用于PET薄膜回收的螺杆设计

根据PET薄膜的特点和高分子熔融态流动理论，分析了挤出回收用螺杆的各段结构，及螺杆参数选择，设计出大长径比、深槽、双排气、高效专用螺杆。     

宾馆酒店蒸汽冷凝水回收问题剖析

分析了宾馆酒店进行冷凝水回收所遇到的各种问题，提出了应对策略和解决方法，介绍了取得的应用效果。     

Pretreatment of Highly Polluted Pharmaceutical Waste Broth by Wet Air Oxidation

The preoxidation of a highly polluted waste pharmaceutical fermentation broth using wet air oxidation (WAO) has been studied as a possible method for the effective removal of organics. The applied (pre)treatment method should enhance the biotreatability of the pharmaceutical fermentation broth in terms of reduced initial toxicity and higher biodegradability. Preliminary experiments in the pilot biological treatment plant were successful only at low organic loads, whereas the system collapses at higher ones. The characterization of the fermentation broth was started by common physicochemical analysis, whereas several bioassays were used to determine its impact on biological treatment plants and the environment. Toxicity prior to and after WAO was determined using the acute Vibrio fischeri test, measurement of inhibition of O2 consumption, and the Daphnia magna acute test. Ready biodegradability of the treated and untreated broth has also been assessed. WAO experiments were accomplished in the 2?L batch reactor at different temperatures (240/280°C) and operating pressures. WAO experiments confirmed reduction of the toxicity toward microorganisms, whereas oxidized wastewater was more toxic to daphnids. Biodegradability of the oxidized broth has also been enhanced. Further work has been focused on designing appropriate combination of WAO and biological processes.     

Study of direct and indirect naphtha recycling to a resid FCC unit for maximum propylene production

To satisfy the increasing propylene demand, direct and indirect naphtha recycling schemes around an existing resid fluid catalytic cracking (FCC) unit were investigated. To this aim, light cracked naphtha (LCN), heavy cracked naphtha (HCN) and a PolyNaphtha (PN) oligomerisation product were cracked under a wide range of operating conditions over a commercial Y zeolite based equilibrium catalyst. Experimental data were acquired in three different units: a fixed bed bench scale unit, a fixed fluidised bed unit and an adiabatic circulating fluidised bed pilot plant. It was shown that FCC naphthas require high operating severities to crack, and that even then their conversion remains relatively moderate. Hence, direct recycling to the main riser does not seem a viable pathway to increase propylene product. Feeding FCC naphthas to a second reaction zone operating at high severity allows to increase the propylene yield in a significant manner. Increasing conversion, however, not only leads to higher LPG and propylene yields, but also results in very high dry gas yields. An alternative scheme was proposed, in which the olefinic C₄ and C₅ fractions are converted into a naphtha fraction through oligomerisation in a dedicated unit before being recracked in the secondary riser. As the highly olefinic oligomerised effluent mainly consist of dimerised and trimerised butenes and pentenes, this feed is more easily cracked and high conversions can be achieved. This indirect interconversion of butenes and pentenes into propylene therefore effectively allows to convert these butenes and pentenes into propylene, resulting in a significant increase in propylene yield. Each of the three main naphtha recycle options (directly to the main riser, directly to a secondary riser or indirectly via a light olefin oligomerisation unit) have been analysed and compared to a base case. In the evaluation of each of these schemes, all heat balance effects, both on the riser and the regenerator side, have been accounted for. The proposed process scheme with an indirect recycle via an oligomerisation unit enhances the already inherent flexibility of the FCC unit. The naphtha recycle can be turned on or off, the second reaction zone can be used to crack naphtha or to crack resid feed to maximise throughput, while the effluent of the oligomerisation unit can be recycled to the FCC unit for propylene production or hydrogenated and sent to gasoline and kerosene pool.     

