微量金属对AF处理模拟焦化废水运行的影响

本文研究了投加微量金属元素对小试规模上流式厌氧滤波池处理模拟焦化废水的影响。研究结果表明，投加微量金属元素Fe,Co,Ni可以加速厌氧反应器的启动并缩短厌氧反应器对难降解物质的驯化期。不同水力停留时间（HRT）下的运行情况对比表明，投加微量金属元素Fe,Co,Ni可以提高厌氧反应器的抗冲击负荷能力。     

金属离子对剩余污泥和生活垃圾联合厌氧消化的影响

以城市有机生活垃圾和污水处理厂剩余污泥作为发酵原料,在相同条件下,研究不同浓度的Fe2+,Co2+,Ni2+组合对厌氧消化过程和消化效率的影响。结果表明,添加金属离子能提高垃圾的消化效率,当Fe2+,Co2+,Ni2+的浓度分别为3 mg·L-1,1.5 mg·L-1,1.5 mg·L-1时厌氧消化效果最好,COD降解率为71.14%,TS去除率为48.83%,VS去除率为69.34%,与对照相比分别提高了13.79%,17.09%,15.54%。     

ICP-MS法测定金银花花蕾中27种金属元素含量

采用电感耦合等离子体质谱(ICP-MS)法测定了湖北神农架产金银花花蕾中27种金属元素的含量。其中13种金属元素V、Cr、Mn、Fe、Cu、Zn、As、Se、Mo、Ag、Cd、Tl、Pb等采用普通模式检测,14种金属元素Li、Be、B、Mg、Al、Co、Ni、Ga、Rb、Sr、Te、Ba、Bi、U等采用碰撞/反应池技术(CCT)模式测定,以消除样品溶液中潜在的干扰。实验条件下,Co、Ni、Cr、Zn、Se、Mo、Ag、Pb等8种金属元素未检出。方法检出限Fe为9.789ng/mL、Cr为2.691ng/mL,Zn为1.803ng/mL,B为2.076ng/mL,Mg为1.977ng/mL,Al为3.024ng/mL,Ni为1.824ng/mL,其它元素为0.003～0.921ng/mL,精密度的RSD为0.146%～7.627%,加标回收介于90.0%～110.0%之间。     

不同营养元素组合对高浓度制药废水产沼气的影响研究

添加产甲烷菌所需的主要营养物质N, P, S及微量刺激金属元素Fe, Co, Ni,可以提高营养缺乏型制药废水的产气效率.通过不同添加物组合与对照比较,考察厌氧生物处理过程中的产气量与COD去除情况,试验结果表明,处理2获得本实验最佳处理效果,其废水中N, P, FeSO4·7H2O, NiCl2·6H2O, CoCl2·6H2O的添加浓度分别为100 mg·L-1, 200 mg·L-1, 300 mg·L-1, 1.0 mg·L-1, 1.0 mg·L-1,废水的产气量提高了18%,COD去除率提高了1.29%.     

微量元素对玉米秸秆厌氧发酵产沼气及辅酶F_(420)的影响

以玉米秸秆为厌氧发酵基质,以微量元素Fe、Co、Ni混合液为添加液,研究中温条件下微量元素的添加对玉米秸秆厌氧发酵产沼气及辅酶F420活性的影响,探讨添加频次与产气效果的关系。结果表明:添加微量元素试验组的累积产气量和产气率稳定性优于未添加试验组;微量元素的添加频次不同,其产气效果也不同;当微量元素混合液中Fe、Co、Ni的浓度为1.0、0.1、0.2mg/L时,每天添加微量元素的试验组产沼气效果最佳,比未添加组累积产气量提高23%,TS、VS降解率分别提高16.1%和22.3%,辅酶F420含量高峰值显著提高。本研究为提高玉米秸秆厌氧发酵的产气效果提供了依据。     

