The Effect of Reduction Parameters on Iron Nugget Production From Composite Pellets

Composite pellets which contain a reducing agent and are produced only by cold bonding process are improved instead of traditionally hardened pellets by sintering. The new ironmaking technologies that are able to utilize these pellets have been developed from pilot plant to commercial scale. Iron nuggets which have a similar composition to pig iron can be produced by using composite pellets at high temperatures (1350–1400°C) and in a short reduction time (15–20 min) by smelting reduction process. In this study, the effect of reduction parameters and basicity of composite pellets on the reduction properties and product quality are investigated. Composite pellets containing magnetite concentrate with a reducing agent (coke) and a flux are processed at different temperature and at times by smelting reduction process. The increasing temperature and time has a positive effect on reduction and melting of the pellets. Excessive carbon prevents the metal droplets from coalescing. The iron nugget that is produced from the sample with the basicity (CaO/SiO₂) of 0.68 has the optimal physical and chemical properties. It is also determined that a decrease or increase of basicity has a negative effect on the properties of the iron nuggets.     

Use of ionic liquid in leaching process of brass wastes for copper and zinc recovery

Brass ash from the industrial brass manufacturer in Turkey was leached using the solutions of ionic liquid （IL） 1-butyl-3-methyl-imi-dazolium hydrogen sulfate （[bmim]HSO4） at ambient pressure in the presence of hydrogen peroxide （H2O2） and potassium peroxymonosulfate （oxone） as the oxidants. Parameters affecting leaching efficiency, such as dissolution time, IL concentration, and oxidizing agent addition, were investigated. The results show that [bmim]HSO4 is an efficient IL for the brass ash leaching, providing the dissolution efficiencies of 99%for Zn and 24.82%for Cu at a concentration of 50vol%[bmim]HSO4 in the aqueous solution without any oxidant. However, more than 99%of zinc and 82%of copper are leached by the addition of 50vol%H2O2 to the [bmim]HSO4 solution. Nevertheless, the oxone does not show the promising oxidant behavior in leaching using [bmim]HSO4.     

Utilization of waste polyethylene terephthalate as a reducing agent in the reduction of iron ore composite pellets

The increasing consumption of plastics inevitably results in increasing amounts of waste plastics. Because of their long degradation periods, these wastes negatively affect the natural environment. Numerous studies have been conducted to recycle and eliminate waste plastics. The potential for recycling waste plastics in the iron and steel industry has been underestimated; the high C and H contents of plastics may make them suitable as alternative reductants in the reduction process of iron ore. This study aims to substitute plastic wastes for coal in reduction melting process and to investigate their performance during reduction at high temperature. We used a common type of waste plastic, polyethylene terephthalate （PET）, because of its high carbon and hydrogen contents. Composite pellets containing PET wastes, coke, and magnetite iron ore were reduced at selected temperatures of 1400 and 1450℃ for reduction time from 2 to 10 min to investigate the reduction melting behavior of these pellets. The results showed that an increased temperature and reduction time increased the reduction ratio of the pellets. The optimum experimental conditions for obtaining metallic iron （iron nuggets） were reduction at 1450℃ for 10 min using composite pellets containing 60% PET and 40% coke.     

Effects of vitamin E supplementation on fattening performance, non-carcass components and retail cut percentages, and meat quality traits of Awassi lambs

