黄土与砂土液化特性的对比──土液化与减灾防灾

基于系统的试验 ,总结已有成果 ,研究了饱和黄土和砂土液化在液化机理、液化判别标准、影响液化的因素、孔压和应变的发展等方面的异同之处。研究表明 ,由于在液化机理上存在差异 ,导致二者动荷载下的孔压和应变发展特点有显著差别 ;同一因素对二者液化性状的影响可能相似 ,也可能不同 ;在动三轴液化试验中 ,黄土和砂土均可采用初始液化作为液化的判别标准。     

Liquefaction process for a hydrothermally treated waste mixture containing plastics

Most landfilled plastic waste is a mixture or is in the form of composites with incombustible wastes such as glass, metals, and ceramics. After hydrothermal treatment, including a steam-explosion process, the separation of mixed waste (MW) into organic and inorganic substances becomes easy. However, the effect of hydrothermal pretreatment on the subsequent liquefaction of organic substances from MW is not obvious. In this study, the effects on the liquefaction of polystyrene and high-density polyethylene are discussed. Moreover, optimum conditions for the liquefaction of organic substances from hydrothermally treated MW are identified. By means of this hydrothermal pretreatment, including the steam-explosion process, polystyrene and high-density polyethylene can be significantly converted to oil by liquefaction at 300°–400°C. In comparison with liquefaction of hydrothermally pretreated mixed waste (HMW) at 300°–400°C with a batch type reactor, the yield of oil increases significantly on liquefaction using a semi-batch type reactor. It is considered that the radical chain and termination reactions among the radicals from HMW were inhibited in the semi-batch type reactor. On liquefaction of HMW in a semi-batch reactor, the conversion of HMW to oil was enhanced on increasing the liquefaction temperature to 350°C and the holding time to 60 min. Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6     

高压喷射技术加固地基的工程实践

概述了在辽宁大洼县田庄台抽水站地基处理工程中采用高压喷射注浆技术的实践经验，并介绍了从工程勘察、方案选择、设计、施工和检测的全过程。此项技术，经过长期沉降观测取得了良好的加固成果。     

Life-cycle assessment of a waste refinery process for enzymatic treatment of municipal solid waste

Decrease of fossil fuel dependence and resource saving has become increasingly important in recent years. From this perspective, higher recycling rates for valuable materials (e.g. metals) as well as energy recovery from waste streams could play a significant role substituting for virgin material production and saving fossil resources. This is especially important with respect to residual waste (i.e. the remains after source-separation and separate collection) which in Denmark is typically incinerated. In this paper, a life-cycle assessment and energy balance of a pilot-scale waste refinery for the enzymatic treatment of municipal solid waste (MSW) is presented. The refinery produced a liquid (liquefied organic materials and paper) and a solid fraction (non-degradable materials) from the initial waste. A number of scenarios for the energy utilization of the two outputs were assessed. Co-combustion in existing power plants and utilization of the liquid fraction for biogas production were concluded to be the most favourable options with respect to their environmental impacts (particularly global warming) and energy performance. The optimization of the energy and environmental performance of the waste refinery was mainly associated with the opportunity to decrease energy and enzyme consumption.     

碱性催化剂对农业废物液化产生生物油和气体的影响

采用热化学处理法对农业废物玉米秸秆和苹果渣进行处理,3种碱性物质Na2CO3、K2CO3和KOH作为催化剂,都能不同程度提高液化生物油收率、减少固体残渣收率.但碱性催化剂会降低气体收率,因而不适合作为以获得气体产物为目的的生物质气化试验的催化剂.就增加液化生物油收率方面而言,Na2CO3的催化效果最好,KOH催化效果次之,K2CO3的催化效果最差.     

