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Development and practical application of unhairing method without using sulfideTakase, Kazuya, Terashima, M., Yoshimura, K. 24 June 2019 (has links)
Content:
Leather manufacturing industry uses a lot of water and chemicals, and it discharges large amounts of wastewater. The processing a large amounts of wastewater requires a huge cost. Therefore, reduction of amount of a pollution load in wastewater is a theme in many countries around the world. During the leather process, a lot of pollutants occur in the unhairing process. Some estimate that the amount of pollution generated in the unhairing process accounts for 70% of the entire leather manufacturing process. In this unhairing process, usually a large amount of sulfide is used. Sulfide is known to generate hydrogen sulfide and cause damage to the drain pipe. In Tokyo, strict criteria are set for draining sulfide to sewers. Therefore, reducing the amount of sulfide used is an important task for tanner. In addition, since sulfide has no degreasing effect, a large amount of surfactant is required in the unhairing process. However, to reduce the cost and the load of the wastewater, it is also required to reduce the amount of the surfactant used. Furthermore, in recent years, the types of usable surfactants have also been limited. Therefore, development of a method of effectively removing hair loss and degreasing without using a sulfide is urgent for the leather manufacturing industry.
On the other hand, pelts are widely used as raw materials for foods such as gelatin and collagen casing, cosmetics, and pharmaceuticals. However, sulfides are not originally recognized as food additives. Therefore, some companies are concerned about using pelts as a raw material for food using sulfide in the unhairing process. Also from this point of view, it is necessary to develop an unhairing method without using sulfides.
The method using sodium hydroxide has been studied for a long time. However, this method is hard in handling, and is difficult to set conditions such as concentration and temperature. That is, while successful at the experimental level, it has not been put to practical use. Therefore, we studied a method to solve the above problem using sodium hydroxide.
The method developed this time can reduce the pollutant in waste water, and the amount of water used in the unhairing process to 1/10 or less of the conventional one. Moreover, since it is not influenced by water temperature, it made it possible to stably remove hair irrespective of the season. The finished leather kept sufficient strength. In addition, sodium hydroxide reacts with fat in the skin and turns it into soap, so it shows the degreasing effect and contributes to reduce the dosage of degreasing agent.
Take-Away:
development of unhairing method without using sulfide
contributes to reduce the dosage of degreasing agent
reduce the pollutant in waste water
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Effects of Whey Protein Concentrate, Phosphate, and Sodium Hydroxide on Texture and Acceptability of Turkey and Beef RollsMoiseev, Igor V. 01 May 1994 (has links)
Processed turkey rolls were prepared with 1 or 3% whey protein concentrates WPC-50 (pH=5.80), WPC-60 (pH=4.53) and WPC-75 (pH=6.85} containing 50, 60 and 75% protein along with controls (phosphate and no phosphate). Control rolls made with 0.5% phosphate had the highest bind strength, and sensory evaluation scores. Only WPC-75 (1%) was acceptable as a binding agent and flavor enhancer. WPC-60 reduced pink discoloration of rolls, but flavor, bind and cohesiveness scores were unacceptably low. WPC-50 was not an effective binding agent. In general, rolls made with 3% WPC had lower scores for intensity of turkey flavor.
Bind strength and sensory characteristics were compared for restructured beef rolls formulated with 1% salt, 0.375% sodium tripolyphosphate (STPP) or O. 07 % sodium hydroxide (NaOH), and 5, 10 or 20% added water. Controls also had 1% salt, but no STPP or NaOH. Relative bind strength of rolls was STPP > NaOH > controls. Addition of 20% water reduced bind strength. Cooked yield, moisture content, beef flavor and texture of NaOH rolls were similar to STPP rolls. Bind strength and cohesiveness of NaOH rolls were lower than STPP rolls, but still acceptable.
