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901.
通过对循环水全有机碱性水质稳定剂实际应用情况的研究,结合饱和指数(Is)、稳定指数(RIS)、结垢指数(PSI)等指数的计算,在保证循环水水质稳定的前提下,通过适度加酸改变原设计的自然pH值运行方式,将循环水浓缩倍数由3倍提升至5倍运行,达到降低循环水药剂消耗和补水耗量的同时减少排污水量,实现节能减排的目的。 相似文献
902.
针对尿素装置氨水槽氨水浓度高,造成水解一解吸系统超压以及中压、常压系统尾气放空氨含量增多等问题,进行原因分析,制定相应的处理措施,以达到降低氨耗的目的. 相似文献
903.
904.
905.
针对湿式喷射混凝土工艺在冀中股份章村矿的应用情况,阐述了湿喷工艺的流程、技术参数以及作业人员配备情况。从湿式喷射混凝土的回弹率、粉尘浓度、混凝土强度、喷浆工效、综合成本比较等方面详细介绍了湿式喷浆工艺的经济性、先进性、优越性。 相似文献
906.
结合实际生产情况,介绍硝酸镁法生产浓硝酸的主要控制指标(系统负压、温度、硝酸镁浓度、物料配比等)及调节手段,从而达到优质高产低耗的目的。 相似文献
907.
Sourav Mondal Raka Mukherjee Somak Chatterjee Sirshendu De 《American Institute of Chemical Engineers》2014,60(6):2354-2364
Adsorption has been found to be significant in ultrafiltration by mixed matrix membrane. Removal of very low molecular weight solutes compared to the molecular weight cut off of the membrane is facilitated by adsorption. The modeling of the adsorption coupled with concentration polarization is presented based on the mathematical approach developed by Gekas et al. (Gekas et al. Chem Eng Sci. 1993;48:2753–2765), from the first principles. However, extensive modifications were included in theoretical development including those suggested by Ruiz‐Bevia et al. (Ruiz‐Bevia et al. Chem Eng Sci. 1997;52:2343–2352). The developed model captured the rejection dynamics with the help of retention factor. The model equations were solved under the framework of boundary layer analysis, using the integral approach. Effects of the adsorption isotherm and the different parameters affecting the system performance were also investigated. Further, experimental validation of the model results with two different mixed matrix ultrafiltration studies was also elucidated. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2354–2364, 2014 相似文献
908.
Ketinun Kittipongpittaya Atikorn Panya Leqi Cui David Julian McClements Eric Andrew Decker 《Journal of the American Oil Chemists' Society》2014,91(11):1955-1965
Association colloids formed by surface active minor components play an important role in the oxidative stability of bulk oils. To imitate the formation of nanostructures in refined oils, multiple surface active minor components including phospholipids, free fatty acids, diacylglycerols and sterols were added to stripped corn oil. The critical micelle concentration (CMC) of the mixed components was determined. The impact of mixed minor components at below and above their CMC on oxidative stability of bulk oil and on antioxidant activity of α-tocopherol and Trolox was investigated. The CMC of the mixed surface active components in bulk oil was 20 µmol/kg oil in the presence of 383 ± 2 ppm of water. 1,2-Dioleoyl-sn-glycero-3-phosphocholine (DOPC) played an important role on the formation of association colloids since it was the most important component in forming the association colloids as confirmed by CMC and fluorescence probe studies. The association colloids formed by the mixed components showed prooxidative activity in bulk oil as determined by monitoring the formation of lipid hydroperoxide and hexanal. The activity of α-tocopherol or Trolox was not changed by mixed components association colloids. These results suggest that association colloids both physically and chemically impacted the oxidative stability and activity of antioxidants in bulk oil. 相似文献
909.
Leqi Cui Ketinun Kittipongpittaya D. Julian McClements Eric A. Decker 《Journal of the American Oil Chemists' Society》2014,91(11):1931-1937
Phospholipids are important minor components in edible oil that play a role in lipid oxidation. Surface active phospholipids have an intermediate hydrophilic–lipophilic balance value, which allows them to form association colloids such as reverse micelles in bulk oil. These association colloids can influence lipid oxidation since they create lipid–water interfaces where prooxidants and antioxidants can interact with triacylglycerols. In this study, we examined the formation of reverse micelles in a stripped oil system by dioleoyl phosphoethanolamine (DOPE) and the effect of these physical structures on lipid oxidation kinetics. The critical micelle concentration (CMC) of DOPE was approximately 200 µmol/kg oil at 45 °C. Oxidation kinetics studies showed that DOPE was prooxidative when it was above its CMC (400 and 1,000 µM), reducing the lag phase from 14 days (control) to 8 days. The addition of combinations of DOPE and dioleoyl phosphocholine (DOPC) resulted in formation of mixed micelles with a CMC of 80 µmol/kg oil at 45 °C. These mixed micelles were also prooxidative when concentrations (100 and 500 µM) were above the CMC, decreasing the lag phase from 14 to 8 days. These findings provide a better understanding of the role of phospholipids in lipid oxidation of edible oil and could contribute to better antioxidant solutions. 相似文献
910.
Research was conducted, which aim was to evaluate quantitative and qualitative PCB changes in sewage sludge during mesophilic digestion, and the influence of those compound concentration above acceptable level (1.9 mg kg−1 of sludge dry matter), also nickel and cadmium ions, on mesophilic digestion process. Before and after the digestion, concentration of seven PCB congeners, Ni and Cd in particular chemical fractions of the sludge was analyzed. 相似文献