Evaluation of Eremurus spectabilis for production of bio-oils with supercritical solvents

Eremurus spectabilis samples were liquefied in organic solvents (methanol, ethanol and acetone) with (sodium hydroxide and ferric chloride) and without catalyst in a cylindrical reactor at temperatures of 270, 290 and 310 °C under supercritical conditions. The effects of liquefaction parameters such as temperature, catalyst and solvent on product yields were investigated. The liquid products were extracted with diethyl ether and benzene using an extraction procedure. The product yields in supercritical methanol, ethanol and acetone were found to as 41.6%, 53.8% and 64.3% in the non-catalytic runs at 310 °C, respectively. The highest conversion was obtained in supercritical acetone in the presence of ferric chloride (10%) at same temperature in the catalytic runs. The produced liquids in acetone were analyzed and characterized by elemental, Fourier transform infrared spectroscopy (FT-IR), gas chromatography–mass spectrometry (GC–MS). The liquid products (bio-oils) obtained with acetone contained various types of components including aromatics, nitrogenated and oxygenated compounds. As the bio-oils obtained exhibit high heat values, E. spectabilis is presented as a potential feedstock candidate for production of bio-fuels or valuable chemicals.     

液化地区房屋震害预测

本文研究与液化区房屋震害预测有关的四个问题.对液化区房屋震害资料和经验进行了分析.给出了测定土壤震陷特性的标准试验方法,获得了各种土壤的震陷参数.提出了估计房屋震陷的简化分析方法.在这些工作的基础上,建立了一个预测液化区房屋震害的方法.     

Damage to structures due to liquefaction in the Japan Sea earthquake of 1983

A strong earthquake of magnitude of 7.7 hit the northeast part of Japan on 26th May 1983. Because 100 persons were killed by tsunami, the disaster created a sensation throughout Japan, but there was also a large amount of damage to structures due to the earthquake. Highways, railways, bridges, harbours, levees and private houses were damaged severely in Aomori and Akita prefectures. A great portion of the damage was caused by liquefaction of sand.
This is a prompt report of earthquake damage to structures due to liquefaction. The paper describes general aspects of the damage to structures, with some typical examples are mentioned in more detail. Preliminary results of investigation after the earthquake are also presented to describe the liquefaction phenomena in the earthquake.     

Study on static and dynamic strength characteristics of tailings silty sand and its engineering application

Through high pressure oedometer-undrained triaxial tests and dynamic triaxial tests, researches were conducted on the static and dynamic strength characteristics of the tailings silty sand of No. 4 tailings reservoir in De-xing copper mine. The Mohr-stress circles of the tailings silty sand under all the testing confining pressure show that the single line failure envelope cannot represent the strength characteristics absolutely, the double line failure envelope can express the strength properties when confining pressures are less than 1400 kPa, and the parabolic failure envelope can reflect the strength characteristics well under all the testing confining pressures. The grading curve of the tailings silty sand indicates that the grain composition is relatively homogeneous. Thus, the tailings silty sand is susceptible to liquefy under the dynamic loading. Dynamic triaxial tests of the tailings silty sand show that the tailings silty sand in deep areas has more liquefaction resistance strengths than in shallow. The possible explanation is that the structure of the deep tailings silty sand is more stable than the shallow one. The tests also reveal that the liquefaction resistance increases with the dry density when it is in the range of 1.51-1.61. The results can be used to guide the construction and ensure the safety of No. 4 tailings dam or other high tailings dams.     

Effect of solvent on the hydrothermal liquefaction of macro algae Ulva fasciata

Hydrothermal liquefaction is an attractive approach for the conversion of aquatic biomass like algae as it does not require the energy intensive drying steps. The objective of the study is to understand the effect of various solvents (H₂O, CH₃OH and C₂H₅OH) on product distribution and nature of products of hydrothermal liquefaction of macro algae Ulva fasciata (MAUF). Hydrothermal liquefaction of MAUF was performed using subcritical H₂O (300 °C) as well as supercritical organic solvents CH₃OH and C₂H₅OH (300 °C). The use of alcoholic solvents significantly increased the bio-oil yield. The bio-oil yield was 44% and 40% in case of liquefaction with CH₃OH and C₂H₅OH respectively whereas the bio-oil yield was 11% with H₂O. Use of alcoholic solvents converted the acids obtained in bio-oil to the corresponding methyl and ethyl esters. ¹H NMR data showed that use of alcoholic solvents (C₂H₅OH and CH₃OH) increased aliphatic content of bio-oil1 (ether/methanol/ethanol fraction). FTIR and SEM results showed the difference in the bio residue obtained using alcoholic solvents and H₂O. The results showed that liquefaction with supercritical alcohols is an effective way to produce functional hydrocarbons for chemical feedstock.