化学促进剂对寒区猪粪沼气发酵的影响及其工程示范

为研究寒区猪粪厌氧发酵产沼气时化学促进剂对反应体系发酵产气的影响,文章进行了化学促进剂的筛选试验以及最佳组合的配比试验,最后进行现场工程投加示范。实验结果显示,除Mo外,添加微量元素和生长因子都改善了产气量,其中,以酵母粉与Fe,Co,Ni的组合最佳;在最佳组合的四因素中,对累计产气量影响程度依次为:酵母粉﹥Co﹥Fe﹥Ni;最优组合为Fe Cl2·4H2O∶Co Cl2·6H2O∶Ni Cl2·6H2O∶酵母粉=3∶1∶1∶1;工程现场投加0.01%化学促进剂后,在10天的沼气发酵观察中,容积产气率基本都维持在0.3 m3·m-3d-1以上,最高达0.37m3·m-3d-1。通过以上结果可知,添加化学促进剂(以酵母粉与Fe,Co,Ni的组合最佳),可以提高低温环境下厌氧发酵的沼气产量和产率,并具有经济可行性和实际效益。     

微量金属元素添加频率对牛粪厌氧发酵细菌种类的影响

在以牛粪为原料的厌氧发酵液里,分别以1天、3天、5天、7天的间隔时间向反应器中添加微量金属元素,研究微量金属元素对牛粪厌氧发酵特性及细菌种类的影响。结果表明,每7天添加1次的效果最佳,产气率、总产气量以及COD去除率最高,生物相里有杆菌和球菌,但是球菌占优势;每天添加1次的挥发性有机酸(VFA)和产气量都是最低的,分析认为是微量金属元素的添加对细菌造成了抑制。     

厌氧消化过程中甲烷菌的无机营养需求

厌氧消化过程缺乏无机营养元素所产生的不利影响比对好氧处理过程要大。厌氧发酵的甲烷发酵阶段对无机营养的缺乏更为敏感。一般说缺乏无机营养元素主要指微量金属元素。本文综述迄今有关甲烷菌无机营养需求方面的重要研究成果。特别强调发现Ｎｉ是甲烷菌必要的营养元素。研究结果表明，甲烷菌对Ｓ和Ｆｅ的需要量也比过去所认为的要多。补充甲烷菌所需的必要无机营养元素，主要是微量金属元素，是提高厌氧消化效率的重要途径。     

螺旋对称流厌氧反应器床层颗粒污泥金属元素时空变化

金属元素对厌氧颗粒污泥(AGS)的颗粒化、致密性和沉降性能等具有重要作用。文章以UASB反应器为参比,研究了螺旋对称流厌氧反应器(SSSAB)床层AGS中金属元素的时空变化规律。结果表明:SSSAB床层AGS中金属元素总量在时间上先升后稳,由接种污泥的18.81 mg·g-1SS,逐步提升并稳定在40 mg·g-1SS左右,稳定运行后的SSSAB反应器COD平均去除率达86.74%;SSSAB床层AGS中Ca和Cr等金属元素在空间上呈现梯度分布,它们与反应器高度呈正相关;金属元素总量在空间上也呈现梯度分布,它与反应器高度呈负相关,而UASB反应器则无明显的梯度分布规律。     

地下水三氯甲烷污染的微生物治理实验研究

在厌氧环境中,以三氯甲烷为靶污染物,分6种条件加入不同共代谢基质对厌氧生物污泥分别进行驯化培养。将得到的可降解三氯甲烷的微生物菌群富集培养,分别投入模拟净化装置进行处理实验。实验结果表明,在厌氧条件下,三氯甲烷能够被微生物降解,加入共代谢基质后可提高降解效率。不同基质环境中降解效率不同,以葡萄糖和甲醇为共代谢基质驯化出的微生物菌群对污染物去除率可达到75%。     

Contamination of shallow groundwater system and soil-plant transfer of trace metals under amended irrigated fields