For measuring bind strength of turkey and beef rolls, a sensitive and inexpensive penetrometer was developed. It was equipped with a top-loading balance, accessories, IBM-compatible personal computer and Quick-Basic program that allowed continuously collected penetration force data . at specific time intervals. Penetrometer bind strength and taste panel cohesiveness of turkey and beef rolls were highly correlated (r=0.89 and r=0.93, respectively).
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MECHANICALLY STRONG/ LOW FLAMMABILITY POLY (VINYL ALCOHOL) AEROGELSCheng, Zhihan 23 May 2019 (has links)
No description available.
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A study on the thermal stability of sodium dithionite using ATR-FTIR spectroscopy / A study on the thermal stability of sodium dithionite using ATR-FTIR spectroscopyVegunta, Vijaya Lakshmi January 2016 (has links)
Sodium dithionite (Na2S2O4) is a powerful reducing agent. It has therefore been suggested to be used as an additive in kraft pulping to improve the yield. However, sodium dithionite easily decomposes and it is thus important to determine the effect of different conditions. The aim of this thesis has been to investigate the thermal stability of sodium dithionite under anaerobic conditions using ATR-FTIR spectroscopy under different conditions, such as heating temperature, concentration of the solution, heating time and pH. The stability of sodium dithionite was found to decrease with increasing heating temperature, concentration of sodium dithionite, heating time and pH. Sodium dithionite was found to be relatively stable at moderate alkaline pH:s 11.5 and 12.5, while a rapid decrease in stability with time was noted at higher heating temperatures and concentrations of sodium dithionite. Based on this study on the thermal stability of sodium dithionite, the following conditions are suggested as the most promising, when adding sodium dithionite to the kraft cooking as an additive; pH 12.5, with 0.4 M concentration of the solution, at a heating temperature of 100 °C.
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Effects of Fly Ash on the properties of Alkali Activated Slag ConcreteKothari, Ankit January 2017 (has links)
This master thesis presents the effects of fly ash on the properties of alkali activated slag concrete, commonly referred as Geopolymer concrete (GPC). Cement manufacturer are major producers of CO2 which negatively affects the environment. Due to the increased construction activities and environmental concern, it is necessary to introduce alternative and eco-friendly binders for concrete. Slag and fly ash based concrete, which is by-product from industrial waste, is probably the best replacement for OPC concrete due to less or nil environmental issue. Most of the researchers have already concluded that slag and fly ash can be used as binders in concrete by activating them with alkali activator solution (e.g. by sodium silicate or sodium carbonate). In the present work concretes were produced by varying the proportion of slag to fly ash (40:60, 50:50, 60:40 & 80:20); amount of alkali activators (5, 10 & 14) and chemical modulus of sodium silicate (Ms) (0.25, 0.5 & 1). Setting times and compressive strength values were evaluated. Results showed that decrease in fly ash content irrespective of % of alkali activators and alkali modulus (Ms), the compressive strength was increasing and setting time was getting shorter. The produced concretes showed increasing compressive strength with increase in % of alkali activator for Ms 0.5 and 1, while for Ms=0.25 the strength was decreasing with increase in % of alkali activators. From this it can be concluded that, Ms=0.5 was the optimum point below which the reaction got slower. Based on the initial investigations, mix S8:F2-SS10(1) and S8:F2-SS10(0.5) showed most promising results in terms of fresh and hardened concrete properties and were easy to handle. Consequently, the above mentioned mixture was chosen to be studied in more detail. The experimental program for these mixes included determination of slump flow, compressive strength (7, 14, 28 days) and shrinkage (drying and autogenous). The results shows that, strength increased with time and comparatively mix with Ms=0.5 showed higher compressive strength than mix with Ms=1, due to higher alkalinity of the pore solution. Mix with Ms=1 showed higher drying shrinkage compared to mix with Ms=0.5, which was explained by higher alkalinity of the solutions (Ms=0.5) leading to rapid formation of aluminosilicate gel. Autogenous shrinkage appeared to be higher for mix with Ms=0.5. This was associated with lower modulus which leads to densification of concrete microstructure at early ages. Pore diameter decrease and the water trapped in the pores exerted increasing tensile stress resulting for higher autogenous shrinkage.
