Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 154-160). Also available via the Internet.

Thesis (Ph. D.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

The feasibility of the excess lime process for color removal from textile dye wastes was evaluated. The lime dosages were optimized by using anionic, cationic, and nonionic polyelectrolytes as coagulant aids. The effect of the process on the removal of organic pollutants was determined. The time interval between coagulant additions was analyzed. Color reductions of at least 94 per cent were obtained by the lime and lime-polyelectrolyte processes. The lime dosage of 980 to 1,060 ppm was decreased by at least 30 per cent using 5 ppm polyelectrolyte dosages. The processes reduced the Total Organic Carbon concentration by 73 per cent approximately, the Chemical Oxygen Demand by 50 per cent, and suspended solids by about 85 to 90 per cent. The excess lime process was more efficient in removing organic matter than the lime-polyelectrolyte processes, and also incurred the least chemical coagulant cost. The excess lime process was most effective at 30 minutes flocculation and 30 minutes settling. The lime-polyelectrolyte processes were more effective when the polyelectrolyte was added after about 30 minutes lime flocculation and settled for 5 minutes. The lime-polyelectrolyte processes produced a floe which settled rapidly. The volume of sludge produced was about 8.1 to 12.8 per cent, resulting in a sludge to supernatant ratio range of 1:7 to 1:11. The lime-polyelectrolyte sludge volumes were usually higher than the lime sludge volumes. / Master of Science

The compound p-(2-hydroxyethylsulfone) aniline was isolated from a reduced solution of a fiber-reactive azo dye. The identity and purity of this product was assessed through elemental composition analysis, high performance liquid chromatography (HPLC), gas chromatography/mass spectroscopy (GC/MS), and nuclear magnetic resonance spectroscopy (NMR). The toxicity of this purified compound was measured with Microtox and Daphnia pulex tests. Microtox tests were also performed on compounds with similar structures to p- (2-hydroxyethylsulfone) aniline. Wastewater samples containing textile dye wastes from a Publicly Owned Treatment Works (POTW) that treated textile dye wastes were monitored for the presence of p-(2-hydroxyethylsulfone) aniline using HPLC. Microtox testing was performed on these samples. Analytical tests confirmed the identity and purity of p-(2-hydroxyethylsulfone) aniline as the reduced product. Microtox tests revealed the concentration at which 50% of the light output was reduced (EC₅₀) after 5 minutes of exposure was 12.8 mg/L. Daphnia pulex testing yielded the concentration which was lethal to 50% of the tested organisms (LC₅₀) to be 113 mg/L. The 5-minute Microtox EC₅₀, values of aniline, sulfanilamide, 2-hydroxyethylsulfone, and 4-ethylaniline were 106.7, 8.15, >80, and 2.05 mg/L, respectively. The reduction product, p-(2-hydroxyethylsulfone)aniline, was not detected in textile-containing wastewater from the Martinsville POTW. The Microtox EC₅₀, for this wastewater, ranged from 6.05 to >75 mg/L. / Master of Science

The average Swede consumes 14 kilos of textiles every year and disposes of 10 kilos, of which 8 kilos end up in the household mixed waste. When disposed of in the household mixed waste, the textiles will be incinerated. Sweden has adopted the EU’s Extended Producer Responsibility policy as a national policy after which all Swedish provinces, as late as 2025, are obliged to collect and treat textile waste separately from other waste to make better use of it through processing for re- or downcycling instead of energy recovery through incineration. This puts waste management companies at risk of facing larger textiles waste masses than they may be able to handle. Hence, waste management companies must prepare for this imminent challenge by engaging the public, influencing them towards textile waste reduction. However, to engage (with) the public, these organizations must first learn about the citizens’ perceived knowledge, attitudes, and self-efficacy concerning textile waste reduction alongside the current barriers and enablers they experience regarding reducing consumption and correct disposal of textile waste. Qualitative data was gathered by employing a questionnaire and focus groups, and through thematic analysis, survey data from roughly 430 respondents and three focus groups were evaluated. Significant findings of this study were that citizens face substantial barriers such as lack of information and infrastructure, which leads them to resort to inappropriate disposal. While they are aware of their wrongdoings, they are, on the one hand, incapable of acting differently and, on the other hand, uninformed about waste prevention, generation, and disposal. However, they are open to education and collaboration with waste management companies. Furthermore, the study concludes that, while the individual has a significant role in implementing policies, a systems view must be employed not to overload the individual with responsibility.

