved were identified as members of the Acetobacteraceae family, Gluconobacter genus. 110 strains had been isolated of substrate: Pyrostegia venusta (ker-gawler), honey, Vitis vinifera (grape), Pyrus communis (pear), Malus sp. (apple) and in two samples of soft drinks. Of this total 57 strains had been recovered in manitol medium (manitol, yeast extract, peptone), 12 in YMG medium (glucose, manitol, yeast extract, ethanol, acetic acid), 41 in enrichment medium (De Ley and Swings) and later in the GYC medium (glucose, yeast extract and calcium carbonate). 68 strains were identified as Gram negative bacilli rods. Of these, 31 were characterized biochemically as belonging to the Acetobacteriaceae family as they were catalase positive, oxidase negative and producers of acid from glucose. The characterization of these strains was complemented with the biochemistry tests: gelatin liquefaction, nitrate reduction, indole and H2S production, oxidation of ethanol to acetic acid and molecular tests for genus identification. Only eight strains were characterized as pertaining to the Gluconobacter genus. The strains are maintained in collection cultures at the Microbiology Laboratory of the Biology Department at the São Paulo State University (UNESP) in Assis, stored in malt extract at -196 ºC.

Study of the flash drying of the residue from soymilk processing - "okara"

The objective of this research project was to study the drying of soymilk residue in a pneumatic flash dryer, using response Surface Methodology (RSM), and to evaluate the quality of the dried residue. Soymilk residue, also known as okara, was provided by a Brazilian soymilk factory. RSM showed that for a 120 second drying cycle, the lower the residue moisture contents (y) obtained, the higher the recirculation rates (x1), regardless of the air drying temperature (x2), and it could be expressed by the equation y = 7.072 - 7.92x1, with R² = 92,92%. It is possible to obtain okara with 10% of moisture (dwb) under the condition x1=1.25, equivalent to RR = 61%, with air drying temperatures ranging from 252 °C to 308 °C. The dried okara obtained through Central Compound Rotational Design (CCRD) presented a centesimal composition similar to the okara dried in a tray dryer, known as the original okara. There were significant variations (p < 0.05) in the Emulsifying Capacity (EC), Emulsion Stability (ES) and Protein Solubility (PS) between the dehydrated residues obtained. It was concluded that the flash drying of okara is technically feasible and that the physicochemical composition of the residue was not altered; on the contrary, the process promoted a positive effect on the technological functional properties.

Studies of chemical and enzymatic characteristics of Yacon (Smallanthus sonchifolius) and its flours

Due to the importance of studies on yacon related to health, its in natura pulp, in natura peel, pulp flour, and peel flour were chemically analyzed in terms of its centesimal composition, specific minerals, total dietary fiber and fractions, pH, total soluble solids, total titratable acidity, tannins, oxalic acid, and nitrate. The polyphenoloxidase and peroxidase enzymatic activities were evaluated for in natura pulp and peel only. Yacon pulp and peel flour presented average yield of 7.94% and 10.86%, respectively. The in natura pulp presented a higher moisture and carboydrate content and lower lipid, protein, total dietary fiber, and ash than those of the peel flour. The same pattern was observed for pulp flour when compared to peel flour. The highest tannin, nitrate, and oxalic acid levels were found in the peel flour, 15,304.5 mg.kg-1, 1,578.3 mg.kg-1, and 7,925.0 mg.kg-1 (wet weight), respectively. The polyphenoloxidase and peroxidase enzymes presented higher enzymatic activity in the yacon peel. Based on the results obtained, it can be said that the yacon and its derivatives are important dietary carbohydrate and mineral sources and contain antinutritional substance contents lower than those harmful to health.