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SÍNTESE E CARACTERIZAÇÃO DE ESPUMAS VÍTREAS CONTENDO TiO2 E UTILIZANDO HIDRÓXIDO DE SÓDIO COMO AGENTE ESPUMANTEBento, André César 10 April 2012 (has links)
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Previous issue date: 2012-04-10 / In this work, the effect of sodium hydroxide as a glass foaming agent using glass waste in the foam formulation was performed. During the synthesis process, the variation of temperature, heating rate and sintering time was investigated. Sample density and average pore sizes were estimated using mercury porosimetry. The morphology of the glass foams were evaluated using scanning electron microscopy, phase formation was studied using X-ray diffraction, and chemical composition was estimated using X-ray fluorescence. As a result, glass foam with hierarchical density. / Neste trabalho foi realizado um estudo sobre a ação do hidróxido de sódio como agente formador de espuma vítrea usando resíduos de vidro em sua composição. Para a síntese, investigou-se a variação da temperatura, da taxa de aquecimento e do tempo de sinterização. Utilizando-se a técnica de porosimetria de mercúrio, para estimar a densidade e o tamanho médio de poros. A morfologia das espumas vítreas foi avaliada através da microscopia eletrônica de varredura de alta resolução (FEG) e as fases das espumas vítreas foram caracterizadas pelas técnicas de difração de raios X e a composição química estimada usando fluorescência de raios X.
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Mercerization and Enzymatic Pretreatment of Cellulose in Dissolving PulpsAlmlöf Ambjörnsson, Heléne January 2013 (has links)
This thesis deals with the preparation of chemically and/or enzymatically modified cellulose. This modification can be either irreversible or reversible. Irreversible modification is used to prepare cellulose derivatives as end products, whereas reversible modification is used to enhance solubility in the preparation of regenerated cellulose. The irreversible modification studied here was the preparation of carboxymethyl cellulose (CMC) using extended mercerization of a spruce dissolving pulp. More specifically the parameters studied were the effect of mercerization at different proportions of cellulose I and II in the dissolving pulp, the concentration of alkali, the temperature and the reaction time. The parameters evaluated were the degree of substitution, the filterability and the amount of gel obtained when the resulting CMC was dissolved in water. Molecular structures of CMC and its gel fractions were analysed by using NIR FT Raman spectroscopy. It was found that the alkali concentration in the mercerization stage had an extensive influence on the subsequent etherification reaction. FT Raman spectra of CMC samples and their gel fractions prepared with low NaOH concentrations (9%) in the mercerization stage indicated an incomplete transformation of cellulose to Na-cellulose before carboxymethylation to CMC. Low average DS values of the CMC, i.e. between 0.42 and 0.50 were obtained. Such CMC dissolved in water resulted in very thick and semi solid gum-like gels, probably due to an uneven distribution of substituents along the cellulose backbone. FT Raman spectra of CMC samples and their gel fractions mercerized at higher alkaline concentration, i.e. 18.25 and 27.5% in the mercerization stage, indicated on the other hand a complete transformation of cellulose to Na-cellulose before carboxymethylation to CMC. Higher average DS values of the CMC, i.e. between 0.88 and 1.05 were therefore obtained. When dissolved in water such CMC caused gel formation especially when prepared from dissolving pulp with a high fraction of cellulose II. The reversible modification studied was the dissolution of cellulose in NaOH/ZnO. Here