截齿截割煤体变形破坏过程数值模拟研究

采用应变软化的模型,使用连续介质快速拉格朗日分析法(FLAC,FastLagrangianAnaly-sisofContinue)进行数值模拟计算;研究截齿截割作用下煤体变形破坏过程;分析各种工况下不同参数对煤体塑性区、最大位移、最大主应力、最大剪应力的影响。研究表明:截割力与塑性区大小成正比,位移、剪应力、主应力随截割力增大而增大;截深与塑性区大小成反比;截割角度与塑性区面积关系密切,试验用煤体最佳截割角度为5°左右;截割速度增加,塑性区面积减小;通过分析截割动态过程,得到位移矢量图及剪应变等值线图,发现截割过程中煤体的破坏是拉、剪联合作用的结果,以剪破坏为主。     

鼓泡床锅炉富氧焚烧含油污泥技术

提出了一种新型的含油污泥焚烧近零排放处理方式,即利用富氧燃烧技术焚烧含油污泥,油泥无需干化,并可以回收烟气中的CO2直接用于油田驱油,可以实现CO2的近零排放。以日焚烧200 t含油污泥为研究对象,构建了鼓泡床富氧燃烧含油污泥锅炉原则性热力系统,并分别从炉膛内密相区埋管、稀相区受热面和尾部对流受热面等方面进行了概念设计,根据鼓泡床锅炉的设计原则并结合富氧燃烧技术特点,设计了一台富氧燃烧含油污泥鼓泡床锅炉。详细介绍了鼓泡床焚烧锅炉的设计参数、结构布置,结果表明：鼓泡床富氧焚烧含油污泥系统的锅炉效率可达92.59%,富氧燃烧工况下炉膛内的换热量远远大于对流换热量。     

Evaluation of pliers’ grip spans in the maximum gripping task and sub-maximum cutting task

A total of 25 males participated to investigate the effects of the grip spans of pliers on the total grip force, individual finger forces and muscle activities in the maximum gripping task and wire-cutting tasks. In the maximum gripping task, results showed that the 50-mm grip span had significantly higher total grip strength than the other grip spans. In the cutting task, the 50-mm grip span also showed significantly higher grip strength than the 65-mm and 80-mm grip spans, whereas the muscle activities showed a higher value at 80-mm grip span. The ratios of cutting force to maximum grip strength were also investigated. Ratios of 30.3%, 31.3% and 41.3% were obtained by grip spans of 50-mm, 65-mm, and 80-mm, respectively. Thus, the 50-mm grip span for pliers might be recommended to provide maximum exertion in gripping tasks, as well as lower maximum-cutting force ratios in the cutting tasks.     

气泡尺寸对清洗固体表面油脂及颗粒污染物的影响

为明确气泡清洗技术在罐底油泥清洗中的应用情况,考察了气泡尺寸差异对固体表面清洗效果的影响。搭建了玻璃表面油污气泡清洗可视化实验装置,并设计了气泡发生器。该发生器可通过调节气液比产生多种尺寸分布的气泡。实验中产生的气泡直径分布于80~1 200 μm。研究了气泡尺寸、清洗时间、距离和角度等参数对清洗效果的影响,结果表明,在液体流量为2.5 L·min⁻¹条件下,清洗去除率随气泡尺寸的增大而提高,气泡的平均直径为800 μm时的清洗效果最好,能够将去除率从用水清洗的4.5%提高到68.3%,且当基底与水流方向为45°时的清洗去除率高于垂直或平行放置。上述结果说明,气泡撞击和破裂产生的水射流和涡流冲刷作用是主要的清洗机制。本研究结果可为高效处理油泥污染问题提供理论和实践参考,为罐底油泥清洗开拓新的解决路径。     

热解终温对含油污泥三相产物特性的影响

为实现含油污泥的资源化利用,以罐底油泥为研究对象并以油回收率为考核指标,对热解终温对油泥三相产物的影响进行了研究。结果表明,最佳热解条件是：升温速率为10 ℃·min⁻¹、载气中最佳氧气体积分数为4.2%。在400~800 ℃范围内,随着温度的升高,回收的热解油产率由16.43%提升至21.46%,后又降至14.15%;热解气产率由9.12%提升到了27.87%,热解残渣中可回收组分含量由39.1%降至16.5%。热解油中主要为轻质组分,油的品质较高;热解气中主要成分为CO₂和CO,且温度越高可燃气比例越高。对热解残渣进行电镜分析发现,渣体表面没有结焦现象,残渣表现出良好的吸附性能。本研究可为含油污泥热解处理资源化提供参考。     

