城市污泥为掺料烧结砖的生产性试验研究

进行了城市污泥为部分原料生产烧结砖的生产性试验。结果表明：污泥掺量在6%和5%之内的页岩及粘土烧结普通砖，强度等级分别达到MU10和MU15（GB5101-2003）以上，均可作为承重砖体使用。污泥掺量在5%之内的页岩烧结空心砌块，强度等级为MU3.5（GB13545-2003），可作为填充墙（或隔离墙）使用。研究结果还表明：4.45%泥掺量页岩烧结普通砖热导率为0.295 W/(m·K),较普通页岩砖0.312 W/(m·K)明显降低；4.45%干污泥掺量页岩空心砌块墙体传热系数为1.33 W/(m²·K)，满足《夏热冬冷地区居住建筑节能设计标准》（JGJ 134-2001） 1.5 W/(m²·K)的要求，节能效率提高11.3%，墙体隔热保温性能得到显著改善。     

不同类型透水砖对雨水径流水量的控制效果

透水铺装是目前海绵城市建设中应用较广泛的技术措施之一,对雨水径流的促渗减排发挥着重要作用。选择2种不同类型透水砖为研究对象,采用人工模拟降雨实验方法,研究了降雨重现期分别为1、3、5、10 a条件下,2种不同类型透水砖对雨水径流总量控制、峰值削减和峰值延迟等方面的控制效果。结果表明:在降雨重现期小于10 a的条件下,构造透水砖和普通透水砖的场次降雨总量控制率平均值均超过95%;峰值流量均随着重现期的增加而增大,构造透水砖的峰值削减效果优于普通透水砖,平均峰值削减率提高了8.6%;构造透水砖和普通透水砖的出流延迟时间平均值分别为11.3 min和13.8 min,平均峰值延迟时间分别为6.3 min和16.3 min。构造透水砖对径流总量、峰值流量的控制效果要优于普通透水砖,因此,在透水铺装应用中,应结合项目设计目标和当地的水文地质条件,宜优先考虑采用构造透水砖铺装方式。     

污泥渗水砖的制备研究

结合压制成型和传统的烧结砖工艺，实验以城市生活污泥、黄河淤泥、煤矸石及砂为原料，制备渗水铺地砖。通过正交试验得到最优工艺参数为w_{(黄河淤泥)}∶ww_(煤矸石)∶w_(污泥)∶w_(砂)＝33％∶22％∶15％∶30％、成型压力为20 MPa、烧结温度为1 100℃、保温时间为1.5 h，骨料砂的粒径为1～2 mm。制备的成品抗压强度为21.8 MPa，渗水系数为1.03×10^－2 cm/s。并对成型压力及烧结温度对渗水砖抗压强度及渗水系数的影响进行了讨论。     

干化污泥制备节能烧结墙体材料

以干化污泥作为替代燃料和造孔剂加入到以页岩为主体的原料体系中,制备出具有节能效果的多孔污泥页岩烧结墙体材料,这是提高污泥利用效率和满足村镇建筑节能建材制备的有效手段,探究了城市污泥掺量、烧结温度和烧结保温时间对烧结墙体材料试样的物理性能、力学性能的影响规律。结果表明,在采用污泥和瘠性页岩为主要原料时不能满足多孔节能烧结墙体材料挤出成型要求,而应采用压制成型工艺,当污泥掺量为15%时,烧结温度为1 050℃,保温时间为6 h,可以制备出性能指标优异并满足工程实用的烧结墙体材料,且污泥中的重金属可有效固溶于材料内部,气体排放也可满足国家标准中的相关指标要求,研究结果对干化污泥的利用具有较好的指导意义。     

