鲕状赤铁矿选矿废水处理研究

针对鲕状赤铁矿选矿废水特征,提出静沉一混凝一氧化的处理工艺,并对混凝和氧化工艺条件进行筛选和优化。实验表明,自然沉降能够去除大部分悬浮物、COD和金属离子;聚合氯化铝PAC对鲕状赤铁矿选矿废水混凝沉降比聚合氯化铝铁、硫酸铝和氯化钙效果更好;混凝过程与搅拌强度、搅拌时间、pH值和沉降时间有关;空气曝气氧化处理混凝后水样能进一步有效降低COD值,且COD的去除效果受空气曝气流量、曝气时间和静置氧化时间的影响。通过静沉一混凝一氧化的工艺处理后的出水水质能达到国家排放指标。     

某鲕状赤铁矿选矿试验研究

针对微晶赤铁矿与绿泥石、粘土、胶磷矿等构成的鲕状赤铁矿矿石的性质,采用磁选-酸浸联合工艺,当原矿中含Fe为48.89％,含P为0.65％时,可获得Fe品位为55.71％,回收率为60.59％的铁精矿,铁精矿中P的含量降至0.10％.     

Changes of Molecular Glycerophospholipid Species in Plasma and Red Blood Cells During Docosahexaenoic Acid Supplementation

Docosahexaenoic acid (DHA) status is related to health and disease risk. DHA status is mainly determined by dietary DHA intake, since endogenous synthesis of DHA is limited. We aimed to investigate the changes of different molecular glycerophospholipid species containing DHA in plasma and red blood cells (RBC) in response to increased DHA intake. Thirteen healthy adults had their diet supplemented with 510 mg DHA/day for 29 days. Fasted blood samples were taken at 11 time points and glycerophospholipid species were analyzed by liquid chromatography mass spectrometry. In plasma, percentages of glycerophospholipid species containing DHA increased significantly by 64–104 % relative to baseline values during supplementation, but the relative distribution between species was not markedly altered. In RBC, phosphatidylcholine (PtdCho) species containing DHA increased to a similar extent as in plasma, while phosphatidylethanolamine and phosphatidylserine species with DHA increased by only 12–25 %, respectively, which was significantly different compared to PtdCho species (p < 0.01). Despite the high increase, the contribution of DHA PtdCho species to total DHA remained minor (14 % after supplementation). In conclusion, DHA supplementation does not alter the relative distribution of DHA among glycerophospholipid species in plasma. A majority of PtdCho species are rapidly exchanged between plasma lipoproteins and RBC membrane lipids, while there is a minor exchange of phosphatidylethanolamine and phosphatidylserine species.     

Investigations in an external-loop airlift photobioreactor with annular light chambers and swirling flow

Photosynthetic microorganisms could serve as valuable compounds, but also for environmental applications. Their production under controlled conditions implies to design specific reactors, named photobioreactors, in which light supply is the main constraint. This paper was devoted to an original external-loop airlift photobioreactor (PBR) with annular light chambers in which a swirling motion was induced. The aim was to characterize this novel geometrical configuration in terms of gas-liquid hydrodynamics, and to test its potentiality for algal cultures. This PBR consisted of two identical columns connected by flanges defining tangential inlets, each column being made of two transparent concentric tubes (6 L in liquid volume, 50 m⁻¹ in specific illuminated area). Firstly, the global flow characteristics (circulation and mixing times) were determined by a tracer method and modelled by an axial dispersed plug flow with complete recirculation (Péclet number). By means of a double optical probe, both local and global time-averaged parameters of the gas phase were measured, namely void fraction, bubble velocity, frequency and size. The gas-liquid mass transfer were also characterized, in tap water and in culture medium, by measuring overall volumetric mass transfer coefficients. In a second time, cultures of the microalga Chlamydomonas reinhardtii were run in batch mode. The variations of biomass concentration and pigment content with time from inoculation were successfully obtained. All these findings highlighted: (i) some significant differences in terms of gas-liquid hydrodynamics between the present PBR and the usual airlift systems, (ii) the interest of this configuration for algal cultures, even if complementary studies and technological improvements are still required for definitively validating its scale-up.     

