光催化技术在功能性空气过滤材料中的应用研究

针对目前气态污染物和气溶胶态污染物对人们生活健康产生的巨大危害,论述了目前国内外光催化技术在功能性空气过滤材料中的研究,阐述了光催化技术和纤维过滤技术的基本原理,并对光催化剂在纤维上的负载和应用做了详细介绍,最后提出了该领域可能的发展方向。     

复三维电极-生物膜反应器脱除饮用水中硝酸盐的试验研究

研究了连续流复三维电极-生物膜反应器在不同电流、温度和pH条件下的反硝化性能.结果表明,在电流从0mA增加至100mA的过程中,NO3--N去除率随电流增大而升高;电流为100mA时NO3--N去除率最高,达到了73.8%,出水NO3--N浓度为8.27mg.L-1;电流高于100mA时,NO3--N去除率略有下降.电流从0mA增加至150mA的过程中,NO2--N积累量先增加后减少;电流为60mA时NO2--N的积累最为严重.温度为31～35℃时,反硝化效果较好,出水NO3--N浓度低于10mg.L-1;温度为35℃时,NO3--N去除率最高,达到了85.5%.pH值为7.2～8.2时,反硝化效果较为理想,出水NO3--N浓度在10mg.L-1以下,NO2--N浓度低于1mg.L-1.该反应器具有较好的pH缓冲性能,进水pH从5.5上升至9.0的过程中,其出水pH可维持在7.6～8.2,NO3--N去除率在59.6%～80.2%.此外,电流、温度和进水pH还对氨氮的生成量和总磷的去除产生明显影响.通过复三维电极-生物膜反应器与纯电化学反应器的对比试验,对氨氮产生和总磷去除的可能原因进行了分析和探讨.     

三阶段控温堆肥过程中接种复合微生物菌群的变化规律研究

接种复合微生物是提高堆肥效率的主要方法之一,但由于堆料中土生微生物的竞争,较高浓度的土生微生物浓度会抑制接种微生物的长生繁殖.实验表明:当堆料中土生微生物初始浓度为4×10⁸CFU/g时,所接种的微生物不增殖,且随着堆肥的进行,浓度下降很快;而非接种微生物增殖很快,最高浓度可达10¹⁰CFU/g.当土生微生物浓度降低至4×10⁵个/g,接种微生物增殖较快,最高达10¹¹CFU/g.因此,本文利用堆肥自身产热和少许外来热源加热的三阶段控温法进行堆肥.使堆温在4 h内迅速升到70℃以上,并维持8 h,从而使土生微生物浓度降至4×10⁵个/g以下,并起到软化堆料,便于微生物降解的目的.待温度冷却至35℃～45℃时,接种复合微生物,使其快速生长繁殖,数量从10⁸ CFU/g上升到10¹¹CFU/g(干样品),且接种微生物以非接种做生物保持优势地位,从而快速分解垃圾中的有机物.由于在最终产品中含有大量接种有益微生物,可利用其作为菌肥进行回流接种堆肥,以增加堆料中接种微生物数目、改善堆肥微环境、节约菌剂用量、缩短堆肥发酵周期和降低堆肥成本.但利用接种微生物堆肥产品作为菌肥反复接种时,随着反复次数的增加,非接种微生物高浓度繁殖;接种微生物和非接种微生物浓度比约为1:3(反复接种5次),浓度情况发生了逆变.因此,回流菌肥反复接种5次后,接种菌剂基本上就不再起作用了.     

城市固体有机废物堆肥实验装置设计

根据城市固体有机废物的特点和性质 ,设计了一种堆肥的实验装置 ,该设计包括空间结构设计、通风系统设计和搅拌系统设计。空间结构设计的特点是小型的、用于实验室研究的、仓式动态好氧结构 ;通风系统的设计则是以供氧、散热和去除水分所需通风量为基础 ;搅拌系统设计包括搅拌器的结构设计和所需动力设计     

水泥、粉煤灰及DTCR固化/稳定化重金属污染底泥

采用水泥、粉煤灰及有机硫稳定剂DTCR固化/稳定化处理重金属污染的底泥,考察固化体的抗压强度及重金属浸出毒性,确定了底泥固化/稳定化的最佳工艺条件。结果表明:仅用水泥固化/稳定化重金属污染底泥,固化体抗压强度随水泥用量的增加而上升,重金属浸出浓度则下降,当水泥∶干底泥质量比为0.6∶1.0时,固化体7 d抗压强度能达到0.99 MPa的标准值;进一步研究发现,水泥∶粉煤灰∶干底泥质量比为0.54∶0.06∶1.0时,重金属浸出浓度有所上升,但7 d及28 d抗压强度仍能分别达到1.2 MPa和2.8 MPa;加入DTCR后,当水泥∶粉煤灰∶DTCR∶干底泥质量比为0.54∶0.06∶0.012∶1.0时,固化体7 d及28 d抗压强度分别为1.1 MPa和2.1 MPa,醋酸缓冲溶液法浸出的Cd、Pb、Zn和Cu浓度分别为0.102、0.189、0.180和0.032 mg/L。     