化工污泥基轻质填料的制备及其应用

将化工污泥焚烧灰渣掺入粘土、干燥化工污泥为原料,添加自制无机重金属稳定剂S01,经烘干、预热、焙烧等工艺过程,制备了粒径为10~20 mm的水处理填料。通过单因素实验考察了干污泥添加量、污泥焚烧灰渣添加量、S01添加量、预热时间、烧结温度等工艺条件对填料性能(堆积密度、吸水率)的影响,确定了填料的最佳制备条件:干污泥添加量20%,焚烧灰渣添加量40%,S01添加量5%,预热时间30 min,烧结温度1 150℃。此时,填料的堆积密度为569.11 kg/m3,吸水率为9.84%,重金属浸出浓度远远低于《危险废物鉴别标准浸出毒性鉴别(GB5085.3-2007)》的浓度限值。采用扫描电镜观察了填料表面和内部孔隙特征,发现最佳制备条件下制得的填料表面粗糙多孔,内部具有发达的孔道结构。开展了填料的生物挂膜研究,结果表明,在挂膜启动13 d后,化工污泥基填料滤池的COD和氨氮去除率均趋于稳定,分别达到95.6%和71.8%,该处理效果略优于市售填料。验证了化工污泥基填料应用于生物滤池的可行性。     

以城市污泥为掺料制备烧结砖

以城市污泥为部分原料制备烧结砖,对不同烧成温度下不同污泥掺量的烧结砖的物理、力学性能进行了详细分析。结果表明,污泥可用于制备烧结砖,当污泥掺量≤12%,烧成温度为1 100℃时,烧结砖物理力学性能均符合烧结砖标准要求。此外,实验以污泥掺量为12%的烧结砖,烧成温度为1 100℃为例,进行了重金属毒性浸出实验,以考察烧制污泥砖对重金属的固化作用,进而评定污泥制砖的安全性。结果表明,经过高温焙烧,大多数重金属浸出毒性都显著降低,且符合规范要求,不会对环境造成危害。其中,重金属固化效果最好的为Zn,最差的为Cr。     

利用拜耳法赤泥和氟化钙污泥制备烧结砖块

拜耳法赤泥是用氢氧化钠溶解铝土矿生产氧化铝过程中产生的固体废弃物。针对拜耳法赤泥的强碱性、重金属含量高等特点,提出了一种利用酸性氟化钙污泥进行共同烧制砖块的方法。以砖块的氟离子浸出量、铬离子浸出量、抗压强度、砖块密度及烧失量5个变量为评价指标,利用主成分分析法对五个指标进行综合评分,并研究了以氟化钙污泥与赤泥比,黏土添加量、铝灰添加量、黏结剂添加量、烧结温度为自变量对综合评分的影响。利用响应面法(RSM)对实验数据进行分析,得出最佳实验条件依次为氟化钙污泥与赤泥比=61.1%,黏土添加量=21.4%,铝灰添加量=15%,黏结剂添加量=2.5%,烧结温度=1 000℃。此条件下所得砖块对应的氟离子浸出量为0.33 mg·L~(-1),铬离子浸出0.034 mg·L~(-1),抗压强度5.73 MPa,烧失量9%,砖块密度1.07 g·cm~(-3)。可用做非承重砖。     

利用烧结脱硫灰制备胶凝材料的研究

研究了烧结烟气半干法脱硫灰复掺矿渣、钢渣，辅之外加剂，制备胶凝材料的可行性。结果表明，采用改性脱硫灰（GXTLH）、钢渣、矿渣及水泥熟料再混磨制备的复合胶凝材料，具有良好的安定性等水化性能和力学性能；当GXTLH 掺入量为20%、CFII 1.5%、减水剂0.5%及水泥熟料23%时，矿渣掺量在12%～44%、钢渣掺量11%～44%之间制备的胶凝材料初凝时间、终凝时间、力学性能满足GB13592-92《钢渣矿渣水泥标准》；矿渣与钢渣比、水泥熟料及外加剂等掺量一定，GXTLH掺量超过30%时，GXTLH胶凝材料的抗压抗折强度均有所下降。     

城市生活污泥烧结制陶粒的两种工艺比较研究

通过试验比较了"湿法造粒-烧结"和"干化-烧结"2种利用城市生活污泥烧结制陶粒的工艺路线.分析了工艺路线、原料配比和烧结温度对污泥陶粒的产品强度、吸水率和密度等性能指标的影响,同时指出了沸石粉和粘土作为助熔剂的不同作用机理和作用温度.实验结果表明,污泥"干化-烧结"制陶粒更有优势.烧结陶粒不会造成二次污染.综合考虑产品性能与经济性,适宜的物料配比为干污泥50%、粉煤灰30%～40%、粘土10%～20%.     

