On the understanding and control of the spontaneous heating of dried tannery wastewater sludge

We studied the spontaneous heating of dried sludge produced by treating wastewater mainly originating from tanneries. Heating up to burning has been observed in the presence of air and moisture, starting at ambient temperature. To understand and prevent the process we combined chemical and morphological analyses (ESEM) with thermal activity monitoring in insulated vessels. Selective additions of chemicals, either to amplify or depress the reactivity, have been used to investigate and identify both the chemical mechanism causing the sludge self-heating, and a prevention or a mitigation strategy. FeS additions accelerate the onset of reactivity, while S sustains it over time. On the contrary, Ca(OH)₂, Na₂CO₃, NaHCO₃, FeCl₂, EDTA, NaClO can limit, up to completely preventing, the exothermic activity. All the experimental evidences show that the reactions supporting the dried sludge self-heating involve the Fe/S/O system. The total suppression of the reactivity requires amounts of additives that are industrially incompatible with waste reduction and economics. The best prevention requires reduction or removal of S and Fe from the dried solid matrix.     

分析样品处理中的红外线快速加热技术

本文研究了红外线快速加热样品处理工艺,红外线由钨灯产生,酸性悬浊液样品盛在玻璃容器中.该工艺的主要优点是结构简单、费用低.另外,稀酸溶液不到60s中就可加热到需要温度,且整个过程不到5min.该工艺适用于痕量分析,最初的研究是测定牛肝、苹果叶等原料中的Cu、Fe、Mn含量.结果可以达到95%的置信水平.在未经任何预处理或仅做冷冻干燥情况下,可测定铜和锰的含量,证实与用常规的微波辅助法结果一致.     

罗源湾海水与外海水的交换研究

根据多年的实测潮位资料，分析罗源湾的潮注特征，并计算出该湾的纳潮量，海水的交换率及海水半更换期。结果表明：罗源湾潮差较大，具有较大的纳潮量、大潮期间该湾的总纳潮量可达到０．９６×１０＾９ｍ＾３。就平均而言、罗源湾海水的半更换期约为１７个潮周期。     

Variations and drivers of aerosol vertical characterization after clean air policy in China based on 7-years consecutive observations

Understanding the aerosol vertical characterization is of great importance to both climate and atmospheric environment. This study investigated the variations of aerosol profiles over eight regions of interest in China after clean air policy (2013-2019) and discussed the drivers of the vertical aerosol structure, using observations from active satellite measurements (CALIPSO). From the annual variation, the amplitude of extinction coefficient profiles showed a decreasing trend with fluctuations, and the maximum was 0.21 km⁻¹ in Beijing-Tianjin-Hebei (JJJ). For regions suffered from air pollution, the variation was greatest below 0.45 km, while it was between 1-1.5 km for Sichuan Basin. The correlation coefficient between the relative humidity (RH) and the extinction coefficient indicated that the increase of RH inhibited the decrease of the extinction coefficient in the Yangtze River Delta. In most regions, the main aerosol subtypes were polluted dust and polluted continental, but they were coarser in JJJ and North West. The frequency of concurrency of dust and polluted dust aerosols decreased in JJJ, but polluted continental aerosols occurred more frequently. Further, the aerosol extinction coefficient profiles under different pollution conditions showed that it changed most during heavy pollution periods in JJJ, especially in 2017, with a significant aerosol loading between ∼700 and 1200 m. The atmospheric reanalysis data revealed that the weak convergence at low level and the divergence at high level supported the upward transport of aerosols in 2017. Overall, the differences in divergence allocation, RH, and wind filed were the main meteorological drivers.     

砷超富集植物的热解特征及其与砷含量的关系

不同热解气氛和升温速率的比较研究表明,在空气气氛条件和25℃·min-1的升温速率下,砷超富集植物的热解曲线特征明显且实验速度适中,因此,是适用于砷超富集植物的热解实验条件.在该实验条件下,不同含砷浓度的蜈蚣草(Pteris vittata L.)和大叶井口边草(P.cretica L.)的热解温度主要集中在200～500℃之间.与低砷蜈蚣草相比,高砷蜈蚣草在300℃附近热解减弱,而在450℃附近热解加剧,蜈蚣草体内的砷有促使其热解过程向高温方向偏移的趋势;而大叶井口边草体内的砷则促使其在300℃附近热分解程度加剧,而对450℃附近的热解程度影响不明显.     

确定最优轮伐期的原则及数学模型

最优轮伐期的确定是林学中最古老也是最重要的问题之一。本文试图探索在我国现阶段确定森林轮伐期所应遵循的原则。提出了五条,即:生产原则,经济原则,生态原则,社会原则以及系统原则。 讨论了简单情况下确定轮伐期的数学模型,即生产模型,经济模型,林租模型,净收益模型,土地期望价模型,土地租价模型以及推广了的模型。简单讨论了这些模型的性质及相互关系。以期引起对此问题的深入讨论。     

供水系统干旱期的水资源风险管理

把风险分析方法用于干旱期的水资源管理，给出了相应的风险、可靠性、恢复性和易损性等具体的风险指标。经实际应用表明，这些风险指标可以从不同的侧面反应干旱的真实危害程度，它较系统优化方法更简单易行，也便于水资源管理者制定和选择有效的干旱管理措施，可为水资源的规划和管理提供新的方法和途径。     

外加电场生物去污除磷的试验研究

为了探明外加电场条件下提高生物反应器去污除磷的可能性,试验中比较了普通生物反应器和外加电场生物反应器去污除磷效果的差别。结果表明:在试验条件下,外加电场生物反应器比普通生物反应器具有更高的除磷效率,并能在厌氧阶段促进磷的释放,而COD去除率提高并不明显。     

丹东市SO2污染分析

通过对大气自动监测数据和被动扩散监测数据的分析，得出丹东市SO2在采暖季早晨污染重和城市西南部污染重的时空变化规律及污染特征，确定其受城市规划建设、锅炉脱硫方式及气候条件等污染原因，并探讨了改进脱硫除尘技术、不利气象条件下减少燃煤、实施热电联产集中供热形式等防治SO2污染的途径。     

长平高速公路运营期环境影响研究

对长平高速公路原环境质量状况及运营期的环境影响进行了系统研究，提出在南河夹信了、靠山、潘家染房和腰拉拉屯4村庄尽快建设声屏障，加强公路沿线绿化工程建设，及完善管理所、服务区、收费站的污水处理设施和排水系统，以减轻高速公路运营期的环境影响。