A method to estimate the impact of clear-cutting on nutrient concentrations in boreal headwater streams

Large-scale forestry operations, like clear-cutting, may impair surface water quality if not done with environmental considerations in mind. Catchment and country level estimates of nutrient loads from forestry are generally based on specific export values, i.e., changes in annual exports due to the implemented forestry operations expressed in kg ha⁻¹. We introduce here a specific concentration approach as a method to estimate the impact of clear-cutting on nutrient concentrations and export in headwater streams. This new method is potentially a more dynamic and flexible tool to estimate nutrient loads caused by forestry, because variation in annual runoff can be taken into account in load assessments. We combined water quality data from eight boreal headwater catchment pairs located in Finland and Sweden, where the effect of clear-cutting on stream water quality has been studied experimentally. Statistically significant specific concentration values could be produced for total nitrogen, nitrate, ammonium, and phosphate. The significant increases in the concentrations of these nutrients occurred between 2 and 6 years after clear-cutting. Significant specific concentration values could not be produced for total phosphorus and total organic carbon with the whole dataset, although in some single studies significant increases in their concentrations after clear-cutting were observed. The presented method enables taking into account variation in runoff, temporal dynamics of effects, and the proportional size of the treated area in load calculations. The number of existing studies considering large site-specific variation in responses to clear-cutting is small, and therefore further empirical studies are needed to improve predictive capabilities of the specific concentration values.     

油气田含油污泥处理相关标准解析

通过对目前已出台油气田含油污泥处理相关标准的解析,针对标准之间存在着适用范围不一致、检测项目名称及限值不一致、检测方法不统一以及计算基础不统一等,造成油气田环保工作者和管理者认识上的混乱,对含油污泥处理技术的选用和治理市场的管理带来诸多问题。为加快促进油气田含油污泥处理减量化、资源化、无害化技术的发展,建议尽快出台有针对性、普适性强、统一的油气田含油污泥污染控制标准,确保含油污泥处理既科学合理,又经济可行;同时制定针对性强的含油污泥污染物检测方法,检测方法统一、计算公式一致,保证结果真实可靠,具有可比性。     

固定化解脂耶氏酵母处理油脂废水研究

利用海藻酸钙包埋固定的解脂耶氏酵母(Yarrowia lipolytica)分别降解以色拉油为惟一碳源和以葡萄糖为惟一碳源的污水,结果表明,在最佳处理条件下,固定化细胞在50 h内,能较好地降解废水中浓度为2 000 mg/L的色拉油和浓度为2 000 mg/L 的COD,降解率都在80%以上;固定化细胞对色拉油、COD降解效率随着时间的延长而增加、随着底物浓度的增加而下降;与未固定菌株相比,固定化细胞有着更好的储存稳定性和可重复使用性,结果进一步提示固定化解脂耶氏酵母适于含油废水以及高COD含量的生活污水处理。     

油脂高效降解菌处理含油污水的试验研究

从 4种活性污泥中驯化分离了 1 2种菌 ,考查了它们对含高浓度植物类油脂污水的降解能力 ,各菌种 72h内对CODCr超过 1 0 g/L油脂配水的去除率都接近或超过 80 % ,特别是编号为GSH -1 ,GSH -2 ,GSH -3的 3种菌的去除率分别达到 94 2 % ,92 9% ,92 5%。选用高效降解菌GSH -1进行了相关影响条件试验 ,发现表面活性剂对该菌降解油脂有一定的促进作用 ;该菌生长适宜条件为 :pH 6～ 7,温度为 3 2～4 5℃ ,油脂浓度 <2 g/L ,适宜条件下该菌在 3 0h内对餐厅实际含油污水CODCr的去除率达 86%。表明经筛选驯化所获得优势菌在高含油、含表面活性剂的条件下具有较强的去除油脂类污染物的能力。      

清洁的胡椒基T醚生产工艺的研究I,5-丙基-1,3-苯并二氧杂茂的氯甲基化废水的处理

报道了胡椒基丁醚生产中５－丙基－１，３－苯并二氧杂茂的氯甲基化的废水处理，该废水经蒸馏可回收９４％的盐酸，此酸吸收氯化氢后浓度在３６％以上，可再用于氯甲基化反应。蒸馏残液经分油、Ｆｅｎｔｏｎ试剂处理和五次生炭柱吸附后ＣＯＤＣｒ等项指标均可国家二类污染物的一级排放标准。