辽河油田石油污染土壤的2阶段生物修复

建立了污染土壤预制床处理工程,对不同类型原油污染土壤分别进行堆腐处理,历时2个阶段,共运行210d.当稀油、稠油、特稠油和高凝油污染土壤中石油烃总量(TPH)为25.8～77.2g·kg^-1时,经过53d(为第1阶段)的运行,TPH去除率38.37%～56.74%.第2年(为第2阶段)继续处理156d,TPH降解率达到66.59%～80.96%.连续运行结果表明,污染土壤中易分解的石油烃污染物大部分在第1阶段得到降解,第二阶段降解率明显降低.     

花卉废物和牛粪联合堆肥中的氮迁移

以花卉废物和牛粪为原料,进行了温度反馈的通气量控制联合堆肥中的氮迁移中试研究.采用自制的静态好氧床进行一次发酵,过程控制采用温度反馈通气量控制方法,发酵周期20d;采用周期性翻堆进行物料二次腐熟,腐熟周期40d.研究了堆肥过程中总氮、有机氮、无机氮、氨氮、硝氮等氮素形态转化随时间的变化特征及温度反馈的通气量控制对氮迁移的影响.结果表明:堆肥初期的氨化作用和反硝化作用显著,氮素总量损失累计达41.98%,其中主要是有机氮的损失,99.95%的氮损失发生在一次发酵阶段;氮素损失主要是在pH和温度较高条件下的氨气大量挥发造成的.对通风进行有效控制、提高物料C/N及添加酸性物质有望减少N损失.对于C/N较低,硝态氮含量较高的物料堆肥,NH₄⁺-N≤0.04%、NH₄/NO₃≤0.16不能作为腐熟度指标.     

Characterization of fulvic acids during olive mill waste composting (Elemental,Thermal and fluorescence analyses)

Elemental analysis, fluorescence spectroscopy and differential scanning calorimetry (DSC) were applied to the study of fulvic acids isolated from different stages during olive mill waste composting. The fulvic extracted acids are characterized by a high nitrogen content and O/C ratio values that may result from the high degree of humification and the synthesis of more condensed humic complexes. This was confirmed by fluorescence spectroscopy in the synchronous-scan mode by the decrease of shoulder intensities at intermediate wavelengths indicating the increase of polycondensation and conjugation of unsaturated structures and the greater uniformity of fluorophores. Fluorescence spectra in the emission, excitation and synchronous modes became simpler with compost maturation. This was confirmed by DSC results which proved the high degree of polycondensation of aromatic nuclei of fulvic acid molecules during olive mill waste composting.     

城市生活垃圾好氧堆肥中氨气变化及其影响

堆肥过程中氮素损失比较严重,而氨气挥发是氮损失的主要途径。利用城市生活垃圾进行好氧堆肥,研究其堆肥过程中氨气变化规律及其对堆肥性质的影响。结果表明:在堆肥期间,氨气含量先增加后减小,最后基本稳定在5 mg/kg左右;而全氮含量先降低后增加;硝态氮含量先降低后增加;铵态氮是先快速增加,后缓慢减小至稳定;pH值先下降后升高,最终稳定在中性范围内;w(C)/w(N)先增加后下降;有机质含量显著下降。     

Nitrogen-retaining property of compost in an aerobic thermophilic composting reactor for the sanitary disposal of human feces

Aerobic composting is a method for the sanitary disposal of human feces as is used in bio-toilet systems. As the products of composting can be utilized as a fertilizer, it would be beneficial if the composting conditions could be more precisely controlled for the retention of fecal nitrogen as long as possible in the compost. In this study, batch experiments were conducted using a closed aerobic thermophilic composting reactor with sawdust as the bulk matrix to simulate the condition of a bio-toilet for the sanitary disposal of human feces. Attention was paid to the characteristics of nitrogen transformation. Under the controlled conditions of temperature at 60°C, moisture content at 60%,anda continuous air supply, more than 70% fecal organic removal was obtained, while merely 17% fecal nitrogen loss was observed over a two-week composting period. The nitrogen loss was found to occur mainly in the first 24 h with the rapid depletion of inorganic nitrogen but with an almost unchanged organic nitrogen content. The fecal NH₄-N which was the main component of the inorganic nitrogen ( > 90%) decreased rapidly in the first day, decreased at a slower rate over the following days, and finally disappeared entirely. The depletion of NH₄-N was accompanied by the accumulation of NH₃ gas in the ammonia absorber connected to the reactor. A mass balance between the exhausted NH₃ gas and the fecal NH₄-N content in the first 24 hours indicated that the conversion of ammonium into gaseous ammonia was the main reason for nitrogen loss. Thermophilic composting could be considered as a way to keep a high organic nitrogen content in the compost for better utilization as a fertilizer.     

