http://ir.bdu.edu.et/handle/123456789/2148 2001-01-13T08:24:38Z http://ir.bdu.edu.et/handle/123456789/9396 REUSING OF PRETREATMENT BATH IN BAHIR DAR TEXTILE SHARE COMPANY Textile industries are doing on to minimize their production costs by using sustainable technologies and by inventing new methods. Pretreatment is the heart of textile production. Bahir Dar Textile Share Company is using combined pretreatment process with exhaust and semi-continuous method. After the treatment is over, the residual chemicals are drained out into effluent treatment plant. The purpose of this project is to reuse the residual chemicals by replenishing the measured amounts of chemicals again for combined pretreatment process. The concentration of main chemicals, after pretreatment, before draining was analyzed. In case of jigger pretreatment process, the liquor is drain out after six ends with chemicals, then the main chemical concentrations (H2O2 and NaOH) was checked at this stage. In case of pad roll bleaching, the fabric rotates in the steaming chamber six up to twelve hours and washed with counter current washing machine. The chemicals are analyzed after washing is over. Based on the chemical analysis results, by replenishing with measured amounts of chemicals, pretreatment is done in both laboratory scales up to four times without changing water and on the bulk production; it has been done by mixing used water and fresh water. The effectiveness of pretreatment was evaluated in terms of absorbency; whiteness and the effect in subsequent dyeing parameters are checked. The dyeing and printing performance is also evaluated by doing dyeing and printing after each pretreatment is over. Acceptable results are found which can fulfill the products of the factory. Finally the amount of cost saved by fabric pretreatment, raw water and waste water treatment chemicals is calculated and also the amount of water which can be saved is shown. 2019-03-28T00:00:00Z http://ir.bdu.edu.et/handle/123456789/9395 USE OF MORINGA SEED (M. STENOPETALA) EXTRACT FOR REMOVAL OF DIRECT AND REACTIVE DYES IN TEXTILE WASTEWATER In this present work, the ability of Moringa seed extract–among other natural coagulants–to remove different types of dyes has been researched. Moringa stenopetala seed has been demonstrated to have high removal ability for anionic dyes. Because, textile wastewater is one of the most sources of pollution. This wastewater containing higher value of color, BOD, COD and several pollutants. If being directly discharged without treatment, it will bring serious problem to the ecological environment. Now days, the numbers of textile industries are increasing which threat the environment so the main finding of this work is to reduce the impact of wastewater. This study is particularly focused on testing the removal of dye wastewaters such as reactive dyes, direct dyes, mixture of dye wastes and mixture of industrial and dye wastewaters. The seeds of the Moringa tree contain a coagulant protein that can be used in the treatment of industrial wastewater. Therefore, the purpose of this study was to evaluate the effectiveness of Moringa seed as a coagulant for textile wastewater treatment. The effect of some operating parameters on coagulation namely pH, coagulant dose, mixing time, color removal and turbidity should be studied. From the results it was observed that the color removals in direct red and reactive red dyes are 94.45 and 98.4% respectively in simple extract. These dyes itself have highest value of color removal in saline extract about 96.6 and 97.3% respectively. These values of color removal of dyes are optimized at 70ml/L of coagulant and pH 10. Finally the mixture of industrial wastewater and dye wastes color removal and turbidity removal capacity is 85.8% in simple extract and 53% in saline extract respectively at optimized point. 2019-03-28T00:00:00Z http://ir.bdu.edu.et/handle/123456789/9394 INFLUENCE OF WATER HARDNESS ON BOILER EFFICIENCY IN BAHIR DAR TEXTILE SHARE COMPANY (BDTSC) Steam is one of important energy form highly required in textile industry for several textile processing. In Ethiopia there are several vertically arranged complex textile mills. Bahir Dar Textile Share Company (BDTSC) which is situated in Bahir Dar City, Capital of Amhara National Regional State is one of them. BDTSC uses electrical boiler for its steam generation. The steam produced by boiler has been used for sizing, pretreatment (desizing, scouring and bleaching), dyeing and finishing process operations. For efficient steam production electrical boiler has been fed with fine and soft water. The BDTSC water softening treatment line effectiveness was analyzed from the source (River Abay) to final line (zeolite) treatment unit as per water quality required for steam generation by boiler. Each water treatment arrangement, progressively gives improved water quality. However, overall treated water quality is not to level of required standard quality for steam generation in boiler, and in particular it contains large amount of hardness and total suspended solids which are beyond the acceptable limit for boiler water quality. As a result scale and sludge were formed in interior parts of the boiler and the boiler efficiency was decreased to 35%.Therefore, the water treatment line of BDTSC was optimized for achieving; water quality required for boiler use. Optimization activities were performed for each treatment unit arrangement considering specific optimization parameters for each treatment unit arrangement. With optimized treatment unit’s arrangement, the water quality required for boiler was significantly improved and as a consequence the calculated boiler efficiency increased from 35% to 66.3%. As per the record obtained from BDTSC, with previous water treatment arrangement, 8 mm thick scale is formed within three months interval, while with optimized water treatment units arrangement it is expected only 3mm thick scale will be formed within similar period of time interval. 2019-03-28T00:00:00Z http://ir.bdu.edu.et/handle/123456789/9362 ECOFRIENDLY VAT DYEING ON COTTON FABRICS AT BAHIR DAR TEXTILE SHARE COMPANY. For dyeing the cotton fabric with vat dyes, first it is required to reduce the dye using reducing agents. The reduction potential of reducing agent has to be matched with the dye for proper dyeing. Otherwise the problem of over reduction and under reduction may arise and leads to the change in shade. In conventional vat dyeing process, the vat dye is dissolved using hydrose, which is a powerful reducing agent followed by solubilizing with sodium hydroxide. This process creates very high pollution problem. In this study, an attempt has been made to replace hydrose by ferrous sulphate and hydrose combination as reducing agent on cotton fabric dyeing with vat dye and the results are compared with those of the treatment with conventional hydrose in terms of depth of shade, color fastness, color difference, tensile strength and effluent parameters. Among the ferrous sulphate + Hydrose combinations, 0.5g/L (10%) ferrous sulphate + 4.5g/L (90%) hydrose and 2g/L (40%) ferrous sulphate + 3g/L (60%) hydrose combinations as reducing agents give very good dyeing effect on the dyed cotton fabric with Bezathren Blue RS and Red LGG vat dyes respectively. These ferrous sulphate + hydrose combinations as reducing agents results higher color strength, lower BOD and COD values and higher fabric strength than hydrose. Therefore, hydrose can be replaced by ferrous sulphate + hydrose combinations depending on the reduction potential of a dye and by controlling the NaOH amount during dyeing. 2019-03-28T00:00:00Z