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Ho-Cheol Kang 《Polycyclic Aromatic Compounds》2016,36(5):745-757
The separation of nitrogen heterocyclic compounds (NHC) contained in a model coal tar fraction comprising four kinds of NHC [indole (In), quinoline (Q), iso-quinoline (iQ), quinaldine (Qu)], three kinds of bicyclic aromatic compound (BAC) [1-methylnaphthalene (1MN), 2-methylnaphthalene (2MN), dimethylnaphthalene (DMN) mixture with ten structural isomers (DMNs; regarded as one component)], biphenyl (Bp), and phenyl ether (Pe) was examined by batch cocurrent three stages equilibrium extraction. The model coal tar fraction used as a raw material in this work was prepared according to the components and compositions contained in coal tar fraction (distilled temperature ranges: 240–265°C). An aqueous solution of formamide and that of methanol were used as solvent, respectively. The distribution coefficient of the entire NHC (NHCs) summed four kinds of NHC was much larger than that of the entire BAC (BACs) summed three kinds of BAC, Bp, and Pe. Irrespective of solvent used in this work, the NHCs was recovered more than 90% through three stages of the equilibrium extraction. The selectivity of NHCs based on BACs obtained through the 3 stages equilibrium extraction using an aqueous solution of formamide was higher 3.6–8 times than that using an aqueous solution of methanol. Furthermore, we investigated the recovery process of NHCs contained in coal tar fraction using the formamide experimental results obtained from this work. 相似文献
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介绍气压连续过滤机的结构、过滤性能和技术经济指标。气压连续过滤机扬弃真空过滤机和板框或厢式压滤机优缺点 ,具有较大的生产能力并可连续作业。GYL 3气压连续过滤机与GN 8内滤式真空过滤机相比 ,过滤面积小 5m2 ,而产能增加10 % ,装机功率却减少 44 % ,节电 4 73万kW·h/a ,设备费用减少一半 ,在过滤浮选精煤时 ,滤饼水分将降低 8%~ 12 %。 相似文献
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针对钢铁企业的热轧批量计划编制问题,考虑了热轧生产工艺规程、同宽板坯连轧长度限制等约束,建立基于不确定旅行商数的多旅行商问题(MTSP)的热轧批量计划数学模型,把轧制单元计划数最小化和紧邻轧制板坯间轧制宽度、厚度、硬度差异而造成的总惩罚值最小化作为优化目标。结合模型的实际情况,采用基于两交换启发式的改进遗传算法对问题进行求解。最后,利用某钢厂的实际生产数据进行计算试验,同时对结合传统遗传算法和改进遗传算法的优化情况进行对比和结果分析,模型的正确性和算法的有效性得到了验证。 相似文献
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Quality‐relevant fault diagnosis with concurrent phase partition and analysis of relative changes for multiphase batch processes 下载免费PDF全文
Chunhui Zhao 《American Institute of Chemical Engineers》2014,60(6):2048-2062
Multiplicity of phases as indicated by changes of process characteristics is an inherent nature of many batch processes for both normal and fault cases. To more efficiently perform online fault diagnosis via reconstruction for multiphase batch processes, the phase nature and the relationship between normal and fault cases within each phase should be deeply addressed. This article proposes a quality‐relevant fault diagnosis strategy with concurrent phase partition and analysis of relative changes for multiphase batch processes. First, a concurrent phase partition algorithm is developed. The basic idea is to track the changes of process characteristics at normal and fault statuses jointly so that multiple sequential modeling phases are identified simultaneously for both normal and fault cases. Then, the relative changes from the normal status to each fault case are analyzed in each phase to reveal the specific fault effects more efficiently. The fault effects are decomposed in two different monitoring subspaces, principal subspace, and residual subspace, by capturing their different roles in removing out‐of‐control signals. The significant increases relative to the normal case are judged to be responsible for the concerned alarm monitoring statistics in each phase. The others are composed of general variations that are deemed to still follow normal rules and thus insignificant to remove alarm monitoring statistics. Those alarm‐responsible fault deviations are then used to develop reconstruction models which can more efficiently recover the fault‐free part for online fault diagnosis. The proposed algorithm is illustrated with a typical multiphase batch process with one normal case and three fault cases. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2048–2062, 2014 相似文献