This study focuses on experimental pilot assessment of contamination of shallow groundwater systems and soil-plant transfer of trace metals under amended irrigated fields. The study approach involved a pilot experimental (greenhouse) set-up of organo-mineral amended test plots/troughs (40 cm × 47 cm × 46 cm) planted with two common vegetable crops (Amaranthus hybridus and Abelmoschus esculentus) and irrigated with wastewater. In addition to the geochemical analyses of the primary un-amended and amended soils before planting as well as residual soils after harvesting, measurements of the physico-chemical parameters and chemical analyses of trace metals concentrations in irrigation leachates and harvested vegetable tissues were also undertaken following appropriate standard sample preparation and analytical methods.The results of the geochemical analyses carried out on irrigation leachate samples collected during the sprouting stage revealed that most of the analyzed trace metals in the collected leachates exhibited 2-10 folds depletion (except for Cu and Co with enrichment of about 1.5-3 folds) compared to the initial wastewater used for irrigation. A situation attributed to uptake/bioaccumulation of these metals and selective enrichment in the residual soils as well as to leaching by infiltrating irrigation water. Nonetheless, the observed higher trace elements concentrations in the second sets of leachates collected during harvesting stage compared to the first sets of leachates collected during the sprouting/vegetative stage is an indication of higher plant uptake during sprouting/vegetative stage or initial sorption/complexation of biosolids amendment before later vertical re-mobilization by infiltrating irrigation water.Although, virtually all of the analyzed metals exhibited elevated concentrations (2-173 ppm) in both A. hybridus and A. esculentus, a closer evaluation revealed 1.2-8.2 folds enrichment of Cr, Co, Ni, Cd, Cu, and Pb in A. esculentus compared to that of A. hybridus, an indication of the fact that phyto-accumulation of trace metal is plant-specific and dependent on physiological set-up. The overall evaluation had clearly demonstrated the potential danger of bioaccumulation of toxic trace metals under biosolid amended soils as well as impacts of irrigation-induced leaching on the shallow groundwater quality, while the need to evolve a sustainable agricultural practices is also highlighted.

Capsule

Organo-mineral amendment can lead to trace metal bioaccumulation (in plants) and irrigation-induced leaching to shallow groundwater system.     

Emission of Nitrous Oxide and other Trace Gases during Composting of Grass and Green Waste

The emission of trace gases during composting of green waste from land maintenance (fresh cuttings of mixed herbage from fallow land) were studied. Concentrations of nitrous oxide and other trace gases were measured in experimental compost heaps by means of an infrared gas analyser and a high-resolution FT-IR spectrometer. It was verified that the maintenance of aerobic conditions is essential to keep emissions of methane and nitrous oxide at a low rate. Estimates made using a simple air transport model, indicated that the emission of nitrous oxide during composting of green waste from land maintenance was about 0·5% of the total nitrogen content of the initial material. Carbon monoxide was also detected in the compost air and its emission during biodegradation corresponded to about 0·04% of the initial carbon content of green waste.For a detailed evaluation of the findings during field experiments, laboratory apparatus for measuring the composition of compost air was developed. The measurements were performed at a temperature of 35°C and at different ventilation rates. Moistened plant material (dry cuttings of mixed herbage from fallow land) amended with lime saltpetre was used as compost substrate. At a ventilation rate of 100 cm³/min of air per kg of substrate, the maximum emission rate of nitrous oxide was 2·2 mg/h per kg of substrate. The maximum emission rate increased to 13·3 mg/h kg, when the ventilation rate was lowered to 20 cm³/min kg. The emission rate of carbon monoxide was about 40 μg/h per kg of substrate at the low ventilation rate and rose above 200μg/h kg at the higher ventilation rate.     

超声波提取—电感耦合等离子体发射光谱(ICP-AES)法测定婴儿米粉中的常量和微量元素

采用超声波提取—电感耦合等离子体发射光谱(ICP-AES)法提取并测定婴儿米粉中的常量和微量元素。优化超声波提取条件和ICP-AES仪器条件;测得相对标准偏差为0.71%～1.35%,加标回收率为96.1%～103.5%;通过分析国家标准物质GBW10010(大米)和GBW10012(玉米)来验证方法的准确度和精密度,结果得出测定值与标准值吻合。表明此法具有操作简便、检出限低、线性范围宽、精密度高、准确度好等优点,能同时满足微量元素和常量元素的检测要求。     