<p>Biodegradation of untreated cotton, linen, and hemp textiles as three substrates – measured through biogas production – was studied to compare digestion yield and the ability of anaerobic sludge as inoculum to utilize the sugars in these textiles without pretreatment. Digestion of these textile substrates was carried out over a 26-day study, with daily sampling of biogas production, to measure biogas production rate and accumulation. The flasks were maintained at 37 °C and 150 RPM with a substrate to inoculum ratio (SIR) of 0.5 g sugars from substrate g-1 VSinoculum from anaerobic sludge. Biogas samples were analyzed through gas chromatography (GC) to determine general biogas composition produced by each textile. Biogas production was notable after the four-day mark; with first peaks occurring on day five (hemp, cellulose), day seven (cotton), and day nine (linen). Production of biogas in the control largely outperformed trials with no added substrate, but overall the methane fractions of the gas was lower than expected, indicating that pretreatment is likely necessary for more complete biodegradation of natural textiles. </p>

Submitted in fulfillment of the academic requirements for the Degree of Master of Technology: Biotechnology, Durban Institute of Technology, 2005. / The cumulative effects of pollution have led to increased public concern, which is resulting in strict legislation on the discharge of wastes in whatever state they are present, i.e. solid, liquid or gas. Currently, in South Africa, effluents with a high organic load are sent to landfills or marine outfall because the cost of discharge to sewer is prohibitive. In regions where there is a net surplus of rainfall, landfill sites have the potential to pollute the groundwater due to saturated soil conditions. Therefore, many landfill sites should not receive liquid effluents. If liquid wastes are disposed onto landfills, then an alternate sink is required for the treatment of the high volumes of leachate that are generated. These concentrated effluents could then be treated by biological, chemical or physical methods to reduce the pollution load in the natural water resources. In this study, anaerobic digestion has been identified as one of the biological processes that can be applied to treat high-strength or toxic organic liquid effluents, since a survey conducted by Sacks (1997) indicated that many anaerobic digesters in the KwaZulu-Natal region have spare capacity. However before high strength industrial wastes can be treated in existing anaerobic digesters, their impact on the digestion process, i.e. their toxicity and biodegradability under anaerobic conditions, needs to be determined. During this project, several high-strength or toxic industrial effluents were tested to assess their toxicity and biodegradability under anaerobic conditions. These include three synthetic textile size effluents from the textile industry (Textile effluent 1, 2, and 3) and three hazardous landfillieachates (Holfontein, Shongweni and Aloes). In addition, the components of a textile effluent, i.e., starch and wax, were tested to determine which / M

The application of anaerobic digestion technology is growing worldwide, mainly because of its environmental benefits. Nevertheless, anaerobic degradation is a rather slow and sensitive process. One of the reasons is the recalcitrance nature of certain fractions of the substrate (e.g., lignocelluloses) used for microbial degradation; thus, the hydrolysis becomes the rate-limiting step. The other reason is that the degradation of organic matter is based on a highly dynamic, multi-step process of physicochemical and biochemical reactions. The reactions take place in a sequential and parallel way under symbiotic interrelation of a variety of anaerobic microorganisms, which all together make the process sensitive. The first stage of the decomposition of the organic matter is performed by fast growing (hydrolytic and acid forming) microorganisms, while in the second stage the organic acids produced are metabolized by the slow growing methanogens, which are more sensitive than the acidogens; thus, methanogenesis becomes the rate-limiting step. The first part of this work evaluates the effects of a pretreatment using an organic solvent, N-methylmorpholine-N-oxide (NMMO), on cellulose-based materials in order to overcome the challenge of biomass recalcitrance and to increase the rate of the hydrolysis. NMMO-pretreatment of straw separated from the cattle and horse manure resulted in increased methane yields, by 53% and 51%, respectively, in batch digestion tests. The same kind of pretreatment of the forest residues led to an increase by 141% in the methane production during the following batch digestion assays. The second part of this work evaluates the efficacy of a two-stage process to overcome the second challenge with methanogenesis as the rate-limiting step, by using CSTR (continuous stirred tank reactors) and UASB (up flow anaerobic sludge blanket) on a wide variety of different waste fractions in order to decrease the time needed for the digestion process. In the two-stage semi-continuous process, the NMMO-pretreatment of jeans increased the biogas yield due to a more efficient hydrolysis compared to that of the untreated jeans. The results indicated that a higher organic loading rate (OLR) and a lower retention time could be achieved if the material was easily degradable. Comparing the two-stage and the single-stage process, treating the municipal solid waste (MSW) and waste from several food processing industries (FPW), showed that the OLR could be increased from 2 gVS/l/d to 10 gVS/l /d, and at the same time the HRT could be decreased from 10 to 3 days, which is a significant improvement that could be beneficial from an industrial point of view. The conventional single stage, on the other hand, could only handle an OLR of 3 gVS/l/d and HRT of 7 days.