Spirulina platensis: process optimization to obtain biomass

Spirulina platensis is a photoautotrophic mesophilic cyanobacterium. Its main sources of nutrients are nitrate, urea, and ammonium salts. Spirulina cultivation requires temperature, light intensity, and nutrient content control. This microalgae has been studied and used commercially due to its therapeutic and antioxidant potential. In addition, several studies have reported its ability to use CO2, its immune activity, and use as an adjuvant nutritive factor in the treatment of obesity. The objective of this study is the production of biomass of S. platensis using different rates of stirring, nitrogen source, amount of micronutrients, and luminosity. A 2(4) experimental design with the following factors: stirring (120 and 140 RPM), amount of nitrogen (1.5 and 2.5 g/L), amount of micronutrients (0,25 and 0,75 mL/L) (11 and 15 W), and luminosity was used. Fermentation was performed in a 500 mL conical flask with 250 mL of culture medium and 10% inoculum in an incubator with controlled stirring and luminosity. Fermentation was monitored using a spectrophotometer (560 nm), and each fermentation lasted 15 days. Of the parameters studied, luminosity is the one with the highest significance, followed by the amount of nitrogen and the interaction between stirring and micronutrients. Maximum production of biomass for 15 days was 2.70 g/L under the following conditions: luminosity15W; stirring, 120 RPM; source of nitrogen, 1.5 g/L; and micronutrients, 0.75 mL/L.

Biomass production by Arthrospira platensis under different culture conditions

In biotechnological processes, the culture media components are responsible for high costs and exert a strong influence on the cyanobacteria behavior. The objective of this study was to evaluate the Arthrospira platensis growth potential for biomass production under different cultivation conditions using an experimental design. Three factors that are important for cyanobacteria growth were evaluated: sodium bicarbonate (9 to 18 g/l), sodium nitrate (1.25 to 2.5 g/l), and irradiance (20 to 120 µmol photons/m2.s–1). The results showed that the concentration of NaNO3 in the A. platensis medium can be reduced, resulting in increased concentrations of biomass produced. There was a higher biomass production due to the increase in the concentration of NaHCO3 and irradiance, mainly when these two factors varied tending towards the highest values studied. The results demonstrate the potential to produce Arthrospira platensis with lower costs and effluent generation without affecting cultivation performance.

Veden puhdistus mikro-organismisovelluksilla (EM Mudball®)

Vesistöjen rehevöityminen on maailmanlaajuinen ongelma. ”Effective microorganisms (EM)” -teknologian väitetään mahdollistavan ravinteiden poiston vesistä luonnonmukaisten mikro-organismien avulla. Työn tavoitteena on selvittää kyseistä teknologiaa hyödyntävien EM-mutapallojen soveltuvuutta suomalaisten luonnonvesien sekä jätevesien ravinteiden poistamiseen. Kirjallisuusosassa selitettiin EM-teknologian toimintaperiaate sekä esitettiin EM-mutapallojen koostumus. Tässä osassa selvitettiin myös teknologian käyttökohteita. Lisäksi perehdyttiin Suomen vesistöjen tilanteeseen sekä EM-teknologian mahdollisiin hyödyntämiskohteisiin. Kokeellisessa osassa seurattiin 6 eri vesinäytteen ravinnepitoisuuksien muutosta EM-mutapallon käytön aikana. Osaa näytteistä säilytettiin jääkaapissa, jotta päästiin lähemmäs Suomessa vallitsevia olosuhteita. Analysoidut ravinteet olivat nitraatti, sulfaatti, fosfaatti ja typpi. Tuloksien mukaan EM-mutapallojen käyttö poisti pääsääntöisesti vesinäytteistä nitraatin. Sulfaatin poisto sen sijaan oli huomattavasti heikompaa. Paria näytettä lukuun ottamatta sulfaattipitoisuudet eivät laskeneet lähtökonsentraation alle, vaikka ajoittaista laskua tapahtuikin. Fosfaattipitoisuudet näytteissä olivat yleisesti hyvin pieniä, eivätkä ylittäneet määritysrajaa kokeen aikana ollenkaan. Ainoastaan fosfaattia sisältäneessä synteettisessä näytteessä tapahtui fosfaattipitoisuuden laskua, joka kuitenkin palautui lähes alkuperäiselle tasolle koejakson lopussa. Näytteiden typpipitoisuuksien kasvun aiheutti käymistuotteena muodostuva ammonium, jonka takia myös näytteiden pH nousi. Kokeet vahvistavat aiempia tutkimustuloksia, joiden mukaan EM-mutapallo hajoaa kahden viikon kuluttua niiden lisäämisestä vesinäytteisiin. Aikaisemmista tutkimuksista poiketen tämän kokeen mukaan EM-mutapallot näyttäisivät toimivan paremmin viileämmässä lämpötilassa. Kokeen perusteella EM-teknologian hyödyntäminen voisi olla potentiaalinen vaihtoehto tulevaisuudessa Suomen vesistöjen nitraatin poistoon.

