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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Cleaner production opportunity assessment for market milk production in Atatürk Orman Çiftliği(AOÇ) facility

Özbay, Arzu. January 2003 (has links) (PDF)
Thesis (M.S.)--Middle East Technical University, 2003. / Keywords: Cleaner production, waste reduction, dairy, market milk processing.
2

Technisch-hygiënische beschouwingen over de economie van den industrieelen arbeid ...

Persant Snoep, Pieter. January 1918 (has links)
Proefschrift--Delft. / "Stellingen": 5 p. laid in. Includes bibliographical references.
3

Evaluation of cleaning procedures for allergen control in a food industry environment

Wang, Xin (Annie) January 2007 (has links)
Tegel Foods Limited produces an extensive range of poultry products which may contain various potential allergens. These include wheat, soy, milk, and egg, sometimes in combination. This research has two purposes. One was to examine three cleaning stages of processing equipments – Rinse only, Foam and rinse and Sanitise and rinse to validate the efficacy of cleaning required between production runs where the first but not the second product contains the allergen. The allergen chosen to model the cleaning efficacy was gliadin, a protein in wheat. The second aim was to quantify allergenic risk to consumers from inadequately cleaned conveyer surfaces. The commercial motives driving this research were as follows. Cleaning represents a loss in productivity and an increase in consumables costs, and if it can be minimised, this would be advantageous. The requirement to declare the possibility of cross-contamination on retail packaging can potentially adversely affect consumer response, and if these declarations can be avoided then this too would be a commercial advantage. Three approaches were adopted or developed, an ATP bioluminescence test, an ELISA test kit for gliadin, and a Coomassie Blue test to quantify protein given that most allergens are proteins. Fifteen trials were done in the High Care Zone and the Old Further Processing line of the Tegel Henderson Plant production area over a period of nine months. In a typical trial, gliadin values normalised to Uncleaned values fell from 1000 (Uncleaned) arbitrary units, to 60 (Rinse only), to 0.3 (Foam and rinse), to zero (Sanitise and rinse). Parallel ATP tests similarly showed a progressive decrease in values. Compared with Uncleaned, the relative gliadin value was less than the relative ATP value after Foam and rinse in 14 of 14 trials. After Sanitise and rinse the same result was obtained. In the equivalent trials with ATP and Coomassie Blue, after cleaning of Foam and rinse and Sanitise and rinse, the relative ATP values exceeded the relative Coomassie Blue values in four of the five trials. Therefore the considerably cheaper and simpler ATP test is not only an indicator of hygiene but also a good guide to gliadin concentration (gliadin test), and to allergen contamination in general on the basis that allergens are mostly proteins (Coomassie Blue). Modelling of second-product contamination has been done, and was based on knowledge of the absolute gliadin concentration on a typical Uncleaned conveyer surface, as established in the first part of this project. The concept of the worst-case scenario examined the highest possible risk that a sensitive consumer would be exposed to an allergenic dose of gliadin. A pickup efficiency fraction of 0.3 was assumed as an upper limit of contamination from conveyer to the surface of a previously uncontaminated chicken piece. The model showed that the highest concentration of gliadin on the second product would be 6.3 ppm which is below the legislated limit of low-gluten. Information of direct commercial interest to Tegel has been extracted from all these results, and suggestions for future research have been made.
4

Evaluation of cleaning procedures for allergen control in a food industry environment