the effect of enzyme pretreatment was investigated by using two mono-component enzymes; namely xylanase and endoglucanase, used in consecutive stages. It was found that although the crystallinity and the specific surface area of the dissolving pulp sustained minimal change during the enzymatic treatment; the solubility of pulp increased in a NaOH/ZnO solution from 29% for untreated pulp up to 81% for enzymatic pretreated pulp. / Baksidetext Cellulose can be chemically and/or enzymatically modified. Irreversible modification is used to prepare cellulose derivatives as end products, reversible modification to enhance solubility in the preparation of regenerated cellulose. The irreversible modification studied here was the preparation of carboxymethyl cellulose (CMC) using extended mercerization of a spruce dissolving pulp. More specifically the parameters studied were the effect of mercerization at different proportions of cellulose I and II in the dissolving pulp, the concentration of alkali, the temperature and the reaction time. It was found that the alkali concentration in the mercerization stage had an extensive influence on the subsequent etherification reaction. The content of cellulose II had little effect on degree of substitution (DS) at low NaOH concentration, but tended to decrease DS at higher NaOH concentration in both cases compared with cellulose I. It was also found that the content of cellulose II correlates with the gel formation obtained when the CMC is dissolved in water. The reversible modification studied was the dissolution of cellulose in NaOH/ZnO. Here the effect of enzyme pretreatment was investigated by using two mono-component enzymes; namely xylanase and endoglucanase, used in consecutive stages. It was found that the solubility of pulp increased in a NaOH/ZnO solution from 29% for untreated pulp up to 81% for enzymatic pretreated pulp.
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Minimização de afluentes e avaliação de sistema biológico de tratamento de águas residuárias em uma indústria de conservas vegetais / Effluent minimization and evaluation of wastewater biologic system treatment in a vegetable-cannery industryHuber, Charles Soares 10 December 2007 (has links)
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Previous issue date: 2007-12-10 / The addition a chemical surfactant in the sodium hydroxide solution was evaluated in
the peach peeling process. The results were compared to the traditional process,
without chemical addition. It could be observed reduction from 57.14% in the sodium
hydroxide consumption, 49.18% in wastewater generation of the fruit washing
process and 42.81%, 16.02%, 45.45%, 24.16% and 31.82%, in the loads of chemical
oxygen demand (COD), biochemical oxygen demand (BOD), total Kjeldahl nitrogen
(TKN), total suspended solids (TSS) and the settleable solids (SS), respectively. The
fruit-cannery wastewaters must be treated. There are several processes that can be
used for the removal of materials and chemicals that can degrade the environment.
An upflow anaerobic sludge blanket (UASB) of a cannery industry (fruits and
vegetables) was evaluated. The system was assessed for 712 days and the
efficiency of total DQO removal was evaluated. The start-up began with a mean
organic loading rate (OLR) of 0.40kgDQO.m-3.d-1, and achieved a maximum OLR of
5.29kgDQO.m-3.d-1 in 307 days. The mean removal of total DQO was 86.87%. This
study showed that even with the seasonality of production, the UASB reactor is a
good alternative for the secondary treatment of fruit-cannery industry / Avaliou-se a adição de um surfactante químico à solução de hidróxido de sódio,
utilizada no processo de descasque químico do pêssego. Os resultados obtidos
foram comparados com o do processo tradicional, sem a adição desta substância.
