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31.
从烧结矿冷却并回收其余热的角度出发,介绍了利用烧结机尾落矿空间,采用喷吹空气装置对烧结矿进行冷却的小型模拟试验,从测出的结果来看,有可能成为一种新的烧结矿冷却方式。 相似文献
32.
从废旧锌锰电池中回收锌和锰的工艺研究 总被引:1,自引:0,他引:1
高玉华 《有色金属再生与利用》2006,(7):19-20
废旧锌锰干电池经过剖开、焙烧处理,去除汞和碳粉,再用硫酸浸取,滤液采用沉淀法分离锌和锰。锌和锰的回收率分别为94.5%和93.6%。 相似文献
33.
介绍235/75R15 FRD78非对称花纹雪地轮胎的设计。结构设计:外直径722 mm,断面宽241 mm,行驶面宽度179 mm,行驶面弧度高7.5 mm,胎圈着合直径375 mm,胎圈着合宽度197.8 mm,断面水平轴位置(H1/H2)0.97729,胎面采用4条纵向花纹沟槽设计,花纹深度9 mm,花纹饱和度69.18%,花纹周节数36。施工设计:胎面采用分层挤出,胎侧采用双复合设计,冠带层采用锦纶66帘线,1#和2#带束层使用3×0.30HT钢丝帘线,胎体采用高模量低收缩聚酯帘线,采用一次法成型机成型、液压硫化机和氮气硫化工艺硫化。成品性能试验结果表明,轮胎的充气外缘尺寸、强度性能、耐久性能和高速性能均达到相应设计和企业标准要求。 相似文献
34.
35.
IATF 16949:2016质量管理体系是为汽车相关产品的设计、开发、生产及相关装配和安装服务的。介绍IATF 16949:2016质量管理体系的核心原则和质量管理过程中的五大重要工具。该体系结合策划、实施、检查、处置(PDCA)循环与基于风险预防的思维,能够帮助轮胎企业提高整体绩效,满足配套主机厂的质量管理要求,提升企业核心竞争力,为推动企业可持续发展奠定良好基础。 相似文献
36.
研究2+2×0.32ST钢丝帘线替代2+2×0.35HT钢丝帘线在半钢子午线轮胎带束层中的应用。结果表明:与2+2×0.35HT钢丝帘线相比,2+2×0.32ST钢丝帘线的强度更高、直径更小、耐疲劳性能更好;在轮胎带束层中用2+2×0.32ST钢丝帘线替代2+2×0.35HT钢丝帘线后,工艺性能良好,成品轮胎的充气外缘尺寸变化不大,强度性能、高速性能、耐久性能和耐水压性能均能满足设计和国家标准要求,滚动阻力降低,同时有效减小了轮胎中的钢丝帘线和胶料用量,降低了生产成本。 相似文献
37.
Surface functionalization of blast furnace slag with sulfamic acid(a zwitterion) was performed for the removal of Cr~(3+) and methylene blue dye(MB) from water samples. The slag functionalization process was optimized using Response Surface Methodology Design. Statistical analysis of the parameters that include the sulfamic acid amount(A), reaction time(B), and temperature(C) revealed that(A) increase had a negative effect on the adsorption of both pollutants by the zwitterion slag, whereas(B) and(C)increase presented a positive impact. At the optimum condition of 2 g sulfamic acid amount, 50 min reaction time and 37 °C temperature, the prepared slag showed a removal efficiency of more than 90% for both Cr~(3+) and MB. Surface characterization by SEM/EDS, FTIR, XPS and surface area analyser, showed an improvement in surface properties and the incorporation of zwitterionic NH_2~+ and S@O groups of sulfamic acid. Adsorption isotherm and kinetic studies conducted with the zwitterion slag showed the adsorption process was suited to Freundlich isotherm model and pseudo-second-order kinetic model.The thermodynamic study conducted revealed the spontaneity of the process based on the calculated negative DG(Gibb's free energy) values. The prepared zwitterion slag offered easy regeneration with dilute HCl solution and showed a considerable removal(Cr3+: 65% and MB: 80%) for both pollutants even after 3 cycles of usage. 相似文献
38.
Kin Kit Fong Inn Shi Tan Henry Chee Yew Foo Man Kee Lam Adrian Chiong Yuh Tiong Steven Lim 《中国化学工程学报》2021,33(5):297-305
The rising production of produced water from oilfields had been proven to bring detrimental environmental effects. In this study, an efficient, recyclable, and environmental-friendly reduced graphene oxide immobilized κ-Carrageenan hydrogel composite(κCa GO) was fabricated as an alternative sorbent for crude oil-in-water demulsification. Polyethyleneimine(PEI) was employed to form a stable hydrogel composite. The conditions for the immobilization of graphene oxide(GO) on PEI-modified κ-Carrageenan(κC) beads were optimized appropriately. An immobilization yield of 77% was attained at 2% PEI, 2 h immobilization activation time, and p H6.5. Moreover, the synthesized κCa GO is capable of demulsification with an average demulsification efficiency of 70%. It was found that the demulsification efficiency increases with salinity and κCa GO dosage, and it deteriorates under alkaline condition. These phenomena can be attributed to the interfacial interactions between κCa GO and the emulsion. Furthermore, the κCa GO can be recycled to use for up to six cycles without significant leaching and degradation. As such, the synthesized κCa GO could be further developed as a potential sorbent substitute for the separation of crude oil from produced water. 相似文献
39.
Lei Ma Hongxia Lv Haonan Yu Lingtong Kong Rongyue Zhang Xiaoyan Guo Haibo Jin Guangxiang He Xiaoyan Liu 《中国化学工程学报》2021,33(5):286-296
A series of high oil-absorption resins with low cross-linking degree were synthesized by suspension polymerization using stearyl methacrylate(SMA), 2-Ethylhexyl methacrylate(EHMA), and styrene(St) as monomers.Response surface methodology(RSM) with central composite design(CCD) was also applied to determine the optimal parameters that are mainly known to affect their synthesis. Thus, the effects of the monomer mass ratio(EHMA:SMA), the rigid monomer(St) dosage, the porous agent(acetone) dosage, and their pairwise interaction on the resin's oil-absorption capacity were analyzed, highlighting PSES-R_2 as the resin with the optimum performance. The pure oil-absorption rates of PSES-R2 for gasoline, diesel, and kerosene were 11.19 g·g~(-1),16.25 g·g~(-1), and 14.84 g·g~(-1), respectively, while the oil removal rates from oily wastewater were 98.82%,65.11%, and 99.63%, respectively. 相似文献
40.
Due to the high salt content of coal chemical wastewater, pipeline fouling often occurs during wastewater treatment. Fouling will cause the diameter of the pipe to shrink or even block, which is not conducive to the safe and stable operation of the wastewater treatment process. In this paper, the experimental device was designed by using FLUENT software and the fouling deposition mechanisms at different flow velocities and different positions in a 90 deg bend were studied. The experimental results show that when the flow velocity is between 0.2 m·s~(-1) and 0.3 m·s~(-1), the thickness of fouling layer was positively correlated with the flow velocity; when the flow velocity is equal to 0.4 m·s~(-1), the formation of fouling is the most serious; when the flow velocity is between 0.4 m·s~(-1) and 0.7 m·s~(-1), the thickness of fouling layer was negative correlation with the flow velocity; with the increase of inlet velocity, the time for sediment point to develop into sediment surface is shortened. The fouling layer is easy to fall off because of the large shear force on the wall surface of the inner bend of the 90° elbow, so the density of sediment at this position is high. 相似文献