常温条件下CAST工艺亚硝酸型硝化的实现及特性

采用循环式活性污泥法(CAST)处理模拟生活污水,通过控制曝气量,使反应器中DO在0.13～0.74 mg/L之间,在常温下快速实现亚硝酸型硝化,然后增大曝气量使反应器内DO在0.7～3.36 mg/L之间,控制曝气时间1.5 h,考察系统内亚硝酸型硝化的维持情况。结果表明,14℃条件下,通过先控制低溶解氧浓度再控制曝...     

固定化微生物法去除模拟渗滤液中氨氮的研究

采用固定化微生物曝气生物滤池（I-BAF）技术成功处理了模拟垃圾渗滤液,探讨了pH和溶解氧（DO）对系统脱氮性能的影响。结果表明,固定化微生物曝气生物滤池反应系统启动迅速,运行稳定,可以有效去除模拟垃圾渗滤液中的有机物和氨氮,其去除率分别达到97.1%和99.9%。在pH为7.5～8.5之间,DO 4.0 mg/L左右的条件下对模拟垃圾渗滤液中氮的去除最为有利,同步硝化反硝化效率以及总氮去除率均达到最高,分别为96.2%和94.3%。这主要是由于I-BAF系统中大孔载体提供了厌氧-兼氧-好氧的微环境,使硝化和反硝化反应在同一个反应器内发生,共同作用实现模拟垃圾渗滤液中总氮的去除。     

不同氮磷比对多年生水生植物生长特性影响的研究

从氮、磷等植物生长的环境因子出发,研究了高低氮磷营养水平下,不同氮／磷比例的富营养化水体对聚草（Myriophyllum spicatum）、黄花水龙（Jussiaea stipulacea Ohwi）、喜旱莲子草（Alternanthera philoxeroides）生长特性的影响。结果表明,聚草在氮磷比2：1时生物量最大,且生物量在高浓度水平处理明显大于低浓度水平处理（P〈0．01）;黄花水龙在氮磷比10：1～20：1时生物量最大,高低浓度水平处理问生物量无显著性差异;喜旱莲子草在较高氮磷比20：l～40：1时生物量最大,高浓度水平处理时生物量显著性高于低浓度水平处理（P〈0．05）。在低浓度水平处理时,氮为黄花水龙和喜旱莲子草生长的主要限制因子,磷为聚草生长的主要限制因子,且喜早莲子草叶绿素增长期较其他处理提前,而黄花水龙的叶绿素变化在高低营养水平下差异不显著。营养盐水平对聚草茎长和生物量的影响较对黄花水龙和喜旱莲子草的影响明显。     

餐厨垃圾厌氧消化中硬脂酸钙的形成及作用

在稳定运行的餐厨垃圾单相厌氧消化体系中,出现白色颗粒状物质,且随着负荷的提高,其数量和粒径不断增加。利用能谱技术分析白色颗粒的元素组成,结合傅里叶红外光谱和13C核磁共振技术分析白色颗粒中的官能基团。经过研究分析认为,该白色颗粒的主要成分为长链羧酸钙盐,具体为硬脂酸钙。同时,对其形成过程进行了分析。该物质的形成对餐厨垃圾中油脂的去除提供了新的思路和途径。     

Emergy analysis of the recycling options for construction and demolition waste

Construction and demolition (C&D) waste is becoming a major contributor to environmental pollution. In Shanghai, China, the quantity of C&D waste is 2.11E+07 t/yr, which accounts for 45% of the total quantity of solid waste. There has been a growing promotion of recycling C&D waste as an effective way to solve this waste problem. However, the evaluation of the efficiency of recycling C&D waste as a potential source of resources is largely based on traditional economic analysis. The economic analysis emphasizes money instead of the harmony between economic benefit and environmental effects. There is a need for a new strategic approach to investigate the efficiency of recycling C&D waste to achieve the integration between economic, social and environmental effects. Emergy theory can be employed to analyze different recycling options for C&D waste. With reference to the Chinese construction industry, this paper demonstrates that the close-loop recycling option is better than the open-loop recycling option for C&D waste in terms of the integration of social, environmental and sustainable aspects. To evaluate different technology solutions for C&D waste recycling, the emergy theory and method is not limited to a cost-benefit balance but can include economic, social, environmental and sustainable effects.     