水稻田中占优势的产甲烷菌

本试验采用改良的Ｈｕｎｇａｔｅ厌氧操作技术与ＭＰＮ法，测定了二种水稻田中产甲烷菌数量，同时分离纯化了占优势的液泡甲烷八叠球菌和嗜树木甲烷短杆菌。     

水炭运筹下稻田痕量温室气体排放与水氮利用关系研究

为揭示寒地黑土稻田痕量温室气体的排放规律,以及稻田痕量温室气体排放与水分利用效率（WUE）及氮肥吸收利用率（NUE）间的关系,设置干湿交替灌溉和传统淹水灌溉2种水分管理模式,以及4个生物质炭施用量水平(0、2.5、12.5、25t/hm2),以传统淹水灌溉作为对比,应用15N示踪技术,研究水炭运筹下寒地黑土稻田甲烷和氧化亚氮排放的季节变化规律,明确稻作水氮利用与甲烷和氧化亚氮排放的关系,并计算温室气体的全球增温潜势（GWP）和排放强度（GHGI）。结果表明：生物质炭施用量相同时,传统淹水灌溉模式的甲烷排放通量显著高于干湿交替灌溉模式(P<0.05),而氧化亚氮排放通量均低于干湿交替灌溉模式。干湿交替灌溉模式的甲烷总排放量显著低于传统淹水灌溉模式(P<0.05),而氧化亚氮总排放量高于传统淹水灌溉模式,施加生物质炭对稻田甲烷、氧化亚氮减排效果显著;干湿交替灌溉模式下稻田痕量温室气体的GWP、GHGI显著低于传统淹水灌溉模式(P<0.05),施加生物质炭可以降低稻田痕量温室气体的GWP、GHGI。干湿交替灌溉模式的WUE显著高于传统淹水灌溉模式（P<0.05）,适量施入生物质炭可以增加WUE和氮肥整体、基肥、蘖肥、穗肥的NUE。两种灌溉模式稻田痕量温室气体的GWP和GHGI与WUE均呈显著负相关(P<0.05);两种灌溉模式稻田痕量温室气体的GWP、GHGI与氮肥整体、基肥、蘖肥、穗肥的NUE均呈显著或极显著负相关。     

蔬菜育苗基质块成型机设计与试验

基质块育苗移栽具有护根护苗、缓苗期短、成活率高等优点,相比穴盘钵苗,基质块苗市场保有量仍相对较少,主要受限于基质块成型加工设备配套不足,因此本文设计了一种蔬菜育苗基质块成型机,实现自动铺土、压块、投块、输送等功能为一体,通过对整机结构和传动系统、钵盘机构、压块及投块机构等关键部件进行设计,以蚯蚓粪—土壤为原料对影响基质块成型的3个因素进行正交试验,得出优选参数组合为蚯蚓粪—土壤混合配比1∶3、压缩比0.65、含水率10%,此时尺寸稳定性为98.96%,抗压力为246.86 N,散坨率为4.15%,可极大地满足基质块育苗移栽的要求,从而为基质块成型加工的研发提供理论参考。     

精对苯二甲酸生产废水厌氧处理微生物特性的研究

本文对进水经预处理及未经预处理的上流式厌氧污泥床反应器(UASB)处理精对苯二甲酸(PTA)废水过程中的主要微生物类群(产甲烷菌群,脱氮菌及脱硫菌)的消长规律,污泥特性及其优势产甲烷菌演变及与工艺的关系进行了研究。对对苯二甲酸(TA)厌氧降解菌进行了初探.     

痕灌带地埋下水力特性

为了获得痕灌带在田间应用的设计参数及其水力性能,通过室内与室外试验相结合的方法,针对流量规格为900 mL/h的痕灌带在自由出流时的制造偏差系数、流量与压力关系及其地埋后的水力特性以及痕灌毛管的地埋极限铺设距离进行了计算与评估.试验结果表明,试验痕灌带制造偏差系数为0.04,制造精度较高,且痕量灌水器压力-流量关系符合微灌灌水器幂函数关系式;痕量灌水器在地埋条件下,流量对压力变化的敏感性要高于自由出流.痕灌带(900 mL/h)在地埋后其流量减小幅度不明显,与室内自由出流相比,在额定工作压力条件下(10 m),地埋后痕量灌水器平均流量减少3%~8%;此外,在满足系统流量偏差系数(q_v)不大于20%条件下,并结合田间土壤含水率空间变异性的研究验证,试验痕灌带(900 mL/h)在平坡铺设、砂壤土中的地埋铺设极限距离为150 m左右.