三个污水处理厂污泥好氧堆肥对比试验

以三个污水处理厂的脱水污泥为研究对象,采用秸杆作为调理剂,考察污泥性质对堆肥过程的影响。结果表明,东区水质净化厂、南桥污水处理厂及奉贤区西部污水处理厂好氧发酵过程最佳污泥与秸杆干物料体积比(V泥:V调)分别为1∶0.8、1∶0.65和1∶0.8。初始污泥有机质、含氮量越丰富,高温期持续时间越长,减容率、减重率越高;初始污泥种子发芽率高时,发酵后趋势将持续,种子发芽率仍会很高。     

Degradation of yew, ragwort and rhododendron toxins during composting

Recent concerns have been raised that plants such as ragwort (Senecio jacobaea), yew (Taxus baccata) and rhododendron (Rhododendron ponticum) that are toxic to livestock may be included in compost windrows but may not be fully detoxified by the composting process. This study investigates the decomposition during composting of toxic pyrrolizidine alkaloids present in ragwort, taxines (A and B) present in yew, and grayanotoxins (GTX I, II, and III) present in rhododendron during composting. Plant samples were contained within microporous bags either towards the edge or within the centre of a pilot-scale compost heap. They were destructively harvested at regular intervals over 1200 °C cumulative temperature (about three months). Samples were analysed for levels of toxins by liquid chromatography time of flight mass spectrometry (LC-TOF-MS). Pyrrolizidine alkaloids and taxines were shown to degrade completely during the composting process. While GTX I showed significant reductions, concentrations of GTX III remained unchanged after 1200 °C cumulative temperature. However, estimates of exposure to grazing livestock coming into contact with source-segregated green waste compost containing up to 7% rhododendron suggest that GTX III poses no appreciable risk.     

Characterization of Methane Emissions from Rice Fields in Asia. III. Mitigation Options and Future Research Needs

Methane (CH₄) emissions from rice fields were determined using automated measurement systems in China, India, Indonesia, Thailand, and the Philippines. Mitigation options were assessed separately for different baseline practices of irrigated rice, rainfed, and deepwater rice. Irrigated rice is the largest source of CH₄ and also offers the most options to modify crop management for reducing these emissions. Optimizing irrigation patterns by additional drainage periods in the field or an early timing of midseason drainage accounted for 7–80% of CH₄ emissions of the respective baseline practice. In baseline practices with high organic amendments, use of compost (58–63%), biogas residues (10–16%), and direct wet seeding (16–22%) should be considered mitigation options. In baseline practices using prilled urea as sole N source, use of ammonium sulfate could reduce CH₄ emission by 10–67%. In all rice ecosystems, CH₄ emissions can be reduced by fallow incorporation (11%) and mulching (11%) of rice straw as well as addition of phosphogypsum (9–73%). However, in rainfed and deepwater rice, mitigation options are very limited in both number and potential gains. The assessment of these crop management options includes their total factor productivity and possible adverse effects. Due to higher nitrous oxide (N₂O) emissions, changes in water regime are only recommended for rice systems with high baseline emissions of CH₄. Key objectives of future research are identifying and characterizing high-emitting rice systems, developing site-specific technology packages, ascertaining synergies with productivity, and accounting for N₂O emissions.     

秸秆堆肥腐殖土PRB修复地下水硝酸盐污染研究

比较不同比例的秸秆堆肥腐殖土与细砂组成的介质对修复地下水硝酸盐污染的影响,研究秸秆堆肥腐殖土PRB(permeable reactive barrier,可渗透反应墙)去除地下水硝酸盐污染的效果。结果表明,以秸秆堆肥腐殖土作为介质的PRB对硝酸盐具有很高的去除率,可使受到硝酸盐污染的地下水经处理后达到地下水质量Ⅲ类标准;增加秸秆堆肥腐殖土所占比例,会提高PRB对硝酸盐的去除率,但装置运行初期的修复效果较差。     

A Biosolids Composting Challenge: Meeting Demand for a Peat-Free Horticultural-Grade Product

In 1996, Thames Water launched a range of peat-free compost products based on biosolids. In order to keep up with demand and to maintain the high standards of product quality, the company has investigated higher-rate composting processes and optimisation of the maturation stage. Agitated-bay composting systems are the preferred in-vessel technology for large sludge treatment centres using woodchip as a bulking agent. These automated systems (i) accelerate the composting process, (ii) maximise throughput on a smaller footprint, and (iii) achieve better control of odour emissions.
A maturation trial with composted material from the US Filter agitated-bay system confirmed that a horticultural-grade product could be attained. Small-scale maturation trials showed that seeding with mature green waste compost can accelerate nitrification to such a rate that near zero levels of ammonia can be achieved after one month of maturation.     

蘑菇渣资源的生态高值化利用研究进展

蘑菇渣是食用菌产业的固体废物,磨菇渣中含有食用菌的代谢产物:包括糖类、有机酸类、酶和生物活性物质,数量庞大的微生物群落以及残留的菌丝体,蘑菇渣具有生态高值化利用的潜力,结合国内外文献,介绍了磨菇渣在农业与生态环境修复领域应用研究进展。     

城市生活垃圾堆肥腐熟度综合指标的确定

腐熟度参数及其指标是评价堆肥过程及堆肥产品质量的重要尺度。腐熟度指标可分为三类：物理学指标、化学指标和生物学指标。目前还没有一种公认的堆肥腐熟度指标。通过系统分析现有堆肥腐熟度指标的特点及局限,讨论了建立垃圾堆肥腐熟度综合判断的必要性和可行性,提出了以C／N、比耗氧速率(SOUR)、NH4^-N为指标建立堆肥腐熟度综合评价方法。     

Effect of compost and soil properties on the availability of compost phosphate for white clover (Trifolium repens L.)