Syftet med rapporten var att studera möjliga återvinningstekniker för Ragn-Sells. För detta användes litteratursökning och intervjuer. Återvinningstekniker som studerats är mekanisk bearbetning, mekanisk återvinning, kemisk återvinning och viskostillverkning. Flera underklasser till dessa metoder studerades också, liksom flera sätt att tillverka återvunna produkter. Rapporten nämner ett urval av återvinningstekniker och försöker inte nämna alla tillgängliga återvinningstekniker.Återvinningsteknikerna har sorterats enligt prioriteringen i EU:s återvinningsdirektiv (2008/98/EG). Alla utom en teknik var genomförbar enligt den kunskap och teknologi som existerar idag. Fyra återvinningstekniker är inte lagliga i EU.En stor majoritet av återvinningsmetoderna är tekniskt genomförbara idag. Uppgifter saknas om det är tekniskt möjligt att tillverka viskos av återvunna textila fibrer. Återvinningsmetoder som berör att gräva ned textila fibrer från konsument i marken är inte tillåtna enligt EU-lagstiftning. The recycling techniques studied were mechanical processing, mechanical recycling, chemical recycling and regenerated fiber spinning. There were several subclasses to these recycling methods, and several ways of making recycled products. The study mentions a selection of recycling techniques and does not intent to mention all available techniques. Technical ways of recycling textile have been studied by literature review and interviews. The recycling methods have been sorted by the priority list in EU Directive on Waste (2008/98/EG). All but one method was feasible with the knowledge and technology available today. All but four recycling methods are legal in Europe.A great majority of the recycling techniques were found feasible with the technology and knowledge available today. Data has not been found in the case of using recycled fibers as raw material for making regenerated fibers. Recycling techniques which interfere with burying recycled fibers from consumer applications in the ground were found illegal in the European Union. / Program: Textilingenjörsutbildningen