Observou-se reduções de 57,14% no consumo de hidróxido de sódio, 49,18% na
geração de efluente líquido, no processo de lavagem da fruta e 42,81%, 16,02 %,
45,45%, 24,16% e 31,82%, nas cargas da demanda química de oxigênio (DQO),
demanda bioquímica de oxigênio (DBO), nitrogênio total Kjeldahl (NTK), sólidos
suspensos totais (SST) e dos sólidos sedimentáveis (SS), respectivamente. As
águas residuárias originadas no processo de industrialização da fruta devem ser
tratadas em uma estação de tratamento de efluentes. Existem diversos processos
que podem ser utilizados para a remoção dos materiais e substâncias
potencialmente prejudiciais ao meio ambiente. Monitorou-se a partida e a operação
de um reator anaeróbio de fluxo ascendente (UASB) tratando efluentes de uma
indústria de conservas de frutas e vegetais. O sistema foi monitorado por 712 dias e
avaliou-se a eficiência da remoção de demanda química de oxigênio (DQO) total. O
início da operação do reator foi com uma carga orgânica volumétrica (COV) aplicada
de 0,40kgDQO.m-3.d-1, atingindo-se uma COV máxima de 5,29kgDQO.m-3.d-1 em
307 dias. A remoção de DQO total foi de 86,87%. Este estudo mostrou que mesmo
com a sazonalidade de produção, os reatores UASB são uma boa alternativa de
tratamento secundário para a indústria conserveira
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Efeito dos tratamentos alcalino, ácido e oxidativo nas propriedades de amido de milho / Effect of alkali, acid and oxidative treatments on the properties of corn starchSpier, Franciela 30 March 2010 (has links)
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Previous issue date: 2010-03-30 / The starch market has been growing and improving, leading to search for products with
unique functional properties that industry requirements. The use of native starches is
limited, depending on the processing conditions such as temperature, pH, pressure
restricting its application in industrial scale. The production of modified starch is an
alternative that has been in development for some time in order to overcome one or more
limitations of native starches, increasing its use in industry. The objective of this research
was to evaluate the properties of corn starch chemically modified, alone or combined
action by the acid, oxidative and alkaline. The corn starch granules were treated with a
solution of sodium hydroxide at concentrations of 0.09% and 0.18%, with lactic acid
solution, 2% and 4%, and a solution of sodium hypochlorite 1% and 2%. Later were
neutralized, washed, dried, ground and stored. The starches were evaluated for amylose
content, content of carbonyl and carboxyl, paste properties, diffraction of X-ray, swelling
power and solubility and enzymatic susceptibility. The corn starch oxidized with sodium
hypochlorite (2%) showed a reduction in levels of amylose and treated with alkali and acid
increased. The oxidative treatment increased gradually, the levels of carbonyl and
carboxyl with increasing concentration of sodium hypochlorite. Among the treatments
studied the oxidative treatment was more interference in the pasting properties of starch
increased the maximum viscosity and breakdown and reduce the pasting temperature and
final viscosity. The interaction between the alkaline and acid treatments affected the
crystallinity of maize starch. The oxidative treatment increased the solubility of corn starch
at all temperatures examined, especially in the incubation temperatures are higher than
the highest concentration (2%), significantly increased the rate of hydrolysis / O mercado de amidos vem crescendo e se aperfeiçoando, levando à busca de
produtos com características específicas que atendam às exigências da indústria. A
utilização de amidos nativos é limitado, em função das condições de processamento
como temperatura, pH e pressão que restringem sua aplicação em escala industrial. A
produção de amidos modificados é uma alternativa que vem sendo desenvolvida há
algum tempo com o objetivo de superar uma ou mais limitações dos amidos nativos,
aumentando sua utilização na indústria. O objetivo do trabalho foi avaliar as propriedades
de amido de milho modificado quimicamente, de forma isolada ou combinada, pela ação
alcalina, ácida e oxidativa. Os amidos de milho foram tratados com solução de hidróxido
de sódio nas concentrações de 0,09% e 0,18%, com solução de ácido lático, 2% e 4%, e
com solução de hipoclorito de sódio 1% e 2%. Posteriormente foram neutralizados,
lavados, secos, moídos e armazenados. Os amidos foram avaliados quanto ao teor de
amilose, teor de carbonila e carboxila, propriedades de pasta, difração de raio-X, poder de
inchamento e solubilidade e suscetibilidade enzimática. Os amidos de milho oxidados com
hipoclorito de sódio (2%) apresentaram uma redução nos teores de amilose e os tratados
com álcali e ácido um acréscimo. O tratamento oxidativo aumentou os teores de carbonila
e carboxila com o aumento da concentração de hipoclorito de sódio. Dentre os
tratamentos estudados o oxidativo foi o que interferiu mais nas propriedades de pasta do
amido, aumentando a viscosidade máxima e a quebra, além de reduzir a temperatura de
pasta e a viscosidade final. A interação entre os tratamentos alcalino e ácido aumentou a
cristalinidade relativa do amido de milho. O tratamento oxidativo aumentou a solubilidade
do amido de milho em todas as temperaturas analisadas, principalmente nas
temperaturas de incubação mais elevadas, sendo que na maior concentração (2%),
aumentou significativamente a taxa de hidrólise.