Wide variation in results exists in the literature on the effectiveness of composts to sustain the phosphorus (P) nutrition of crops. The aim of this work was to assess the importance of some soil and composts properties on the utilization of compost-P by white clover (Trifolium repens L.). This study was carried out with samples collected from four composts made from solid kitchen and garden wastes, and with two soil samples taken from the A horizon of a P-rich sandy acidic Dystrochrept and of a P-limited clayey calcareous Eutrochrept. Changes in the amount of inorganic P (Pi) isotopically exchangeable within 1 min (E_1min) were measured during 32 weeks in incubated soil-composts or soil-KH₂PO₄mixtures where P sources had been added at the rate of 50 mg P kg^–1 soil. Uptake of compost-P or KH₂PO₄-P by white clover was measured on the same amended soils during 16 weeks. In both soils, the application of composts resulted after 32 weeks of incubation in E_1min values ranging between those observed in the control without P and those observed in the KH₂PO₄treatment, i.e., in values ranging between 4.2 and 5.9 mg P kg^–1 in the sandy acidic soil and between from 1.6 to 4.3 mg P kg^–1 in the clayey calcareous soil. The total coefficient of utilization of compost-P (CU-P) by white clover reached values in both soils for the four composts ranging between 6.5% and 11.6% of the added P while in the presence of KH₂PO₄ the CU-P reached values ranging between 14.5% in the clayey calcareous soil and 18.5% in the sandy acidic soil. Results obtained in the sandy acidic soil suggest, that white clover initially used a fraction of the rapidly exchangeable compost P, while at a latter stage plant roots enhanced the mineralisation of compost organic P and took up a fraction of the mineralized P. These relations were not observed in the clayey calcareous soil probably because of its high sorbing capacity for P. In the sandy acidic soil, composts application increased the uptake of soil P by the plant from 31.4 mg P kg^–1 soil in the control without P to values ranging between 37.9 to 42.7 mg P kg^–1 soil in the presence of composts. This indirect effect was related to a general improvement of plant growth conditions in this soil induced by compost addition (from 9.9 g DM kg^–1 soil in the control without P to values ranging between 14.0 to 16.1 g DM kg^–1 soil in the presence of composts) and/or to the release of Al- or Fe bound soil P to the solution due to soil pH increase following compost application. Finally the total coefficient of utilization of P (CU-P) derived from KH₂PO₄ and composts was related to the total amount of N exported by white clover in the P-limited clayey calcareous soil but not in the P-rich sandy acidic soil. This suggests that in a soil where N₂ biological fixation is limited by low P availability, the CU-P of a compost by white clover is not only related to the forms of P present in the compost but also to its effect on N nutrition. However, it is not clear whether this improved N nutrition was due to compost mineralisation, or to an indirect compost effect on the N₂ biological fixation.     

城市垃圾堆肥处理厂技术经济评价指标

《城市生活垃圾堆肥处理厂技术经济评价指标》课题研究成果表明：堆肥厂技术经济评价指标是一个含综合性指标和专项指标；建设指标和运营指标；货币指标和实物指标的完整指标体系；是城市环境卫生行业技术标准体系的一个重要组成部分；是设计、建设、管理城市生活垃圾堆肥处理厂的重要科学依据．     

Compost bedded pack dairy barn management,performance, and producer satisfaction

The objective of the research was to characterize herd performance, producer satisfaction and recommendations, and management practices used by compost bedded pack (CBP) managers in Kentucky (42 farms and 47 CBP facilities). Farms were visited between October 2010 and March 2011. A random selection of cows housed solely in the CBP were scored for locomotion and hygiene. Changes in monthly Dairy Herd Improvement Association performance records, including milk production, SCC, reproductive performance, and daily bulk-tank somatic cell count after moving into the CBP were analyzed using the MIXED procedure of SAS (SAS 9.3; SAS Institute Inc., Cary, NC). The GLM procedure of SAS (SAS 9.3) was used to develop models to describe CBP moisture, CBP temperature at 20.3 cm, and mean herd hygiene. Producers provided 9.0 ± 2.2 m² of pack space per cow (n = 44). Barns constructed with an attached feed alley cost $1,051 ± 407 per cow (n = 40). Barns constructed without an attached feed alley cost $493 ± 196 per cow (n = 13). Kiln-dried shavings required 0.05 ± 0.04 m³ of bedding per cow per day (n = 15). Green shavings required 0.07 ± 0.06 m³ of bedding per cow per day (n = 12). The most-frequently cited benefits of the CBP included cow comfort (n = 28), cow cleanliness (n = 14), and the low-maintenance nature of the system (n = 10). Increased stirring frequency, stirring depth, and ambient temperature increased pack temperature, measured at 20.3 cm below the CBP surface. Increased stirring depth, pasture-adjusted space per cow, and drying rate decreased CBP moisture. Mean herd locomotion and hygiene scores were 1.5 ± 0.3 (n = 34) and 2.2 ± 0.4 (n = 34), respectively. Increased 20.3-cm depth CBP temperature and ambient temperatures improved mean herd hygiene. Bulk-tank somatic cell count decreased from the year before to the year after moving into the CBP barn (323,692 ± 7,301 vs. 252,859 ± 7,112 cells/mL, respectively) for farms using the CBP barn as the primary housing facility (n = 9). Daily milk production, collected from monthly Dairy Herd Improvement Association tests, increased from before moving into the CBP barn to the second year after (29.3 ± 0.3 vs. 30.7 ± 0.3 kg, respectively) for farms using the CBP barn as the primary housing facility (n = 8). Calving interval decreased from the year before to the second year after (14.3 ± 0.1 vs. 13.7 ± 0.1 mo) moving into the CBP barn for farms using the CBP as primary housing (n = 8).