This experiment was carried out to evaluate the effects of vitamin E supplementation on growth, non-carcass components and retail cut percentages, and meat quality traits of Awassi male lambs at approximately 8 months of age. The lambs were divided into two groups as control (CG, n=12) and experimental (VG, n=12) at the beginning of the fattening period. The CG and VG lambs were fed with a concentrate and grass hay close to ad-libitum by biweekly adjustment of the amount offered. In addition, the VG received a supplement of 45 mg vitamin E per lamb per day during a 75-day fattening period. Inital weight, final weight, daily weight gain and feed conversion efficiency were 31.8±1.40 kg, 45.5±1.37 kg, 183±13 g and 7.6 for CG, 32.5±1.45 kg, 46.7±1.42 kg, 189±15 g and 7.0 for VG, respectively. Vitamin E supplementation did not have a statistically significant effect on animal performance traits, non-carcass components and retail cut percentages, but produced an 8.1% improvement in feed conversion efficiency. After slaughter, carcasses were chilled at 4?°C for 24 h. Then, the carcasses were dissected into wholesale cuts, and m. longissimus dorsi (LD) muscles excised. The samples of muscle were subjected to moisture, protein, ether extract and ash analyses. Samples were cooked for shear test and cooking yield measurements. There were no significant differences between CG and VG lamb groups in chemical composition of meat samples from the LD muscles. Though the influence of vitamin E supplementation on color parameters (L*, a*, b*) was not statistically significant, the mean a* (redness) values decreased on days 2 and 4 and increased on days 7 and 12 of the storage period. However, the a* values of muscles from the VG were higher than those grouping CG. L* and a* values in LD muscle from vitamin E-treated lamb groups were also preserved for a period of 12 days of maturation. In this study, drip loss was relatively preserved by vitamin E supplementation to the diet of animals. The results showed that vitamin E supplementation to the diet of Awassi male lambs at an inclusion rate over the amount of nutritional recommendations relatively reduced lipid oxidation, drip loss and tended to maintain meat redness.     

Effects of vitamin E supplementation on performance and meat quality traits of Morkaraman male lambs

This research was carried out to determine the effects of vitamin E supplementation on meat quality traits of approximate 8 months of age Morkaraman male lambs. The lambs were divided into two groups-control (CG, n=7) and experimental (VG, n=6)-at the beginning of fattening period. The diet given to the CG and VG consisted of concentrate and grass hay. In addition, the VG received a supplement of 45 mg vitamin E per lamb in a day during a 75-day fattening period. At the end of the study, average daily weight gain and feed conversion efficiency values as to feed basis were found to be 208 g and 6.3 for CG and 223 g and 6.0 for VG groups, respectively. Vitamin E supplementation resulted in 8.8% improvement in feed conversion efficiency. In the same way, vitamin E supplementation resulted in 6.7% increase in daily weight gain. Slaughter and carcass characteristics of lambs were also determined, but fattening performance, slaughter and carcass characteristics were not significantly different between groups. The effects of vitamin E on meat characteristics, meat colour (L*, a* and b*), thiobarbituric acid reactive substances content (TBARS), drip loss and pH were determined using m. longissimus dorsi (LD) muscles obtained from CG and VG. Though the effect of vitamin E supplementation on most of the meat quality traits was not statistically significant (P>0.05), L* and a* values in LD muscle from VG were preserved for a period of 12 days of maturation. In addition, a* (redness) tended to increase slightly. TBARS values in samples from CG were found to be higher than those of vitamin E treatment group. In this study, it was also concluded that drip loss was relatively preserved by vitamin E supplementation. In conclusion, vitamin E supplementation of Morkaraman male lambs at an inclusion rate over the amount of nutritional recommendations, significantly reduced lipid oxidation, drip loss and tended to maintain meat redness.     

Effects of dietary humate supplementation to broilers on performance,slaughter, carcass and meat colour

BACKGROUND: This experiment was designed to examine the effect of dietary humate supplementation primarily on pH and colour parameters of carcasses, breast fillets and drumsticks and, secondarily on performance and carcass characteristics in broilers. RESULTS: A total of 240 male broiler chicks (Ross‐308) were randomly allocated to four dietary treatments varying in supplemental humate level (0, 0.1, 0.2 and 0.3% for H₀, H₁, H₂ and H₃). Dietary humate supplementation did not affect performance traits and slaughter, hot carcass weights and yields. Carcass‐related variables (pH, L*, a*, b*, H* and C*) were responsive to the dietary treatments. The L*, a*, b*, and C* values for drumstick muscles were higher than those for breast muscles. Except for the L* value, meat colour parameters changed due to packaging. The a* value was higher and b* value was lower for vacuum packaged breast and drumsticks than for those aerobic packaged. Storage period affected colour parameters; while L*, b*, H* and C* values were higher for drumstick skin than for drumstick meat; the a* value was greater in drumstick meat than in skin. CONCLUSION: pH and colour parameters of carcasses, breast fillets and drumsticks of broilers were improved by dietary humate supplementation. However, responses of broiler performance and slaughter and carcass characteristics were minimal. Copyright © 2008 Society of Chemical Industry     