污泥与底泥烧结陶粒骨料的中试研究

建立了中试研究生产线,工艺流程包括干燥、粉磨、混合上料、成型、烧结和烟气处理等,在中试生产线上,对污泥(包括工业污泥(ISS)和生活污泥(DSS))与底泥烧结制备陶粒骨料的物料配比、烧结温度、添加剂等相关技术参数进行了系统研究。研究发现,ISS中CaO和磷的化合物含量较高,导致骨料的膨胀性能不佳,添加一定量的生活污水污泥(DSS)可改善骨料的膨胀性能。中试研究确定600～800级的陶粒骨料烧结的适宜工艺条件为:配比SS∶DSS∶RS=1∶4∶5～1∶5∶4或DSS∶RS=3∶7～5∶5,烧结温度1 140℃,烧结时间28 min环境安全性研究表明,在陶粒烧结过程中大部分重金属在烧结过程中被固定在陶粒中,重金属浸出率非常低,在使用过程中不会对环境产生危害。     

Chloroaromatic pollutants in mussels incubated in two finnish watercourses polluted by industry

Concentrations of different chlorinated compounds were measured in mussels incubated in two polluted watercourses, a river (the River Kymijoki) and a lake (Lake Vanaja) for four weeks in summer 1995. The sum concentrations of polychlorinated phenols (PCP) and biphenyls (PCB) were both about 1 μg/g lipid weight (lw) in Lake Vanaja mussels, while in the River Kymijoki mussels PCPs were non-detectable and PCBs were measured 120 ng/g lIw. The concentrations of toxic polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners ranged between <17 and 370 pg/g Iw in Lake Vanaja mussels and between <38 and 11,000 pg/g lw in the River Kymijoki mussels. Polychlorinated diphenyl ethers (PCDE) were detected in the mussels incubated in the River Kymijoki (0.4–1.1 ng/g Iw), but not in those incubated in Lake Vanaja. Polychlorinated phenoxyanisoles (PCPA) were measured 33 ng/g lw and polychlorinated phenoxyphenols (PCPP) 300 ng/g lw in the mussels incubated in the River Kymijoki. PCPAs were also detected in reference samples, which were sediment and pike from the River Kymijoki and Baltic salmon, seal and white-tailed sea eagle.     

Book review

The Pesticide Manual ‐ A World Compendium, 8th Edition, C.R. Worthing, Editor and S.B. Walker, Assistant Editor, British Crop Protection Council, BCPC Publications Sales, Bear Farm, Binfield, Bracknell, Berkshire RG12 5QE, England. 1987, 1100 pp., UK £50; Overseas £56. ISBN 0–948404–01–9.     

Patterns of volatile metabolites and nonvolatile trichothecenes produced by isolates of <Emphasis Type="Italic">Stachybotrys,Fusarium, Trichoderma,Trichothecium</Emphasis> and <Emphasis Type="Italic">Memnoniella</Emphasis>

We reported previously that trichodiene, a volatile trichothecene derivative, was produced by a Stachybotrys isolate, also known to produce highly cytotoxic, non-volatile, macrocyclic trichothecenes (satrotoxins). We investigated the relationship between the production of trichodiene and various non-volatile trichothecenes for several molds. Volatile metabolites were concentrated by adsorption on Tenax TA and analyzed by GC/MS, while non-volatile metabolites were separated by HPLC, derivatized and analyzed by GC/MS. Stachybotrys chartarum isolates producing macrocyclic trichothecenes secreted significantly larger amounts of trichodiene and other sesquiterpenes than isolates which only produced simple trichothecenes. The amounts of secreted trichodiene were relatively small in all cases. With the exception of Memnoniella, which excreted small amounts of sesquiterpenes, the other isolates produced varying amounts of sesquiterpenes, including trichodiene, as well as simple tricothecenes, no detectable trichodiene, but large amounts of griseofulvin derivatives. In Stachybotrys there is apparently a correlation between trichodiene and macrocyclic trichothecene production. In the remaining isolates, there was no simple relationship between trichodiene and non-volatile trichothecene synthesis. Trichodiene is produced in larger amounts by Stachybotrys isolates, which also produce satratoxins, but it will be difficult to utilize this metabolite to detect toxic isolates in buildings due to the relatively small amounts excreted.     

