草制浆造纸中段废水处理及回用技术分析研究

中段废水是制浆造纸工业的主要污染源之一,从工程设计的角度出发,对草制浆造纸中段废水处理及回用提出一套可行适用的工艺方案;对主要工艺环节参数、设备备有说明,以供同行借鉴.     

用高效分散剂碳化法从煤矸石中制备超细氢氧化铝粉体

利用煤矸石为原料制备超细氢氧化铝粉体.采用高温煅烧活化煤矸石,利用C2S晶相转变制备煤矸石自粉化料,用8%Na2CO3溶液从煤矸石自粉化料中以NaAlO2形式提取铝组分,用高效分散剂碳化法制备超细氢氧化铝粉体.研究了高效分散剂碳化法制备高纯超细氢氧化铝粉体的影响因素,找出了高效分散剂碳化法制备超细氢氧化铝粉体的最佳条件,制备出了平均粒度＜100nm、纯度＞99.9%的氢氧化铝,为煤矸石的高价值利用开辟了一条新的途径.     

Formation of organochlorine compounds in kraft pulp bleaching processes

The most abundant volatile organochlorine compounds (VOCCs), trichloroacetic and dichloroacetic acids and AOX, were determined in bleaching effluent and waste water from three kraft pulp mills during ClO₂ bleaching. 0.6–7.7 g of VOCCs per ton bleached pulp were formed, the most abundant being chloroform and dichloroacetic acid methyl ester. Most of the VOCCs were removed during treatment, and it was estimated that 2–30 t of VOCCs would be removed annually from activated sludge treatment plants in Finnish kraft pulp mills using elemental chlorine free bleaching, most likely by volatilization. Dichloroacetic acid was formed in considerably higher amounts than trichloroacetic acid, and both compounds were removed effectively during treatment. The formation of all organochlorine compounds decreased considerably when non-chlorinated bleaching was employed.     

Degradation of benomyl, picloram, and dicamba in a conical apparatus by zero-valent iron powder

Reduction of some pesticides (benomyl, picloram, and dicamba) was studied in an aerobic batch conical pilot system to investigate the disappearance of these pesticides on contact with iron powder (20 g/l, 325-mesh). Aqueous buffered solutions of the compounds were added to the system followed by zero-valent iron powder (ZVIP), and the decline in the pesticide concentrations was monitored over time. HPLC analyses show a complete disappearance of picloram (1.20 mg/l) after 20 min of reaction. Benomyl (1.00 mg/l) and dicamba (1.25 mg/l) disappear after 25 and 40 min, respectively. The t₅₀ values ranged from 3 to 5.5 min, and were about slightly less than the t_1/2 values reported when the log of the relative HPLC peak area was plotted versus time, where the relative peak area was calculated by dividing the measured peak area by the initial peak area. Pathways for the degradation of the studied pesticides by ZVIP are proposed.     

进口粉末涂料物料固体废物鉴别方法的建立

粉末涂料生产过程中产生的固体废物属于我国禁止进口的固体废物,进口粉末涂料物料是否属于固体废物仅凭借口岸监管人员的常识和肉眼观察无法确定,需要通过专门的固体废物鉴别确定,但迄今为止没有粉末涂料物料的固体废物鉴别标准、规范或方法,因此,非常有必要建立进口粉末涂料物料的固体废物鉴别方法.在对多例进口粉末涂料物料固体废物鉴别实例总结归纳的基础上,建立了其固体废物鉴别方法:①确定物料的自然属性,包括利用傅里叶变换红外光谱（FTIR）分析主要成分;利用低温电炉和马弗炉得到有机物和无机物的大概质量分数;采用X射线荧光光谱（XRF）分析灼烧残渣的主要成分及其质量分数.②确定物料的产生来源,判断出物料是否属于粉末涂料产品,具体指通过肉眼观察物理形态和杂质;测量粉末部分的粒度分布;分析粉末部分的容器中状态、粒径分布、涂膜外观和耐冲击性等HG/T 2006—2006《热固性粉末涂料》中要求的指标.③确定物料的固体废物属性,即根据GB 34330—2017《固体废物鉴别标准通则》中的相关条款,得出物料的固体废物鉴别结论.利用该方法对海关怀疑为固体废物的以粉末涂料产品名义申报进口的两种物料进行了固体废物鉴别,鉴别结果显示,两种物料均产生于粉末涂料产品生产过程,分别为不合格粉或者过期粉和超细粉,均属于我国禁止进口的固体废物,显示所建立的固体废物鉴别方法可行,可为进口粉末涂料生产过程中产生的物料的固体废物鉴别和监管提供参考.      