Zinc accumulation and synthesis of ZnO nanoparticles using Physalis alkekengi L

A field survey and greenhouse experiments were conducted using Physalis alkekengi L. to investigate strategies of phytoremediation. In addition, ZnO nanoparticles were synthesized using P. alkekengi. P. alkekengi plants grew healthily at Zn levels from 50 to 5000 mg kg⁻¹ in soils. The plants incorporated Zn into their aerial parts (with mean dry weight values of 235-10,980 mg kg⁻¹) and accumulated biomass (with a mean dry weight of 25.7 g plant⁻¹) during 12 weeks. The synthesized ZnO nanoparticles showed a polydisperse behavior and had a mean size of 72.5 nm. The results indicate that P. alkekengi could be used for the remediation of zinc-contaminated soils. Moreover, the synthetic method of synthesizing ZnO nanoparticles from Zn hyperaccumulator plants constitutes a new insight into the recycling of metals in plant sources.     

微波诱导Fe2O3/沸石负载型催化剂催化氧化焦化废水的研究

以天然沸石为载体,采用尿素均匀沉淀法制备了Fe2O3/沸石负载型催化剂(简称负载催化剂),研究其在微波辐射下对焦化废水的处理效果,探讨了负载催化剂投加量、微波辐射功率、微波辐射时间等因素对处理效果的影响,并考察了负载催化刑的重复使用性能.结果表明,天然沸石、于350℃焙烧得到的负载催化刑和于550℃焙烧得到的负载催化剂...     

微波-过氧乙酸联合作用处理剩余污泥的研究

采用微波-过氧乙酸(PAA)联合作用处理剩余污泥,考察了微波辐照时间、微波功率、PAA投加量对剩余污泥分解效果的影响.同时以单独微波作用为对比,考察了微波-PAA联合作用下剩余污泥性质的变化.结果表明,当微波功率为600 W,PAA投加量为0.24 g/g(以干质量SS计)时,微波辐照60 s后剩余污泥分解率可达35%...     

Effects of Preparation Parameters on Properties of Soy Protein-Based Fiberboard

The effects of manufacturing parameters on mechanical properties of medium density fibreboard (MDF) bonded with modified soy protein-based glue were studied to find an appropriate manufacture technology. Physical properties of MDF made with different amount of wax emulsion were measured. Results indicated that water repellent had no obvious influence on physical properties of soy protein-based MDF boards. The fiberboards bonded with soy protein-based glue showed stronger water resistance properties than those bonded with urea–formaldehyde (UF) resins. Furthermore, the soy protein-based MDF boards had good quality [25.2% 24 h soak thickness swell (TS), 29.9 MPa modulus of rupture (MOR), 3130 MPa modulus of elasticity (MOE)], which met requirements of Chinese national standard. Practical processing parameters were obtained by orthogonal experiment, i.e., glue content 8.0%, hot-press temperature 200 °C, and hot-press time 150 s.     

不同诱导条件对结晶产物形貌特征的影响

在流化床反应器中,以含铜废水为处理对象,重点考察了诱导条件改变对结晶系统运行效率及结晶产物形貌特征的影响。结果表明,进水200 mg/L,进药比([Cu2+]/[CO2-3])1∶1.2,p H为10.2的条件下,铜离子去除率可接近100%,诱导晶种表面平滑,诱导颗粒生长成致密杆状晶体结构,以碳酸盐为沉淀剂的诱导结晶系统依赖于体系的p H,高p H体系下发生的共结晶现象是影响系统运行的主要原因;随着进药摩尔比的增加,结晶产物由短杆状向球状转化,晶体机械强度显著降低大量破碎,影响出水水质;进药比1∶1.2,p H为11的条件下,含铜废水浓度为500 mg/L时,系统去除率可达95%以上,微晶产率低于5%。