The chemical stability of formulations of some hydrolyzable insecticides in aqueous mixtures with hydrolysis catalysts

Abstract

The active ingredients in commercial formulations of malathion, oxamyl, carbaryl, diazinon, and chlorpyrifos diluted to “spray tank”; concentrations with buffered distilled or natural water of pH 4–9 were stable for at least 24 hr. Formulations of trichlorfon were not stable at pH 7 or above but disappearance rates were slower than for the pure chemical in homogeneous solution. Cupric ion was observed to be an effective catalyst for the hydrolysis of a variety of pure organophosphorus insecticides but did not catalyze hydrolysis of the active ingredients of the formulations examined. Increasing the dilution of the formulation increased the susceptibility of malathion, oxamyl, and carbaryl to hydrolysis.     

Organochlorine compounds in a three-step terrestrial food chain

The concentrations of 15 organochlorine chemicals (PCBs and pesticides) were studied in a Central European oak wood food chain system: Great tit (Parus major), caterpillars (Tortrix viridana, Operophtera brumata, Erannis defoliaria), and oak-leaves (Quercus robur). Juvenile tits receive organochlorines from the mother via egg transfer and, eventually to a greater extent, from the caterpillar food source during nestling period. The concentrations of PCB 153 (2,2′,4,4′,5,5′-hexachlorobiphenyl, the most abundant in this study) was found in leaf material at ca. 1 ng/g, in caterpillars 10 ng/g, and in bird eggs 170 ng/g on an average and on a dry mass basis.     

Radionuclides and trace elements in fish collected upstream and downstream of Los Alamos national laboratory and the doses to humans from the consumption of muscle and bone

Abstract

The purpose of this study was to determine radionuclide and trace element concentrations in bottom‐feeding fish (catfish, carp, and suckers) collected from the confluences of some of the major canyons that cross Los Alamos National Laboratory (LANL) lands with the Rio Grande (RG) and the potential radiological doses from the ingestion of these fish. Samples of muscle and bone (and viscera in some cases) were analyzed for ³H, ⁹⁰Sr, ¹³⁷Cs, ^totU, ²³⁸Pu, ^239,240Pu, and ²⁴¹Am and Ag, As, Ba, Be, Cr, Cd, Cu, Hg, Ni, Pb, Sb, Se, and Tl. Most radionuclides, with the exception of ⁹⁰Sr, in the muscle plus bone portions of fish collected from LANL canyons/RG were not significantly (p<0.05) higher from fish collected upstream (San Ildefonso/background) of LANL. Strontium‐90 in fish muscle plus bone tissue significantly (p<0.05) increases in concentration starting from Los Alamos Canyon, the most upstream confluence (fish contained 3.4E‐02 pCi g^‐1 [126E‐02 Bq kg^‐1]), to Frijoles Canyon, the most downstream confluence (fish contained 14E‐02 pCi g^‐1 [518E‐02 Bq kg^‐1]). The differences in ⁹⁰Sr concentrations in fish collected downstream and upstream (background) of LANL, however, were very small. Based on the average concentrations (±2SD) of radionuclides in fish tissue from the four LANL confluences, the committed effective dose equivalent from the ingestion of 46 lb (21 kg) (maximum ingestion rate per person per year) of fish muscle plus bone, after the subtraction of background, was 0.1 ± 0.1 mrem y^‐1 (1.0 ± 1.0 μSv y^‐1), and was far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem y^‐1 (1000 μSv y^‐1). Of the trace elements that were found above the limits of detection (Ba, Cu, and Hg) in fish muscle collected from the confluences of canyons that cross LANL and the RG, none were in significantly higher (p<0.05) concentrations than in muscle of fish collected from background locations.     

