Acceleration of regeneration treatment for nanostructured bainitic steel welding by static recrystallisation

Abstract

In order to accelerate bainite transformation during regeneration treatment following nanostructured bainite steel welding, static recrystallisation mechanism is adopted to refine the coarse grain size during two-pass welding. Large mechanical deformation was introduced into the coarse grain zone of the first weld pass, where static recrystallisation would occur with thermal effect of the second weld pass. Static recrystallisation kinetics of nanostructure bainite was studied by two-pass hot deformation experiments. The explicit temperature function of two-pass welding was presented, and effect of welding parameters on static recrystallisation of the deformed coarse grain zone was analysed. Experimental results showed that grains in original coarse grain zone were greatly refined and that nanostructured bainite regeneration was remarkably accelerated.     

多重角色介入下重庆黄桷坪501仓库的更新

本文从政府、艺术工作者、企业三方关系的角度出发,对501仓库的更新模式进行了分析,并讨论了在重庆黄桷坪501仓库更新过程中不同角色的利益需求和角色作为,其中艺术工作者作为直接的获益者对物质空间的更新起了主导作用。本文主要从外部环境、建筑整体空间和室内空间三方面研究了501仓库的更新过程,分析了更新前后企业和艺术工作者的角色博弈和角色局限性。政府的介入匡正了角色关系,角色之间走向合作。501仓库更新过程中角色关系的变化表明,只有多重角色共同合作才能保证旧工业建筑的可持续更新。     

蜡油催化裂解工艺研究

以抚顺蜡油为原料,在FS-J1固定床反应器上利用自制的FL-J型蜡油催化裂解催化剂进行中试实验。在温度为340～380℃,空速为1～4h-1的不同工艺条件下,考察了催化剂的使用性能,以及产品分布和产品质量的影响。结果表明,此反应有较好的产品分布,产品性质理想。反应温度及空速对汽、柴油收率有显著影响。催化剂因积炭失活后,可通过器内烧焦再生使催化剂活性得到恢复,降低了生产成本。此工艺作为增产汽、柴油的手段有广阔的应用前景。     

Removal of Alkaline Catalysts from Polyols by Ion Exchange

Abstract

Resin regeneration is crucial in the feasibility of polyol purification by ion exchange. In order to get an economically viable commercial process, a new regeneration process, including initial and final methanol flushing steps and treating with a 4.5 M aqueous mineral acid solution, has been investigated. An important reduction in regeneration costs was reached by minimizing the amount of acid used and recycling one part of the regenerant solution to the process. The composition of regeneration effluents has been studied in order to recover their valuable components. This simple resin regeneration technique lends itself to a technically and economically viable commercial process for the treatment of polyol products.     

30万t／a芳烃抽提装置技术方案比选及优化

以充分利用中国工艺技术为原则,通过对几种芳烃抽提装王工艺技术的比较,中国石油吉林石化芳烃抽提装置采用国内研发的Sulfolane工艺(即环丁砜法)技术方案,对芳烃抽提装置进行优化和技术改进,采用新型爪式干式真空泵,使芳烃装置达到正常运行时无污水排放的目标.     

Formation of coke from propene over 5A adsorbents – influence of the binder on the coke composition, location and removal

Coke formation from propene was investigated at 623 K and P_propene=100 kPa on a pure 5A zeolite and an industrial adsorbent (5A zeolite 80 wt.%–binder 20 wt.%). The composition and location of coke molecules were determined as a function of time on stream. Coking on the pure zeolite was faster than on the industrial adsorbent. This result is mainly due to the trapping of coke precursors by the binder, and consequently a significant decrease in the amount of coke on the zeolite present in the adsorbent. While the coke deposited on the binder is very polyaromatic, the carbonaceous compounds formed on the zeolite and on the adsorbent are constituted at low coke content by mono-, bi-, tri- and tetra-alkyl aromatic components, and these compounds are sterically blocked in the -cages of the 5A zeolite. At high coke content, very heavy polyaromatic compounds appear and are certainly located on the external surface of the zeolite crystallites. Adsorption measurements of both samples show that coke is heterogeneously distributed in the zeolite pores. Whatever be the adsorbent, the partial oxidation of coke on highly coked samples caused an increase in the adsorption capacity. The first few steps of regeneration of coked samples remove the heavy polyaromatic molecules responsible for the pore blockage and thus liberate the pores which are not occupied by coke molecules.     

壁流式微粒过滤器电加热再生自动控制系统的研究

在前期对壁流式陶瓷微粒过滤器电加热分区再生方法进行完善的基础上,对自动控制系统进行了研究。介绍了再生方法、控制方案的选择、控制系统（数字ＣＭＯＳ电路）的设计原理等,并进行了分区、定时自动再生试验。试验表明,研制的再生自动控制系统设计合理、运行可靠。对于一些运行有规律的车辆（如城市公共汽车、码头、车站内用柴油机车辆、工程机械等）来说,只要能合理确定再生间隔,该再生系统具有一定的实用性。     

环己醇装置水合催化剂流失原因的分析

分析了环己烯水合催化剂流失的原因,结果表明：搅拌器转速、催化剂浓度、催化剂界面是影响催化剂流失的主要原因,催化剂的再生、劣化也是影响催化剂流失的原因;工艺优化条件：反应温度120℃,压力0．5MPa、搅拌器转速45r／min、催化剂质量分数20％、催化剂界面10％。工艺优化改进后效果显著。     

A regenerable Fe/AC desulfurizer for SO2 adsorption at low temperatures

A novel regenerable Fe/activated coke (AC) desulfurizer prepared by impregnation of Fe(NO₃)₃ on an activated coke was investigated. Experiment results showed that at 200 °C the SO₂ adsorption capacity of the Fe/AC was higher than that of AC or Fe₂O₃. Temperature-programmed desorption (TPD) revealed that H₂SO₄ and Fe₂(SO₄)₃ were generated on the desulfurizer upon adsorption of SO₂. Effect of desulfurization temperature was also investigated which revealed that with increasing temperature from 150 to 250 °C, the SO₂ removal ability gradually increases. The used Fe/AC can be regenerated by NH₃ at 350 °C to directly form solid ammonium-sulfate salts.     

Zirconium mesostructures immobilized in calcium alginate for phosphate removal

Eutrophication caused by the excessive supply of phosphate to water bodies has been considered as one of the most important environmental problems. In this study, the powder of zirconium mesostructure (ZM), which was prepared with the template of surfactant, was immobilized in calcium alginate for practical application and the resulting material was tested to evaluate the phosphate removal efficiency. Sorption isotherms and kinetic parameters were obtained by using the entrapped ZM beads with 30 to 60% of ZM. The maximum sorption capacity increased with the higher ZM content. Q _max in Langmuir isotherm was 51.74 mg/g for 60% of ZM with 7 mm of size. The smaller the particle size of the ZM beads, the faster the rate of phosphate removal, because the phosphate ions had less distance to reach the internal pores of the immobilized ZM beads. Chemical and electrochemical regeneration techniques were compared. Phosphates adsorbed on the ZM beads were effectively desorbed with NaCl, NaOH, and Na₂SO₄ solutions. An electrochemical regeneration system consisting of an anion exchange membrane between two platinum-coated titanium electrodes was successfully used to desorb and regenerate the phosphate-saturated ZM beads. Complete regeneration was reached under optimal experimental conditions. Chemical and electrochemical regeneration proved the reusability of the bead form of the entrapped ZM, and will enhance the economical performance of the phosphate treatment process.