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Ersättning av kalciumhydroxidtill natriumhydroxid vidbehandling av processvatten frånbetningsprocess : För effektivisering av befintlig vattenreningsprocess / Replacement of calcium hydroxide dosage to sodium hydroxide in thetreatment of residual water from pickling process : To increase the efficiency of an existing water purification processPålsson, Oskar January 2022 (has links)
Arbetet studerade skillnaderna mellan en användning av kalciumhydroxid samtnatriumhydroxid som pH-reglerande kemikalie i en kemisk vattenreningsanläggning.Samt dess påverkan på filtreringssteg som sandfilter, aktivkol filtrering samt jonbytarfiltrering. Det behandlade hur reningsgraden påverkas sett till metallreduktion av;krom, nickel, koppar och zink. Hur slammängderna är i förhållande tillvarandramellan de olika pH-reglernade kemikalierna och slutligen hur filtreringsstegenpåverkas beroende på vilken pH-reglerande kemikalie som doserats. Resultatet förarbetet har visat på att reningsgraden minskar vid användning av natriumhydroxidsom pH-reglerande kemikalie vilket besvarar en del av syftet samt frågeställningenmed arbetet. Ytterligare har resultatet påvisat att de efterkommande filtreringsstegensom i en eventuell framtid kan implementeras leder till en reducering avmetallhalterna i vattnet, vanligen gick reduceringen inte att statistiskt säkerställa mentendenser på en reducering påvisades. Även de erhållna slammängdernareducerades vid användning av natriumhydroxid som pH-reglerande kemikalie vilketvar ett förväntat resultat sett till hypotes och litteratur. Ytterligare minskadeturbiditeten för klarfasproverna vid en natriumhydroxiddosering i förhållande till enkalciumhydroxiddosering. Arbetets resultat har således påvisat den goda möjlighetenatt ersätta den manuella doseringen av solid kalciumhydroxid som pH-reglerandekemikalie emot en automatisk dosering av natriumhydroxid erhållen i vätskeform. / This work studied the differences between the use of calcium hydroxide and sodiumhydroxide as a pH-regulating chemical in a chemical water treatment plant. As wellas its impact on filtration steps such as sand filter, activated carbon filtration and ionexchange filtration. It dealt with how the degree of purification is affected in terms ofmetal reduction of; chromium, nickel, copper and zinc. How the sludge amounts arein relation to each other between the different pH-regulated chemicals and finallyhow the filtration steps are affected depending on which pH-regulating chemical hasbeen dosed. The results for the work have shown that the degree of purificationdecreases when using sodium hydroxide as a pH-regulating chemical, whichanswers part of the purpose and the question of the work. Furthermore, the resultshave shown that the subsequent filtration steps that can be implemented in thepossible future lead to a reduction of the metal contents in the water, usually thereduction could not be statistically confirmed but tendencies of a reduction wereshown. The amounts of sludge obtained were also reduced by using sodiumhydroxide as a pH-regulating chemical, which was an expected result in terms ofhypothesis and literature. Furthermore, the turbidity of the clear phase samplesdecreased at a sodium hydroxide dosage relative to a calcium hydroxide dosage.The results of the work have thus demonstrated the good possibility of replacing themanual dosing of solid calcium hydroxide as a pH-regulating chemical with anautomatic dosing of sodium hydroxide obtained in liquid form.
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