Radionuclides in pinon pine (Pinus edulis) nuts from los alamos national laboratory lands and the dose from consumption

Abstract

One of the dominant tree species growing within and around the eastern portion of Los Alamos National Laboratory (LANL), Los Alamos, NM, lands is the pinon pine (Pinus edulis). Pinon pine is used for firewood, fence posts, and building materials and is a source of nuts for food—the seeds are consumed by a wide variety of animals and are also gathered by people in the area and eaten raw or roasted. This study investigated the (1) concentration of ³H, ¹³⁷Cs, ⁹⁰Sr, ^totU, ²³⁸Pu, ^{239, 240}Pu, and²⁴¹ Am in soils (0‐ to 12‐in. [31 cm] depth underneath the tree), pinon pine shoots (PPS), and pinon pine nuts (PPN) collected from LANL lands and regional background (BG) locations, (2) committed effective dose equivalent (CEDE) from the ingestion of nuts, and (3) soil to PPS to PPN concentration ratios (CRs). Most radionuclides, with the exception of ³H in soils, were not significantly higher (p < 0.10) in soils, PPS, and PPN collected from LANL as compared to BG locations, and concentrations of most radionuclides in PPN from LANL have decreased over time. The maximum net CEDE (the CEDE plus two sigma minus BG) at the most conservative ingestion rate (10 lb [4.5 kg]) was 0.0018 mrem (0.018 μSv); this is far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem (1000 μSv). Soil‐to‐nut CRs for most radionuclides were within the range of default values in the literature for common fruits and vegetables.     

Degradation and sorption of imidacloprid in dissimilar surface and subsurface soils

Degradation and sorption/desorption are important processes affecting the leaching of pesticides through soil. This research characterized the degradation and sorption of imidacloprid (1-[(6-chloro-3-pyridinyl)-methyl]-N-nitro-2-imidazolidinimine) in Drummer (silty clay loam) and Exeter (sandy loam) surface soils and their corresponding subsurface soils using sequential extraction methods over 400 days. By the end of the incubation, approximately 55% of imidacloprid applied at a rate of 1.0 mg kg^?1 degraded in the Exeter sandy loam surface and subsurface soils, compared to 40% of applied imidacloprid within 300 days in Drummer surface and subsurface soils. At the 0.1 mg kg^?1 application rate, dissipation was slower for all four soils. Water-extractable imidacloprid in Exeter surface soil decreased from 98% of applied at day 1 to > 70% of the imidacloprid remaining after 400 d, as compared to 55% in the Drummer surface soil at day 1 and 12% at day 400. These data suggest that imidacloprid was bioavailable to degrading soil microorganisms and sorption/desorption was not the limiting factor for biodegradation. In subsurface soils > 40% of ¹⁴C-benzoic acid was mineralized over 21 days, demonstrating an active microbial community. In contrast, cumulative ¹⁴CO₂ was less than 1.5% of applied ¹⁴C-imidacloprid in all soils over 400 d. Qualitative differences in the microbial communities appear to limit the degradation of imidacloprid in the subsurface soils.     

Biochemical interaction of six op delayed neurotoxicants with several neurotargets

Abstract

Five organophosphorous insecticides: Leptophos, EPN, Cyano‐fenphos, trichloronate and salithion proved to cause irreversible ataxia not only to chicken but also to mice and sheep. TOCP was included as a reference. Cyanofenphos blocked the catecholamine B‐receptor binding activity with ³H‐norepinephrine at a level similar to that of the specific inhibitor propranolol in the mouse heart preparation. In the lamb heart preparation, the B‐receptor was more sensitive to Leptophos, salithion and TOCP than to propranolol. The six compounds and their oxons were screened for their in‐vitro inhibition to monamine oxidase (MAO), acetyl cholinesterase (AChE) and neurotoxic esterase (NTE) in the brain of either mouse, lamb or chicken. It is believed that their AChE inhibition stands for their acute toxicity, while NTE inhibition is responsible for their paralytic ataxia.