藻华的控制与开发利用研究

有害藻华不仅威胁工业、渔业、旅游业及生态系统,而且通过产生细菌毒素影响公共健康。微藻生物质富含蛋白质、核酸和脂质等,通过加工可用作肥料、动物饲料和生物燃料。分析了藻华的成因与危害,地表水中氮磷的主要来源及控制技术,探讨了藻类的利用方法和技术手段。     

四川华弹鲕状赤铁矿选矿试验研究

四川凉山州华弹鲕状赤铁矿类似宣龙式鲕状赤铁矿,该矿床鲕粒较大,含磷较低。该鲕状赤铁矿以脉石杂质为鲕粒核心,以赤铁矿与脉石相间或混杂的同心层组成鲕粒,赤铁矿与脉石界线不分明,脉石与赤铁矿分离非常困难,矿石属易破易磨极难选铁矿石。针对该矿性质特点,对华弹鲕状赤铁矿进行选矿探索试验研究,提出了在合理的磨矿细度条件下,采用重-磁联合工艺流程,最终可获得铁品位55.07%,产率43.69%,回收率66.27%的选别效果,为华弹鲕状赤铁矿开发利用提供了新的技术依据。      

微细粒嵌布难选鲕状赤铁矿现状研究及展望

鲕状赤铁矿因其微细粒嵌布、结构复杂等特点,一直被认为是世界选矿难题。本文主要研究了其在我国的利用现状,以及强磁选-反浮选、絮凝-强磁选、磁化焙烧-磁选等传统基础选别技术,并讨论了一种高效选别技术——深度还原,对鲕状赤铁矿的选别具有很重要的现实意义。     

助熔剂降低赤褐铁矿深度还原温度的试验研究

针对目前难选铁矿深度还原能耗高、成本高难于工业化的现状,进行了添加助熔剂降低深度还原温度的试验。通过还原剂种类、用量、还原合适温度的试验研究,得出用Na2CO3为助熔剂,原矿∶无烟煤∶Na2CO3=6∶3∶2,深度还原温度降到1050℃时,可将原矿品位为35.23%的贫细鲕状赤铁矿,通过深度还原-磁选,获得铁精矿品位93.04%、回收率94.53%的较好指标。     

The extended Kalman filter for forecast of algal bloom dynamics

A deterministic ecosystem model is combined with an extended Kalman filter (EKF) to produce short term forecasts of algal bloom and dissolved oxygen dynamics in a marine fish culture zone (FCZ). The weakly flushed FCZ is modelled as a well-mixed system; the tidal exchange with the outer bay is lumped into a flushing rate that is numerically determined from a three-dimensional hydrodynamic model. The ecosystem model incorporates phytoplankton growth kinetics, nutrient uptake, photosynthetic production, nutrient sources from organic fish farm loads, and nutrient exchange with a sediment bed layer. High frequency field observations of chlorophyll, dissolved oxygen (DO) and hydro-meteorological parameters (sampling interval Δt = 1 day, 2 h, 1 h, respectively) and bi-weekly nutrient data are assimilated into the model to produce the combined state estimate accounting for the uncertainties. In addition to the water quality state variables, the EKF incorporates dynamic estimation of algal growth rate and settling velocity. The effectiveness of the EKF data assimilation is studied for a wide range of sampling intervals and prediction lead-times. The chlorophyll and dissolved oxygen estimated by the EKF are compared with field data of seven algal bloom events observed at Lamma Island, Hong Kong. The results show that the EKF estimate well captures the nonlinear error evolution in time; the chlorophyll level can be satisfactorily predicted by the filtered model estimate with a mean absolute error of around 1-2 μg/L. Predictions with 1-2 day lead-time are highly correlated with the observations (r = 0.7-0.9); the correlation stays at a high level for a lead-time of 3 days (r = 0.6-0.7). Estimated algal growth and settling rates are in accord with field observations; the more frequent DO data can compensate for less frequent algal biomass measurements. The present study is the first time the EKF is successfully applied to forecast an entire algal bloom cycle, suggesting the possibility of using EKF for real time forecast of algal bloom dynamics.     

层序地层学在碳酸盐岩鲕滩储层预测中的应用研究

碳酸盐岩礁滩相带是油气的重要储集场所,近年来逐步成为我国油气勘探工作的重点。四川普光特大气田的发现为我国碳酸盐岩生物礁滩气藏的勘探起了重要的指导作用。沉积相带在碳酸盐岩礁潍的分布起到了至关重要的作用。研究从层序地层、地震地层学与地震属性分析的角度对四川一些地区的鲕粒滩相的识别进行总结。