变频调速技术在污水处理厂的应用

概述污水处理厂的一般工艺，简单介绍了风机、水泵等的节能特点，介绍了变频调速装置在污水处理厂各处理工段的应用。     

MITI projects on recycling

MITI has actively done R&D on industrial technology for waste and reclamation and so there are many research items from small scale to large scale. However, Ecofactory and researches on recycling of metallic materials are introduced here. Ecofactory was proposed by the Mechanical Engineering Laboratory and is now at the stage of the Leading Research, a new research scheme in AISt. Researches on recycling of metallic materials are being done with subsidy. Those researches should contribute to both the preservatin of the global environment and effective recycling of waste materials.Abbreviations AIST Agency of Industrial Science and Technology - MITI Ministry of International Trade and Industry - NEDO New Energy and Industrial Technology Development Organization     

Recovery of monomers and fillers from high-temperature-vulcanized silicone rubbers—combined effects of solvent, base and fillers

The depolymerization of high-temperature-vulcanized (HTV) silicone rubbers containing filler silica and alumina into cyclosiloxane monomers and spontaneous recovery of fillers were studied. First, HTV silicone rubber was treated with different types of solvents in the presence of KOH to find that a triad mixture of diethylamine, methanol and hexane was appropriate not only to dissolve the silicone rubber to a suspension but also to separate fillers completely by filtration. The filtrate was distilled to remove solvent first and then give pure cyclosiloxane monomers in 76–84% yields. Second, the rubbers were treated with other types of triad mixture of solvents and bases, e.g. tetramethylammonium hydroxide, hexane and diethylamine. After filtration, residue was again treated with the amine and hexane to recover clean fillers in 83–93% yields. Cyclosiloxane monomers were also obtained from the combined filtrates in 67–78% yields.     

Ecological aspects of the manufacture and application of highly pure liquid substances

The action mechanism for aggressive and highly pure media on fluoropolymer constructional elements is assumed to consist of two basic microeffects: destructive changes in the fluoropolymer and contamination of the environment. Our approach to a quantitative estimation of the physicochemical stability is based on logic similar to that of a thermodynamic model of a two‐component system. A fluoropolymer and changes in its microstructure are considered the first component of the system. The second component is composed of liquid media contaminated with fluoroorganic compounds extracted from the fluoropolymer. The proposed methods for delivering aggressive and highly pure fluids to consumers allow the exclusion of pollution from working areas with gaseous products through an exception to a number of intermediate stages of product transport. The discussed principles allow the creation of a modern, highly effective, and safe (with respect to the ecology and raw materials) production of aggressive liquid chemicals for consumers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 906–910, 2002     

Thermoplastic elastomeric composition based on maleic anhydride–grafted ground rubber tire

Ground rubber tire (GRT) powder was maleated in an internal mixer using maleic anhydride and dicumyl peroxide at 160°C. Maleated GRT was characterized by using X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, wettability, and differential scanning calorimetry. The physical properties of the dynamically vulcanized 60 : 40, rubber : plastic composition based on acrylated high‐density polyethylene as the plastic phase and ethylene propylene diene rubber containing maleated GRT as the rubber phase were found to be greater than the corresponding composition containing nonmaleated GRT. The blend was found to be reprocessable, like themoplastic elastomers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 370–378, 2002; DOI 10.1002/app.10348     

Water‐soluble/dispersible cationic pressure‐sensitive adhesives. I. Adhesives from solution polymerization

Pressure‐sensitive adhesives (PSAs) have long been a problem as sticky contaminants for paper recycling mills. The main problem associated with such stickies is that the PSAs in the waste papers deposit on the felts, press rolls, and drying cylinders of paper machines, and this creates problems with paper formation, reducing the paper quality and paper machine runnability. The annual cost of stickies to the U.S. paper industry is estimated to be about $600,000,000–650,000,000. To solve this problem, a series of cationic water‐soluble/dispersible PSAs have been synthesized by the free‐radical solution polymerization of butyl acrylate and [3‐(methacryloylamino)propyl]trimethylammonium chloride in ethanol. The PSA end‐use properties, repulpability in paper recycling, and the effects on the properties of recycled paper products have been studied. The cationic PSAs can be dissolved or dispersed in water if the cationic charge density in the PSA backbone is controlled, and so they do not deposit as stickies during recycling and papermaking processes. Because the PSAs are cationically charged, they can easily be removed from the papermaking system by adsorption onto the negatively charged fibers and fine surfaces. Furthermore, the adsorbed colloidal or dissolved PSAs have little effect on the final paper properties. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1624–1630, 2003