Wang, Xin (Annie) January 2007 (has links)
Tegel Foods Limited produces an extensive range of poultry products which may contain various potential allergens. These include wheat, soy, milk, and egg, sometimes in combination. This research has two purposes. One was to examine three cleaning stages of processing equipments – Rinse only, Foam and rinse and Sanitise and rinse to validate the efficacy of cleaning required between production runs where the first but not the second product contains the allergen. The allergen chosen to model the cleaning efficacy was gliadin, a protein in wheat. The second aim was to quantify allergenic risk to consumers from inadequately cleaned conveyer surfaces. The commercial motives driving this research were as follows. Cleaning represents a loss in productivity and an increase in consumables costs, and if it can be minimised, this would be advantageous. The requirement to declare the possibility of cross-contamination on retail packaging can potentially adversely affect consumer response, and if these declarations can be avoided then this too would be a commercial advantage. Three approaches were adopted or developed, an ATP bioluminescence test, an ELISA test kit for gliadin, and a Coomassie Blue test to quantify protein given that most allergens are proteins. Fifteen trials were done in the High Care Zone and the Old Further Processing line of the Tegel Henderson Plant production area over a period of nine months. In a typical trial, gliadin values normalised to Uncleaned values fell from 1000 (Uncleaned) arbitrary units, to 60 (Rinse only), to 0.3 (Foam and rinse), to zero (Sanitise and rinse). Parallel ATP tests similarly showed a progressive decrease in values. Compared with Uncleaned, the relative gliadin value was less than the relative ATP value after Foam and rinse in 14 of 14 trials. After Sanitise and rinse the same result was obtained. In the equivalent trials with ATP and Coomassie Blue, after cleaning of Foam and rinse and Sanitise and rinse, the relative ATP values exceeded the relative Coomassie Blue values in four of the five trials. Therefore the considerably cheaper and simpler ATP test is not only an indicator of hygiene but also a good guide to gliadin concentration (gliadin test), and to allergen contamination in general on the basis that allergens are mostly proteins (Coomassie Blue). Modelling of second-product contamination has been done, and was based on knowledge of the absolute gliadin concentration on a typical Uncleaned conveyer surface, as established in the first part of this project. The concept of the worst-case scenario examined the highest possible risk that a sensitive consumer would be exposed to an allergenic dose of gliadin. A pickup efficiency fraction of 0.3 was assumed as an upper limit of contamination from conveyer to the surface of a previously uncontaminated chicken piece. The model showed that the highest concentration of gliadin on the second product would be 6.3 ppm which is below the legislated limit of low-gluten. Information of direct commercial interest to Tegel has been extracted from all these results, and suggestions for future research have been made.
5

Caustic Recovery From Highly Alkaline Denim Mercerizing Wastewaters Using Membrane Technology

Varol, Cihangir 01 September 2008 (has links) (PDF)
Recovery of caustic solution from mercerizing wastewaters of a denim producing textile mill was performed by using membrane technologies. A comprehensive characterization study was conducted to develop the treatment scheme. Highly alkaline and warm condition of wastewater has induced using membranes made of Polyethersulfone (PES). Conducted pretreatment applications such as microfiltration, flocculation and centrifuge have been found unsuccessful to improve further treatment capacities. Hence recovery studies which are UF, NF and pilot-system membrane applications have been implemented without any pretreatment. Effects of TMP and CFV on UF and NF processes were investigated and optimum operating conditions have been defined. UF has accomplished almost complete caustic solution recovery beside high COD and color retentions 84 % and 94 % under 4.03 bar TMP and 0.79 m/s CFV at 20&plusmn / 2 0C. Because of higher capacity of NF membranes also in acid and alkali recovery area, NF process has been studied in addition to UF. NF has also provided nearly complete NaOH recoveries with 92 % COD and 98 % color retentions under 4.03 bar TMP and 0.79 m/s CFV at 20&plusmn / 2 0C. Furthermore temperature effect was also studies by repeating the same processes at 40&plusmn / 2 0C considering the real operating conditions. Temperature has affected the system performance positively with regards to flux increases with insignificant loses in recovery and retention capacities. Lastly a pilot plant study has been conducted and it was found successful despite some operational difficulties due to high inorganic content and temperature of wastewater.
6

Development Of A Predictive Model For Carbon Dioxide Sequestration In Deep Saline Carbonate Aquifers

Anbar, Sultan 01 June 2009 (has links) (PDF)
Although deep saline aquifers are found in all sedimentary basins and provide very large storage capacities, a little is known about them because they are rarely a target for the exploration. Furthermore, nearly all the experiments and simulations made for CO2 sequestration in deep saline aquifers are related to the sandstone formations. The aim of this study is to create a predictive model to estimate the CO2 storage capacity of the deep saline carbonate aquifers since a little is known about them. To create a predictive model, the variables which affect the CO2 storage capacity and their ranges are determined from published literature data. They are rock properties (porosity, permeability, vertical to horizontal permeability ratio), fluid properties (irreducible water saturation, gas permeability end point, Corey water and gas coefficients), reaction properties (forward and backward reaction rates) and reservoir properties (depth, pressure gradient, temperature gradient, formation dip angle, salinity), diffusion coefficient and Kozeny-Carman Coefficient. Other parameters such as pore volume compressibility and density of brine are calculated from correlations found in literature. To cover all possibilities, Latin Hypercube Space Filling Design is used to construct 100 simulation cases and CMG STARS is used for simulation runs. By using least squares method, a linear correlation is found to calculate CO2 storage capacity of the deep saline carbonate aquifers with a correlation coefficient 0.81 by using variables found from literature and simulation results. Numerical dispersion effects have been considered by increasing the grid dimensions. It has been found that correlation coefficient decreased to 0.77 when the grid size was increased from 250 ft to 750 ft. The sensitivity analysis shows that the most important parameter that affects CO2 storage capacity is depth since the pressure difference between formation pressure and fracture pressure increases with depth. Also, CO2 storage mechanisms are investigated at the end of 300 years of simulation. Most of the gas (up to 90%) injected into formation dissolves into the formation water and negligible amount of CO2 reacts with carbonate. This result is consistent with sensitivity analysis results since the variables affecting the solubility of CO2 in brine have greater affect on storage capacity of aquifers. Dimensionless linear and nonlinear predictive models are constructed to estimate the CO2 storage capacity of all deep saline carbonate aquifers and it is found that the best dimensionless predictive model is linear one independent of bulk volume of the aquifer.
7

