基于VA One船舶舱室动力设备空气噪声控制分析

目的研究舱室间壁板不同约束条件及不同敷设方式对隔声量的影响。方法用VA One建立两个舱室的统计能量分析(Statistical Energy Analysis,SEA)模型,对约束阻尼结构和自由阻尼结构的隔声性能进行分析。针对约束阻尼结构,讨论其两侧金属层厚度差对整个壁板的隔声性能的影响;对自由阻尼结构,分析金属层与阻尼层之间的相对位置对其隔声性能影响。结果约束阻尼结构隔声量A计权声压级比自由阻尼结构高。结论阻尼层厚度和壁板总厚度一定时,自由阻尼结构金属层与阻尼层之间的相对位置对实际的隔声性能并没有影响;约束阻尼结构,两侧金属层等厚敷设时,其隔声效果最优,且两侧厚度差越大隔声量越小。     

循环消化液组成对固体废物厌氧水解的影响

蔬菜花卉类废物的两相厌氧消化过程中,为加速固相有机物的水解,通过调节循环消化液中水解液与甲烷化出水的流量比(分别为0:1,1:3,1:1,3:1)改变循环消化液的组成,比较了不同流量比下循环消化液组成对固体废物厌氧水解过程的影响.结果表明,流量比为1:3 时,水解效率最高.工艺运行9d 后,TOC 和TN 的溶出量分别为162.45 和15.21mg/g, TS、VS、C、纤维素和木质素的减量率分别达到60.66%、62.88%、58.35%、49.12%和43.43%;流量比会影响厌氧酸化代谢类型,低比例促进丙酸和乳酸生成,高比例促进丁酸生成.     

Enhancement of anaerobic biodegradability of flower stem wastes with vegetable wastes by co-hydrolysis

The vegetable wastes and flower stems were co-digested to evaluate the anaerobic hydrolysis performance of difficultly biodegradable organic wastes by introducing readily biodegradable organic wastes. The experiments were carried out in batches. When the vegetable wastes were mixed with the flower stems at the dry weight ratio of 1 to 13, the overall hydrolysis rate increased by 8%, 12%, and 2% according to the carbon, nitrogen, and total solid （TS） conversion rate, respectively. While the dry weight ratio was designed as 1 to 3, there was a respective rise of 5%, 15%, and 4% in the conversion rate of carbon, nitrogen, and TS. The enhancement of anaerobic hydrolysis from the mixed vegetable wastes and flower stems can be attributed to the formation of volatile fatty acids （VFA） and nutrient supplement like nitrogen content. The maximum VFA concentration can achieve 1.7 g/L owing to the rapid acidification of vegetable wastes, loosing the structure of lignocellulose materials. The statistic bivariate analysis revealed that the hydrolysis performance was significantly related to the physical and biochemical compositions of the feeding substrate. Especially, the soluble carbon concentration in the liquid was significantly positively correlated to the concentration of nitrogen and hemicellulose, and negatively correlated to the concentration of carbon and lignocellulose in the feeding substrate, suggesting that the regulation and control of feedstock can have an important influence on the anaerobic hydrolysis of organic wastes.     

垃圾填埋场覆土层Ⅱ型甲烷氧化菌的群落结构

采用基于16S rDNA 的变性凝胶梯度电泳(DGGE)技术研究了生活垃圾卫生填埋场和生物反应器填埋场覆土中Ⅱ型甲烷氧化菌群落结构,比较了不同填埋操作方式对Ⅱ型甲烷氧化菌的影响.结果表明,覆土铺有HDPE 膜、无填埋气体渗入的填埋覆土中未发现Ⅱ型甲烷氧化菌;而有填埋气体渗入时,进行渗滤液亚表面灌溉的生物反应器填埋场,无论是否同时进行层内回灌,其覆土中均检测到甲烷孢囊菌(Methylocystis).卫生填埋场填埋龄长达5a 的填埋覆土中发现了甲基弯菌(Methylosinus),填埋龄较低的填埋场覆土中未发现II 型甲烷氧化菌.渗滤液亚表面灌溉及长时间填埋气体驯化能促进Ⅱ型甲烷氧化菌的生长.有机质等营养物质丰富而NH4+-N浓度较低的填埋覆土有利于Ⅱ型甲烷氧化菌的生长.     

酸化大豆蛋白废水的厌氧处理

对有机质浓度高,成分单一,蛋白质、总氮浓度较高,易酸化,且已酸化程度较高的大豆蛋白废水,确定以新型内循环厌氧反应池为主的处理工艺,在原废水ρ(COD)为11809~15040mg/L时,总出水浓度192~350mg/L,去除率达到96.2%~97.5%。新的内循环厌氧反应池具有高度小、结构简单、污染物去除率高的特征,COD运行负荷达6.0~7.5kg/(m3.d),COD去除率达88%~93%。当COD运行负荷5.0~7.0kg/(m3.d)时,该池内循环管道形成了连续的较强内回流。     

粉煤灰对垃圾填埋场黄土垫层的改性试验

通过击实、渗透试验得到粉煤灰改性-黄土的最佳配比为10%。对压实黄土和压实粉煤灰改性-黄土,分别用清水和渗滤液进行室内渗透试验,结果表明:渗滤液在压实粉煤灰改性黄土中的渗透系数≤1.0×10-7cm/s,在压实黄土中的渗透系数≤1.0×10-5cm/s,前者可作为填埋场防渗垫层,后者可作为填埋场防渗保护垫层。对COD、NH3-N的去除效果前者优于后者。     

Relation of lead adsorption on birnessites with different average oxidation states of manganese and release of Mn^2＋/H^＋/K^＋

The characteristics of Pb2+ adsorption on the surface of birnessites with different average oxidation states (AOS) of Mn, synthesized under acidic and alkali conditions, were investigated. The results indicated that the amount of adsorbed Pb2+ increased with the increase of Mn AOS in birnessites. The amount of Pb2+ adsorbed positively correlated with the amount of released Mn2+, H+, and K+ (r = 0.9962 > 0.6614, n = 14, α = 0.01). The released Mn2+, H+, and K+ were derived mostly from the corresponding catio...     

CASS工艺脱氮影响因素分析

针对CASS工艺脱氮的效果不够理想、效率不高、出水不够稳定的现象,对脱氮的主要影响因素曝气时间、DO、温度、λ进行了生产性试验研究,分析结果表明,曝气时间3h,D02．5mg／L是本污水厂最合理的参数控制值,曝气时间3h时NH3-N和TN的平均去除率分别为89．7％和59．7％,D02．5mg／L时NH3-N和TN的平均去除率分别为94．5％和71．3％,脱氮效果良好;温度对脱氮的效果有很明显的影响,春季的脱氮效果明显好于冬季;脱氮效果随冲水比的增高而降低,但出水均达标说明CASS工艺有良好的抗冲击负荷的能力。     

船舶塑料垃圾热解特性及动力学分析

利用热重分析(TGA)研究船舶塑料垃圾在不同升温速率和不同气氛下的热解特性,并得到了热解动力学参数。结果表明,船舶塑料垃圾的热解过程主要有3个阶段,比一般塑料热解复杂;随着升温速率增大,最大热解速率和最大热解速率温度等热解特性参数也增大,反应变得更剧烈;N2/CO2比为4∶1时,热解反应进行得最完全,固体残留率最少。动力学分析表明,采用3个连续一级反应模型能很好地拟合实验数据;不同的升温速率和气氛比对反应各阶段活化能均有不同程度的影响。