Idag produceras 70 miljoner årston textilfibrer. Denna siffra kommer fram tills år 2050 att mer än tredubblas i takt med att jordens befolkning och medelinkomsten per person ökar. År 2013 förbrukade svenskarna så mycket som 12,5 kilo textil per person varav 8 kilo slängdes i hushållssoporna. Textilindustrin ställs inför stora utmaningar, dels att tillgodose ett större behov av fibrer samt att hantera ett växande avfallsberg. Det behövs därför återvinningsmetoder för att ta tillvara på textiler både från industrier och konsumenter. Företaget Re:newcell finansierar forskning på Kungliga Tekniska Högskolan, KTH, i Stockholm. Denna forskning undersöker möjligheten att återvinna cellulosabaserat textilavfall till en dissolvingmassa. Massan kan användas för att spinna nya cellulosabaserade konstfibrer. I detta examensarbete undersöks egenskaperna hos lyocellfibrer framställda av dissolvingmassa från Re:newcell. Dissolvingmassan för dessa fibrer har producerats av secondhandjeans. Fibrerna jämförs genom projektet med konventionellt framställda lyocellfibrer, Tencel®. På Textilhögskolan har ett ringspunnet garn producerats av respektive fiber. Garnernas linjära densitet har kontrollerats för att uppnå samma grovlek som ett kommersiellt producerat Tencel®garn. Dragprovning av samtliga tre garner har utförts för att bestämma tenacitet samt brottstöjning. En slätstickad trikåkvalitet har sedan tillverkats av respektive garn. På dessa tre trikåkvaliteter har ett antal tester utförts för att kunna bestämma kvadratmetervikt, dimensionsändring efter tvätt, fuktlednings-, absorptions- och färgupptagningsförmåga, anfärgning till andra material, färghärdighet efter konsumentvätt, nöthärdighet samt matrialens tendens att noppra. Syftet med arbetet är att kunna dra slutsatser om huruvida Re:newcellfibern kan komplettera konventionellt producerade cellulosabaserade konstfibrer för tillverkning av nya klädesplagg. Slutsatsen är att Re:newcellfibrerna kan spinnas till ett garn med samma linjära densitet som ett kommersiellt framställt Tencel®garn. Re:newcellgarnet har en god styrka och töjs i liten utstäckning i både torrt och vått tillstånd. Av garnet är det möjligt att tillverka en rundstickad vara av slätstickad kvalitet. Efter testerna kan det konstateras att detta material krymper accepterbart vid konsumenttvätt. Det kan bäras nära kroppen eftersom absorptions- och fuktledningsförmågan är god. Färgupptagningsförmågan är god för reaktivfärg av antrakinon typ. En del av färgen tvättas av men materialet anfärgar inte andra material märkbart. Re:newcelltrikån står emot förhållandevis hög nötning mot en standardiserad ullväv. Materialet noppras i stor utsträckning rätsida mot rätsida men nopprorna slits av efter hand. Testerna som har utförts på materialen visar att Re:newcellfibern har utmärkta egenskaper för att kunna användas i ett plagg som till exempel en t-shirt. Därmed har dissolvingmassan från Re:newcell en stor potential att vara en ny råvara i produktionen av cellulosabaserade konstfibrer. Dissolvingmassan kan bidra till att textilindustrin kan ta tillvara sitt avfall och även tillgodose en del av det växande behovet av textilfibrer i framtiden. / The population of the earth, as well as the average income, are both on the increase. Therefore the already high consumption of textiles in the world is expected to be even greater in the future. At present, 70 million tonnes of textile fibres are being produced yearly. This figure could rise to as much as 240 million within the next 35 years. In Sweden alone, the people were consuming around 12.5 kilos of textiles per person in 2010. About 8 of these kilos were discarded as garbage. The textile industry is facing big challenges, both in finding new resources for production of fibres as well as dealing with the issue of large amounts of textile waste from consumers and companies. Re:newcell is a Swedish company financing research at Royal Institute of Technology, KTH, in Stockholm. Their researchers are investigating the possibility to recycle cotton and other cellulosic textile materials in order to produce dissolved pulp. Thereafter cellulosic man-made fibres are being produced from the pulp. The properties of lyocell fibres produced from the dissolved pulp from Re:newcell is being investigated in this Bachelor thesis. The dissolved pulp has been produced from jeans bought in second-hand shops. These fibres are being compared to the conventionally produced lyocell fibres, Tencel®. A ring spun yarn of each fibre type has been produced at the Swedish School of Textiles. The linear density of the yarns have been determined in order to achieve the same thickness of the yarn as a commercially spun yarn also made from Tencel® fibres. A test of tensile strength and elongation has been carried out on each of the three yarns. Thereafter the yarns have been used to manufacture a knitted fabric on a circular knitting machine. Each of the knitted fabrics have gone through a series of tests regarding weight of fabric per square meter, dimensional change after washing, wicking and absorbency properties, dye exhaustion, colour staining to other materials during laundering and colour change after laundering, abrasion resistance and tendency to create fuzzing and pills. The purpose of the study is to make conclusions about whether this fibre has the potential to complement other cellulosic man-made fibres. The conclusion is that Re:newcell fibres can be used to spin a yarn with the linear density of 25 tex. This yarn can be utilized to produce a circular knitted fabric light enough to make T-shirts. After the testing it is concluded that the shrinking percentage after consumer’s washing is acceptable. In addition, the material could be worn close to the body because of the good absorbency and wicking properties. The exhaustion of dyestuff of antrakinon type from the dyeing liquor is equally very good. Although some of the dyestuff is being washed in laundering, the Re:newcell tricot is not staining other materials noticeably. The Re:newcell material can also withstand high abrasion against a woven wool material. The tendency to form fuzzing and pills is great but the pills are being torn of eventually. It may be concluded that the fibres, made by the dissolved pulp of Re:newcell in the lyocell process, can be used to manufacture a yarn with better strength than two investigated yarns of Tencel®. The tests carried out on the fabrics produced in the project show that the Re:newcell fibre has excellent properties in order to function as a material in a garment, for example a T-shirt. Therefore the dissolved pulp of Re:newcell has the possibility to be a new raw material in the production of man-made cellulosic fibres. This enables the textile industry to deal with their excess waste, and to meet the increasing demand for fibres in the world.