Osmotic priming methodologies in relation to the physiological performance of rangpur lime seeds (Citrus limonia Osbeck)

Several mechanisms have been used to promote rapid germination of citrus seeds and uniform seedling emergence. We evaluated the effects of osmotic priming on the physiological performance of Rangpur lime seeds (Citrus limonia Osbeck). Seeds were treated with 30 g of Captan and 10 g of Tecto 600 in 20-litre batches and stored, without drying, at 10 ºC and 50% relative humidity for periods of 3, 6 and 9 months. After each period, seeds were primed at 25 ºC, in the light, by immersion in Poliethylenoglicol (PEG 6000), potassium nitrate (KNO3) and 70% PEG 6000 plus 30% KNO3, all at an osmotic potential of -1.1MPa, for priming periods of 3, 6, 9 and 12 days. Percentage germination, tray emergence and the emergence rate index (ERI) were evaluated. Priming in PEG 6000 solution, independent of priming period, or in KNO3 or PEG 6000 plus KNO3 for up to 9 days, were efficient at improving the physiological performance of seeds stored for up to 3 months. Osmotic priming appears to be a promising technique for improving the physiological quality of Rangpur lemon seeds.

Effects of temperature and pre-germinative treatments on seed germination of Talinum triangulare (Jacq. ) willd (Portulacaceae)

The objective of this study was to evaluate the effects of temperature, substrate and pre-germinative treatments on T. triangulare seeds. Four temperatures (constant 20, 25, 30 °C and alternate 20-30 °C) and two types of seeding (on paper and between paper), with light, were evaluated. The pre-germinative treatments evaluated included: immersion in water (24 hours), immersion in 6% hypochlorite solution (1 hour), immersion in 0.2% potassium nitrate solution (24 hours), immersion in 0.05% gibberellin solution (24 hours) and the control (untreated seeds). The highest germination percentage was observed at the alternate temperatures of 20-30 ºC, but with no significant difference between the substrates at this temperature. Soaking seeds in KNO3 gave the highest percentage germination and germination speed index (GSI), which differed from the other treatments except for soaking in water. Pre-soaking of T. triangulare seeds favors germination and may be done only in pure water, resulting in a more rapid and uniform germination.

The crystal and molecular structure of bis (pyridoxamine) copper (II) dinitrate monohydrate

The crystal structure of Cu(PM)2(N03hoH20 (where PM is pyridoxamine, CSHI2N202) has been determined from three dimensional x-ray diffraction data. The crystals are triclinic, space group pI, a = 14.248 (2), b = 8.568 (1), c = 9.319 (1) 1, a = 94.08 (1), e = 89.73 (1), y~~ 99.18 (1)°, z = 2, jl(MoK) = 10.90 em-I, Po = 1.61 g/cm3 and Pc = 1.61 g/em3• The structure a was solved by Patterson techniques from data collected on a Picker 4-circle diffractometer to 26max = 45°. All atoms, including hydrogens, have been located. Anisotropic thermal parameters have been refined for all nonhydrogen atoms. For the 2390 independent reflections with F ? 3cr(F) , R = 0.0408. The results presented here provide the first detailed structural information of a metal complex with PM itself. The copper atoms are located on centres of symmetry and each is chela ted by two PM zwitterions through the amino groups and phenolate oxygen atoms. The zwitterionic form found in this structure involves the loss of a proton from the phenolate group and protonation of the pyridine ring nitrogen atoms. The two independent Cu(PM)2 moieties are symmetrically bridged by a single oxygen atom from one of the nitrate groups. The second nitrate group is not coordinated to the copper atoms but is central to an extensive hydrogen bonding network involving the water molecule and uncoordinated functional groups of PM.