固体废弃物资源化利用评价体系及研究方法

从经济、社会政策和环境影响三个角度,运用层次分析法、模糊决策理论和多目标分析3种评价方法以及矩阵、德尔斐法和混合优序图等数学工具,分别对上海市固体废弃物资源化利用所采用的不同方案进行全面综合评价,不同评价方法的研究结果具有一致性,均表明环境影响是相对最重要的影响因素,固体废弃物双向分离系统的建立是最优化的固体废弃物资源化利用方案,也是今后上海固体废弃物资源化利用研究的重点以及努力发展的方向.     

Effect of nitrification inhibitor DMPP on nitrogen leaching, nitrifying organisms, and enzyme activities in a rice-oilseed rape cropping system

DMPP （3,4-dimethylpyrazole phosphate） has been used to reduce nitrogen （N） loss from leaching or denitrification and to improve N supply in agricultural land. However, its impact on soil nitrifying organisms and enzyme activities involved in N cycling is largely unknown. Therefore, an on-farm experiment, for two years, has been conducted, to elucidate the effects of DMPP on mineral N （NH4^＋- N and NO3^--N） leaching, nitrifying organisms, and denitrifying enzymes in a rice-oilseed rape cropping system. Three treatments including urea alone （UA）, urea ＋ 1% DMPP （DP）, and no fertilizer （CK）, have been carded out. The results showed that DP enhanced the mean NH4^＋-N concentrations by 19.1%-24.3%, but reduced the mean NO3^--N concentrations by 44.9%-56.6% in the leachate, under a two-year rice-rape rotation, compared to the UA treatment. The population of ammonia oxidizing bacteria, the activity of nitrate reductase, and nitrite reductase in the DP treatment decreased about 24.5%-30.9%, 14.9%-43.5%, and 14.7%-31.6%, respectively, as compared to the UA treatment. However, nitrite oxidizing bacteria and hydroxylamine reductase remained almost unaffected by DMPP. It is proposed that DMPP has the potential to either reduce NO3^--N leaching by inhibiting ammonia oxidization or N losses from denitrification, which is in favor of the N conversations in the rice-oilseed rape cropping system.     

Effect of inorganic carbon on anaerobic ammonium oxidation enriched in sequencing batch reactor

The present lab-scale research reveals the enrichment of anaerobic ammonium oxidation microorganism from methanogenic anaerobic granular sludge and the effect of inorganic carbon(sodium bicarbonate)on anaerobic ammonium oxidation.The enrichment of anammox bacteria was carried out in a 7.0-L sequencing batch reactor(SBR)and the effect of bicarbonate on anammox was conducted in a 3.0-L SBR.Research results,especially the biomass,showed first signs of anammox activity after 54 d cultivation with synthetic w...     

Enhanced adsorption of hexavalent chromium by a biochar derived from ramie biomass (<Emphasis Type="Italic">Boehmeria nivea</Emphasis> (L.) Gaud.) modified with β-cyclodextrin/poly(L-glutamic acid)

This paper explored biochar modification to enhance biochar’s ability to adsorb hexavalent chromium from aqueous solution. The ramie stem biomass was pyrolyzed and then treated by β-cyclodextrin/poly(L-glutamic acid) which contained plentiful functional groups. The pristine and modified biochar were characterized by FTIR, X-ray photoelectron spectroscopy, specific surface area, and zeta potential measurement. Results indicated that the β-cyclodextrin/poly(L-glutamic acid) was successfully bound to the biochar surface. Batch experiments were conducted to investigate the kinetics, isotherm, thermodynamics, and adsorption/desorption of Cr(VI). Adsorption capacities of CGA-biochar were significantly higher than that of the untreated biochar, and its maximum adsorption capacity could reach up to 197.21 mg/g at pH 2.0. Results also illustrated that sorption performance depended on initial solution pH; in addition, acidic condition was beneficial to the Cr(VI) uptake. Furthermore, the Cr(VI) uptake was significantly affected by the ion strength and cation species. This study demonstrated that CGA-biochar could be a potential adsorbent for Cr(VI) pollution control.