Cleaner Production Opportunity Assessment For Market Milk Production In Ataturk Orman Ciftligi (aoc) Facility

Ozbay, Arzu 01 December 2003 (has links) (PDF)
In this study, possible cleaner production opportunities for a dairy processing facility are examined, considering the market milk production process. Cleaner production concept and its key tools of implementation were analyzed to build the basis of study. General production process and its resulting environmental loads are discussed by taking possible CP opportunities as the axis of study. A methodology is developed for cleaner production opportunity assessment in Milk Processing Facility of Atat&uuml / rk Orman Ciftligi. The methodology covers two major steps / preparation of checklists for assisting auditing and opportunity assessment / implementation of the mass balance analysis. For mass balance analysis, measurements and experimental analysis of the mass flows are utilized to determine the inputs and outputs. Prepared check lists are utilized to determine waste reduction options that could be implemented. Selected opportunities are evaluated considering its environmental benefits and economic feasibility.
8

Utilization Of Waste Materials From Iron-steel And Zinc Industries For Sorption Of Hydrogen Sulfide At High Concentrations

Harmanci, Ebru 01 July 2004 (has links) (PDF)
The slags from iron-steel and zinc industries are rich in metal oxide contents like FeO, MnO, CaO. However, these slags are not used extensively, except some usage in the cement industry. These slags can be used in removing H2S from waste gases from different industrial sources. The purpose of this research is to study the effect of initial concentration of H2S on the capacity and sorbent efficiency of waste materials from iron-steel and zinc industries. Experiments were conducted in a 25 mm-quartz reactor with simulated gases containing H2S as reactive gas. Breakthrough curves for sulfidation reactions were obtained for 3000 ppmv, 4000 ppmv and 5000 ppmv initial H2S concentrations at the reaction temperature range of 500&deg / C&ndash / 700&deg / C. According to the results obtained from the experiments, the H2S removal capacity of both slags increased with increasing reaction temperature, however, the H2S removal capacity of the slags decreases as the initial H2S concentration increases. Cyclic sulfidation and regeneration tests were applied to both steel and zinc slags in order to determine the regenerability of the slags. In cyclic tests, zinc slag gave better results than steel slag. A &ldquo / Deactivation Model&rdquo / was used in order to fit the breakthrough curves obtained experimentally to the breakthrough curves predicted from the deactivation model. A very good fit was obtained for both steel and zinc slags. Zinc slag was shown to be more suitable for gas cleanup than steel slag taking into account its high H2S removal efficiency, regenerability and low cost (almost free of charge).
9

Assessment Of The Best Available Wastewater Management Techniques For A Textile Mill: Cost And Benefit Analysis

Dogan, Bugce 01 September 2008 (has links) (PDF)
The Integrated Pollution Prevention and Control (IPPC) Directive from the European Union strives to achieve a high level of environmental protection by preventing or reducing the pollution emanating from industrial installations directly at the source. The Directive implies that the emission limit values should be set in accordance with each industry&rsquo / s Best Available Techniques (BAT). In the present study, water recovery and wastewater treatability alternatives developed beforehand were evaluated towards the evaluation of BATs for the management of wastewaters from a denim textile mill. For this purpose, an assessment that translates the key environmental aspects into a quantitative measure of environmental performance and also financial analysis were performed for each of the alternatives. The alternatives considered for water recovery from dyeing wastewaters were nanofiltration (NF) with coagulation and/or microfiltration (MF) pretreatment, ozonation or peroxone and Fenton oxidation. On the other hand, for the end-of-pipe treatment of the mill&rsquo / s mixed wastewater / ozonation, Fenton oxidation, membrane bioreactor (MBR) and activated sludge process followed by membrane filtration technologies were evaluated. The results have indicated that membrane filtration process providing 70 % water recovery with the least environmental impacts is the BAT for water recovery. On the other side, MBR technology has appeared as the BAT for the end-of-pipe treatment of the mill&rsquo / s mixed wastewater. A technical and financial comparison of these two BAT alternatives revealed that water recovery via membrane filtration from dyeing wastewaters is selected as the BAT for the water and wastewater management in the mill.

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