Effect of Dietary Ram Horn Hydrolysate (RHH) on the pH and Color Characteristics of Carcasses,Breast Fillets and Drumsticks of Broilers

This study was conducted to define the effects of ram horn hydrolysate (RHH) on the pH and color properties of carcasses and dissected products in broilers. Two-hundred and forty male broiler chicks (Ross-308) were fed with basal diets supplied with RHH for 4 wks. Chicks were allocated to four dietary treatments (H₀, H₁, H₂ and H₃ groups) in a completely randomized experimental design. Feed and water were offered ad libitum consumption and lightening was continuous throughout the experimental period. H₀ group was fed only the basal diet and given normal drinking water. Treatment groups were fed with basal diet plus a 1% (H₁), 2% (H₂), and 3% (H₃)-RHH-added water in place of normal drinking water to meet the daily water requirements of chickens from 1 to 28 days of ages. At the end of the trial all birds were slaughtered, then the ranges of pH and skin color of carcasses were determined at various times during the first 24 hour (1, 3, 7, 12, 17, and 24). After standard dissection of carcasses, breasts and drumsticks were divided into two groups for vacuum and aerobic packaging. Packed breasts and drumsticks were stored at 3 60.58 C, for 12 days, and the color values were determined. The pH values of H₃ group were lower than those of H₀, H₁ and H₂ groups (p < 0.05). The lightness (L*), redness (a*) and yellowness (b*) values increased during the 24-h period. The H₀ group had the higher b* values than those of RHH-added groups (p < 0.05). The L*, a* and b* values of drumstick meats were higher than those of the breast meats (p < 0.05). The values of b* in aerobic packaged breasts and drumsticks were higher than the vacuum packaged (p < 0.05) treatments. The b* values increased with storage. The a* values of RHH-supplied groups were higher than that of the control (p < 0.05), while b* value of control was higher than those of the RHH-supplemented groups (p < 0.05). While the L* and b* values of drumstick skin were higher than that of drumstick meat, a* values in drumstick meats were higher (p < 0.05). The vacuum packaging increased the a* value during storage. As a result, the use of RHH in broiler diets had a significant effect on the L*, a*, and b* values of carcasses and dissected tissue (p < 0.01).     

Effects of dietary humate supplementation on performance,egg quality and egg yolk fatty acid composition in layers

BACKGROUND: The objective of this study was to determine the effects of humate on performance, egg quality and egg yolk fatty acid (FA) composition in laying hens. RESULTS: Six hundred and thirty White Lohmann layers at 46 weeks of age were assigned randomly to seven groups, each with 18 replicate cages of five hens. Control diet (C) and C supplemented with 0.10 (H1), 0.15 (H2), 0.20 (H3), 0.25 (H4), 0.30 (H5) and 0.35 (H6) wt% humate were offered for 25 weeks. Humate supplementation improved performance variables and egg quality indices including shape index, yolk colour, albumen index, yolk index and Haugh unit, but not specific gravity, shell strength and shell thickness. Average feed intake (g), egg production (%), egg weight (g) and feed efficiency for the groups were 118.9, 87.2, 68.1 and 2.07 (C), 118.8, 87.7, 66.3 and 2.08 (H1), 119.3, 89.8, 66.6 and 2.03 (H2), 119.5, 88.9, 66.9 and 2.05 (H3), 118.3, 86.5, 66.9 and 2.11 (H4), 119.3, 90.6, 66.9 and 2.02 (H5) and 123.6, 88.5, 66.1 and 2.16 (H6) respectively. Palmitoleic acid concentration increased from 4.34% (C) to 7.65% (H5) and stearic acid concentration decreased from 7.39% (C) to 5.39% (H6) of total FA. CONCLUSION: Dietary humate supplementation improved performance, inner egg quality parameters and egg yolk fatty acid composition. Copyright © 2008 Society of Chemical Industry