新型堆肥生物反应器人粪便堆肥功效的评价

利用以锯末为载体的Bio-Lux S15型生态卫生设备,对人粪便进行了连续性堆肥实验,考察了BOD5、粪大肠菌和蛔虫卵的灭活以及最终产品N、P和K等肥料成分的含量。实验结果表明,最初30 d,BOD5的累积去除率由27%快速增加到50%,之后的30 d维持在50%左右,随后下降至40%左右。生态卫生设备中维持50-60℃的温度是杀灭粪便病原微生物的适宜条件,可保证粪便投入后在24 h内,粪大肠菌的灭活率达到99.99%,蛔虫卵的灭活率在2 h内达100%。对反应周期内载体的N、P和K等肥料成分的分析结果表明,反应过程中3种肥分都持续积累,在反应末期,按TN、P2O5和K2O计算的3种肥分最终分别达到25.1、123.4和2.0 g/kg,基本上达到了农用肥料的国家标准,表明以锯末为载体的反应器具有良好的堆肥效果。     

Household organic waste composting using bins with different types of passive aeration

The objective of this study was to study the performances of six 200-L polyethylene bins, each with different design for passive aeration to organic wastes composting. Food scraps and dry leaves (1.6 kg) were added to each bin once a day until the bin was full. Temperatures at the middle portion were measured daily. The compost from each bin was taken once a week for 120 days for analysis of C, N, volatile solids, and a germination index once a week for 120 days. After 120 days, the compost sample from each bin was taken to determine the mass reduction, size distribution, CEC, N, P and K values. The results showed that the temperatures inside the bins were in the ranges of 24 °C-57 °C. The composts in all bins were found to be stable at around 56-91 days. The wastes decayed fastest in bins with lateral and vertical systems of natural ventilation. It took about two months to stabilize the organic wastes, with a 59-62% decrease of mass. The C/N ratio, CEC, N, P, and K values of the final composts were 14.8-16.0, 66-68 cmol/kg, and 1.26-1.50% N, 0.52-0.56% P₂O₅ and 1.66-1.92% K₂O, respectively.     

Overview of non-hazardous solid waste in the small island state of Mauritius

In Mauritius, solid waste disposal has been a cause for concern since the 1980s. Currently, there is no segregation of waste and some 1200 tonnes of solid waste are generated daily by the 1.24 million inhabitants of the island. As processes such as recycling and composting are still in their infancy stage, most of the waste generated have to be disposed of at the sole landfill. The solid waste management practices of 1980s and early 1990s are no longer compatible with the changing composition and quantity of wastes now generated. As a result, there is an urgency to review the whole waste management system and come forward with sustainable solutions.This paper presents an overview of the disposal of non-hazardous solid waste in Mauritius and provides recommendations for improving the current disposal system.     

堆肥过程中有机质和微生物群落的动态变化

利用3个容积约为50 L的平行生物反应装置研究堆肥过程中温度、湿度（水分含量）、pH值和有机质的动态变化情况。按照Van Soest方法根据有机质不同的溶解特性将其分为：溶于沸水的有机质H2O、溶于中性试剂的有机质SOLU、半纤维素（HEMI）、纤维素（CELL）和木质素（LIGN）。结果表明：反应装置内环境湿度调控在60%左右时,堆肥系统内借助生化反应,温度最高可达到约50℃。堆肥材料在反应初期呈现偏酸性（pH=6.5）,而随着反应的发生,pH逐渐变为中性或弱碱性（pH=7.4）。经过20 d的堆肥实验,有机质总量降解了约47%。在微生物作用下的各类有机质的降解率不同,按大小排序为H2O〉HEMI〉CELL〉SOLU〉LIGN,其降解率分别是85%、56%、36%、32%和27%。为了深入理解堆肥过程中有机质的降解机制,文章采用磷脂脂肪酸（PLFAs）技术对体系中的微生物群落变化进行了初步分析,发现微生物优势群落随反应温度的改变发生明显变化,在堆肥初期和堆肥中期,细菌占优势,而堆肥末期时真菌比例较高。在堆肥的过程中,革兰氏阴性菌的比例呈下降趋势,而革兰氏阳性菌的比例呈上升趋势。     

牛粪堆肥系统环境因子对抗性基因的影响

本研究利用实时定量PCR技术检测牛粪60 d好氧堆肥过程中典型四环素类抗性基因(tet Q、tet W、tet M、tet G、tet A和tet X)和大环内酯类抗性基因(erm35、erm36、erm B、erm F、erm T和erm X)的数量变化规律,系统研究了温度、含水率、挥发性有机质(VS)含量、碳氮比(C/N)、pH值、氧化还原电位(ORP)等堆肥系统环境因子和细菌数量(TCB)对这两类典型抗生素抗性基因的影响.结果表明,堆肥升温阶段牛粪中tet Q、tet W、tet G和tet X数量分别增加1. 7、0. 3、84. 8和4. 5倍,而tet M丰度降低了83. 1%;堆肥腐熟阶段牛粪中tet G和tet X数量分别增加23. 8和11. 5倍,而tet W、tet Q和tet M数量均降低90%.整个牛粪堆肥过程中erm35、erm36、erm B、erm F、erm T和erm X丰度分别增加2. 1、430. 4、0. 6、11. 5、2. 1和49. 1倍. RDA分析表明,牛粪堆肥过程中对四环素与大环内酯类抗性基因数量影响较大的3个环境因子分别为:ORP(54. 8%)、温度(34%)和VS(11. 3%),其中ORP与erm X和erm B、温度与tet Q和erm F以及VS与tet W数量均呈明显地正相关.