Some ecological factors affecting the input and population level of total and faecal coliforms and salmonella in Twelve Mile Creek, Lake Ontario and sewage waters near St. Catharines, Ontario

Some Ecological Factors Affecting the Input and Population Levels of Total and Faecal Coliforms and Salmonella in Twelve Mile Creek, Lake Ontario and Sewage Waters Near St. Catharines, Ontario. Supervisor: Dr. M. Helder. The present study was undertaken to investigate the role of some ecological factors on sewage-Dorne bacteria in waters near St. Catharines, Ontario. Total and faecal coliform levels and the presence of Salmonella were monitored for a period of a year along with determination of temperature, pH, dissolved oxygen, total dissolved solids, nitrate N, total phosphate P and ammonium N. Bacteriological tests for coliform analysis were done according to APHA Standard Methods by the membrane filtration technique. The grab sampling technique was employed for all sampling. Four sample sites were chosen in the Port Dalhousie beach area to determine what bacteriological or physical relationship the sites had to each other. The sample sites chosen were the sewage inflow to and the effluent from the St. Catharines (Port Dalhousie) Pollution Control Plant, Twelve Mile Creek below the sewage outfall and Lake Ontario at the Lakeside Park beach. The sewage outfall was located in Twelve Mile Creek, approximately 80 meters from the creek junction with the beach and piers on Lake Ontario. Twelve Mile Creek normally carried a large volume of water from the WeIland Canal which was diverted through the DeCew Generating Station located on the Niagara Escarpment. An additional sample site, which was thought to be free of industrial wastes, was chosen at Twenty Mile Creek, also in the Niagara Region of Ontarioo 3 There were marked variations in bacterial numbers at each site and between each site, but trends to lower_numbers were noted from the sewage inflow to Lake Ontario. Better correlations were noted between total and faecal coliform population levels and total phosphate P and ammonium N in Twenty Mile Creek. Other correlations were observed for other sample stations, however, these results also appeared to be random in nature. Salmonella isolations occurred more frequently during the winter and spring months when water temperatures were minimal at all sample stations except the sewage inflow. The frequency of Salmonella isolations appeared to be related to increased levels of total and faecal coli forms in the sewage effluent. However, no clear relationships were established in the other sample stations. Due to the presence of Salmonella and high levels of total and faecal coliform indicator organisms, the sanitary quality of Lake Ontario and Twelve Mile Creek at the sample sites seemed to be impaired over the major portion of the study period.

Tintype of Unidentified African American Woman Leaning on Chair [n.d.]

A small tintype of a young Black woman dressed in white. The date, location and name of the photographer are unknown. This tintype was among the family memorabilia belonging to Iris Sloman Bell, of St. Catharines, Ontario. Relatives of the Sloman - Bell family are descended from former American slaves."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html

Tintype of Two Young Women, Seated, with Man [n.d.]

A small tintype of three unidentified individuals, two women, seated, and a young Black gentleman, standing. The date, location and name of the photographer are unknown. This tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. The Sloman - Bell families have relatives who were former American slaves who came to Canada. They later settled in the London and St. Catharines areas of Ontario."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html

Tintype of African American Gentleman Seated on Stool [n.d.]

An unidentified man poses for his portrait seated on a stool in this undated black and white tintype photograph. This tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. Relatives of the Bell - Sloman family include former Black slaves from the United States who settled in Canada."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html