双基球扁药工艺优化仿真研究

目的优化双基球扁药成球工艺参数,解决由于目前双基球扁药理论研究不充分、控制模型不明确、生产工艺参数调控依靠人工经验所导致的药品成球后直径、弧厚偏差大的问题。方法利用BP神经网络在处理复杂非线性映射问题上的强大的能力,对成球关键工艺参数与成球质量指标进行建模,并应用成球工艺过程仿真数据对其进行训练,将训练得到的BP神经网络模型用于优化成球工艺参数。同时利用仿真数据进行检验模型的可靠性。结果训练后BP神经网络均方误差为0.001,成球直径误差率为1.27%,成球弧厚误差率为2.08%,成球质量参数误差均很小,可以满足工艺要求。结论该BP神经网络模型具有较高精度,适用于含能材料工艺优化,提出的成球工艺优化方法能有效降低成球试制成本,缩短生产周期。     

砂岩和花岗岩岩石表层光释光信号晒退速率对比及测年意义

光释光信号已被成功地应用于岩石表层暴露、埋藏年龄的测定以及判别岩石经历的曝光和埋藏历史。本文选择红褐色石英砂岩和灰白色黑云母花岗岩进行了岩块和岩片晒退不同时间的实验研究,结果显示:岩石光释光信号(IR_(50);IRSL)可被光(阳光和全光谱模拟太阳灯灯光)快速晒退。曝光一定时间后,岩块表层一定深度的光释光信号可以归零,且随曝光时间的延长,自暴露面向内的光释光信号归零深度也随之加深。砂岩和花岗岩光晒退对比实验结果显示:与深色砂岩相比,浅色的花岗岩有更高的光释光信号晒退速率。实验同时揭示:本研究所采用的红外光源激发获得的光释光信号来自岩片(1.2 mm)表层一定深度,并没有完全穿透该岩片。该研究为了解不同岩性岩石的光释光信号晒退速率、测年对象的合理选择以及岩石样品采集、前处理和测试等提供了实验数据支持。     

2株漂白废水高效降解菌的选育

用含氯漂白废水驯化城市污水处理厂的好氧污泥 ,从中分离出两株高效去除有机氯的菌 ,并对其适应条件进行了研究。结果表明 ,当pH为 7.0、废水浓度为 5 0 %、加入 0 .4g/L葡萄糖、2mL菌液时 ,处理效果较好 ,有机氯的去除率最高可达 74 .8%。     

Experimental design of Fenton and photo-Fenton reactions for the treatment of cellulose bleaching effluents

Multivariate experimental design was applied to the treatment of a cellulose conventional bleaching effluent in order to evaluate the use of the Fenton reagent under solar light irradiation. The effluent was characterised by the general parameters total organic carbon (TOC), chemical oxygen demand and color, and it was analysed for chlorinated low molecular weight compounds using GC–MS. The main parameters that govern the complex reactive system: Fe(II) and H₂O₂ initial concentration, and temperature were simultaneously studied. Factorial experimental design allowed to assign the weight of each variable in the TOC removal after 15 min of reaction. Temperature had an important effect in the organic matter degradation, especially when the ratio of Fenton reagents was not properly chosen. Fenton reagent under solar irradiation proved to be highly effective for these types of wastewaters. A 90% TOC reduction was achieved in only 15 min of treatment. In addition, the GC–MS analysis showed the elimination of the chlorinated organic compounds initially detected in the studied bleaching effluents.     

Use of Water Clarity to Monitor the Effects of Climate Change and other Stressors on Oligotrophic Lakes

We present evidence from studies oflakes in Killarney Park, Ontario, Canada that waterclarity is a key variable for monitoring theeffects of climate change, high UV exposure andacidification. In small oligotrophic lakes, thesestressors affect water clarity primarily byaltering the concentration of DOC in lake water. Clear lakes (<2 mg L^-1 DOC) proved to be highlysensitive indicators of stressors, exhibiting largethermal and optical responses to small changes inDOC. Extremely clear (<0.5 mg L^-1 DOC) acidic lakesshowed the effects of climate change and solarbleaching in recent decades. These lakes becamemuch clearer even though they were slowlyrecovering from acidification.