Effect of Poly(Vinyl Alcohol) and Polyethylene on the Growth of Red Pepper and Tomato

Poly(vinyl alcohol) (PVA) and polyethylene (PE) were blended with a soil for cultivation, and their effects were investigated on the growth behavior of red pepper and tomato by examining the stems, the leaves, and the roots. PVA retarded the growth of red pepper significantly even at a concentration as low as 0.05%. The roots were depauperated more than the stems and the leaves. Tomato was also affected by PVA but to a lesser extent than red pepper. In contrast, the presence of both round pieces (10 mm diameter) of PE film and powdery PE influenced negligibly the growth of red pepper as well as that of tomato up to 35 wt% in soil.     

加拿大污泥资源化利用和工程实践对中国的借鉴

以埃德蒙顿市为例,介绍了加拿大污泥资源化利用的主要模式及工程实践;并在此基础上着重介绍其污泥堆肥技术和从污泥液体中提取营养元素制取绿色缓释肥料Crystal Green的新工艺,旨在为国内城市污水处理厂污泥的回收利用提供借鉴。中国是一个以农业为主的发展中大国,污泥处理应当以堆肥、土地利用和资源化为主。管理上,需要规范中国的污泥处置工作,逐步提高资源化利用率;技术上,应重视城市污水污泥厌氧处理新工艺的开发,综合利用引进、消化吸收加拿大等发达国家的污泥堆肥一体化技术。     

污泥膜覆盖好氧发酵堆乍流场模拟及应用研究

运用Gambit软件建立了污泥好氧发酵堆体的多孔介质模型,通过自行设计的实验装置获得了堆体的通风粘性阻力系数和惯性阻力系数以及功能膜压差与透气量之间的关系,用Fluent软件分析了堆体不同截面形状及底部通风管数量对堆体通风均匀性的影响,为确定合理的通风管数量及截面几何形状提供理论依据。对上海奉贤区城镇污水厂污泥处理工程发酵仓进行堆体流场模拟,确定堆体采用小拱形截面形状,堆高2m,宽8m,底部设置4条通风管,实际运行效果良好。     

Assessment of Human and Ecosystem Risk Due to Agricultural Waste Compost Application on Soils: A Review

Agricultural wastes (AW) are often characterized by varying pH and substantial contamination potential, which are mainly related to their high organic load, thus affecting—when improperly disposed of—soils, living organisms, and water bodies. Composting of AW is the most commonly used management option and results in the production of soil improver that enhances crop growth and contributes to agricultural sustainability. This study aims to present the framework for assessing human and ecosystem risk when compost produced from AW is applied on soil. In order to develop this framework, issues such as origin, composition and pre-treatment of AW, application rates on soils, bioavailability and mobility of contaminants present in compost, exposure routes and rates as well as determination of the fate of contaminants in soil, air, and water, should be taken into consideration.     

Effects of the inhibitor of pyruvate dehydrogenase multi-enzyme complex on hydrogen production by fermentative microbes

The redox state of carbon sources directly affected the ratio of NADH/NAD⁺ which was coupled to the hydrogen production by Bacillus sp. FS2011. The addition of the inhibitor of pyruvate dehydrogenase multi-enzyme complex (PDHc)E1 could regulate hydrogen production by FS2011 or pretreated compost in batch cultivation. With the addition of appropriate amount of inhibitor, hydrogen production via the NADH pathway was increased, leading to the higher overall hydrogen production. The maximum hydrogen yields of 307.6 ± 13.21 mL/g by FS2011 with the inhibitor of 80 ppm and 362.1 ± 10.1 mL/g by pretreated compost with the inhibitor of 60 ppm were observed, which were increased by 8.7% and 17.8% compared with the controls, respectively. Meanwhile the production of soluble metabolic byproducts such as butyrate, acetate and so on were decreased, resulting in reducing the difficulty of wastewater treatment.     

硫磺和硫酸亚铁对鸡粪好氧堆肥的保氮效果

利用堆肥反应器控制堆肥条件,研究外源添加剂硫磺和硫酸亚铁在鸡粪好氧堆肥中的保氮效果。结果表明：与无添加剂的对照（CK）比较,堆肥中添加硫磺（T1）对堆肥升温和高温期的维持有一定影响,添加硫酸亚铁（T2）对堆肥升温和高温期的维持均无显著影响,而同时添加硫磺和硫酸亚铁（T3）更有利于高温期的持续,加速有机物的降解。添加硫磺...     

嗜热真菌的生物转化功能与经济价值

嗜热真菌是经济微生物中极为重要的一个类群,许多兼性嗜热真菌可在常温和一般高温条件下生存,它们在有机物质的生物转化和物质循环中起着重要的作用。对嗜热真菌在蘑菇培养料的制备、废物的堆肥化处理、酒曲制作等几种常见生产过程中的生物转化作用和机理进行分析,探讨嗜热真菌在人类生产活动中的作用及经济价值。     

Characteristics of night soil and leaf co-composting using aerobic static method

The main purpose of this work is to investigate the characteristics of night soil and leaf co-composting using aerobic static composting method. Three influencing factors, including proportion of night soil and leaf, aeration rate and aeration pattern, were investigated through the evolution of the principal physicochemical properties, i.e., temperature, oxygen consumption rate, organic matters, moisture content, carbon, nitrogen, carbon-to-nitrogen ratio and Germination index (GI). It was found that the 3∶1 (w∶w) mixture of night soil and leaf was capable of achieving the highest composting temperature, longest retention time of high temperature (55°C), and fastest organic matter degradation. The 0.14 m³·min^-1·m^-3 aeration rate was most beneficial to composting, and the mixture of night soil and leaf maintained the highest temperature for the longest duration and achieved the highest CO₂ content and GI. The continuous aeration pattern during composting was superior to an intermittent aeration pattern, since the latter delayed the composting process.     

有机生活垃圾不同微生物接种工艺堆肥腐熟度评价

选取含水率、发芽指数、C/N、水溶性碳、氨态氮5项为评价指标,运用属性识别法、灰色关联分析法、模糊综合评价法,分别对微生物接种几种不同工艺(T1为两阶段接种,T2为前阶段接种,T3为多阶段接种,CK为不接种)的堆肥腐熟度进行了评价.结果显示,在堆肥周期内3种评价方法相一致的结果是自然堆肥(CK)归入未腐熟等级、多阶段接种堆肥(T3)归入腐熟等级,表明根据堆肥温度变化情况加入多种外源微生物加速了堆肥过程中的物质转化,更有利于腐殖化的进程,提高了堆肥效率;而T1、T2处理3种评价方法给出了不同的结果.对3种评价方法进行比较显示,灰色关联分析法较模糊综合评价法、属性识别法划分幅度小、更加精准,是堆肥评价的一种较优方法.      

基于不同目标的大型生活垃圾堆肥处理工艺的优选

以北京市南宫堆肥厂为例,利用模糊数学和层次分析法对10种堆肥处理工艺进行了比较研究.结果表明,以腐熟度指标为单目标的最优堆肥工艺:以0~80mm生活垃圾为堆肥原料,高温发酵8d,在第4d时翻堆破碎1次,后熟化12d最终熟化12d;以经济指标为单目标的最优堆肥工艺:以0~80mm生活垃圾为堆肥原料,高温发酵8d,后熟化12d,最终熟化12d;以腐熟度指标和经济指标为双目标的最优堆肥工艺:采用0~80mm生活垃圾为物料,高温发酵8d其中翻堆破碎1次,后熟化12d,最终熟化12d.