城市生活垃圾填埋场可生物降解物降解产物量化分析

我国是世界上生活垃圾产生量和堆存量最大的国家,垃圾污染问题十分严重.目前,城市垃圾处理手段主要有填埋、焚烧与堆肥.在生活垃圾的资源化研究中,最为突出的就是有机垃圾的厌氧消化技术.厌氧消化与好氧堆肥相比,它具有过程可控制、降解快、能量再利用等优点.欧洲近十年来积极开发这一新的垃圾处理技术,并已取得生产试验成功,每年大约有106t的垃圾通过厌氧消化得到处理.生活垃圾厌氧消化存在两大问题:①填埋气;②渗滤液.填埋气热值很高,20000kJ/m3,是很好的气态燃料,可用于发电.本课题中主要研究填埋气产量和产气速率,影响产沼气因素,如何提高填埋气产气速率.我国近些年在城市有机垃圾厌氧消化产沼气方面也做了一些初步研究,如垃圾填埋场有机污染物的生物降解机理,垃圾填埋场气体产生和模型研究,高温厌氧消化处理城市有机垃圾的正交试验研究,城市有机垃圾厌氧消化痕量激活剂的促进作用及产能研究等等.     

厌氧消化技术在日本有机废水和废弃物处理中的应用

日本污泥厌氧消化始于1932年,目前污泥厌氧消化工程已超过300个,消化池总容积达210×10<'4>m<'3>.目前,全日本共有300多座升流式厌氧污泥床反应器(upflow anaerobic sludgebed,UASB)和膨胀颗粒污泥床(expanded granular sludge bed,EGSB)处理厂,主要用于包括啤酒废水、软饮料废水、酿酒废水、食品加工废水和化工废水在内的高浓度有机工业废水的处理.总结了厌氧消化技术在日本有机废水和有机废弃物处理中的应用状况,以及运行参数.此外,对日本厌氧消化技术在厌氧膜生物反应器、产氢产甲烷两段发酵和沼气生物脱硫等方面的新进展也进行了介绍.     

餐厨垃圾全物料湿式厌氧消化产沼技术的工程应用

杭州市萧山区某餐厨垃圾厌氧消化处理项目设计处理能力为餐厨垃圾200 t/d、地沟油20 t/d。采用预处理+厌氧消化+沼气利用的主流工艺路线。根据功能定位,系统分为预处理系统、地沟油提纯系统、厌氧消化及脱水系统、污水处理系统、沼气净化及利用系统以及辅助生产系统等6大系统。餐厨垃圾通过预处理后形成油脂、有机浆液、固渣三股物料,油脂与地沟油提纯后的油脂作为毛油对外销售;有机浆液与固渣一并进行厌氧消化;厌氧消化产生的沼气在厂内净化后部分用作锅炉燃料,部分发电上网。项目工程总投资15 386.43万元,约合69.8万元/t。项目达产后,运行效果良好,CSTR湿式厌氧消化运行稳定,全量厌氧时产气率高、出水水质好。     

厌氧消化在餐厨垃圾处理中的应用分析

餐橱垃圾在现代社会生活垃圾中所占份额极大,对其进行环保刻循环胡处理是社会关注的重点,厌氧消化被公认为当前餐橱垃圾处理中最为环保的有机处理方法.本文从分析我国餐橱垃圾的处理现状入手,进而探讨了厌氧消化的基本概况和处理过程,研究了厌氧消化巍橱垃圾处理中的优势,阐述述了厌氧消化应用于餐厨垃圾的前景.     

铁刨花投量对餐厨垃圾和污泥协同厌氧消化的影响

餐厨垃圾和城市污泥是两种不同来源的有机固废,为提高这两种有机固废的协同厌氧消化效率,添加了来自机械加工厂的废弃物铁刨花,考察其对有机固废厌氧消化产甲烷和产气量的影响。结果表明:随着铁刨花投加量的增大,进入稳定产甲烷阶段所需时间缩短。当铁刨花投加量为25 g/L时,最高甲烷浓度、最高日产气量、累积产气量比对照组分别提高了33%、74%、120%,氨氮浓度在第15天比对照组降低了21%。在原有消化条件下,投加适量铁刨花有助于提高产气效果,增强系统运行的稳定性。     

谈污泥厌氧消化预处理方法

结合传统的污泥厌氧消化周期长、消化速率低的特点,综述了热、化学、生物和机械预处理方法及其在研究中对污泥厌氧消化的影响,并提出厌氧消化预处理方法的展望,以期改善污泥理化性质,提高厌氧消化效率。     

城市污水处理厂污泥的好氧处理研究

为了实现污泥的稳定化、减量化和无害化,对城市污水处理厂的浓缩污泥和厌氧消化污泥进行了好氧处理试验研究.试验结果表明,污泥好氧处理使污泥中有机物质含量降低,臭味减小.厌氧污泥经好氧消化处理后,一方面使污泥得到稳定化和减量化;另一方面,可以把污泥中的致病菌杀死.污泥经好氧消化后沉降性能有明显提高,絮凝剂的加入使其脱水性能也得到一定的改善.     

污泥高级厌氧消化的应用现状与发展趋势

对污泥高级厌氧消化的技术发展动力进行了分析,指出了提高能源效率、污泥品质、脱水性能、消化性能及运行效果是高级厌氧消化发展的主要动力。对高温消化、两相消化、延时消化、协同消化及热水解+消化等几种高级厌氧消化技术进行了介绍,分析了这几种技术的优、缺点和工艺发展的各种变型。最后对高级厌氧消化技术的发展前景进行了展望。     

超声破解促进污泥高温厌氧消化研究

城市污水厂的剩余污泥经槽式超声波反应器预处理后,被投加到小型高温厌氧反应器中进行消化处理,通过改变投配率来控制厌氧消化时间,研究超声破解对高温厌氧消化反应速率和效率的影响。试验结果表明,与未经预处理的污泥相比,超声破解能够明显提高污泥高温厌氧消化的生物气产量及对有机物的去除率。控制组在停留时间为20d时对TCOD的去除率为37.29%,而破解污泥在第8天时的去除率就达到了39.60%。这表明污泥经超声破解后其厌氧消化性能得到改善,超声破解不但可以提高厌氧消化对有机物的去除率,而且可以缩短反应时间,在不影响厌氧消化反应正常进行的条件下,还实现了污泥的减量化。     

`热水解对污泥高温厌氧消化产气及群落结构的影响

针对剩余污泥厌氧消化效率及产气量低的问题,采用热水解(THP)技术对剩余污泥进行预处理,然后进行55℃高温厌氧消化,考察对产气性能及微生物群落结构的影响。THP预处理可以有效提高剩余污泥高温厌氧消化的产气性能,在反应时间为16 d时,厌氧消化总产气量增加了39.14%;反应时间为8 d时,厌氧消化产气量提高了36.36%。经THP预处理后,厌氧消化系统功能微生物的多样性略有下降,群落的丰富度指数由未经THP预处理的2.32降为1.81;但系统微生物的群落组成及优势微生物的数量均发生了明显变化,群落结构的变化是厌氧消化产气量增加的微生物学基础。     

Effects of ionizable organic compounds in different species on the sorption of p-nitroaniline to sediment

In natural water systems, sorption of an organic pollutant to soil/sediment is often influenced by coexisting organic compounds. For ionizable organic compounds, molecular form may do differently competitive effect from ionic form. In order to examine competitive power of ionizable organic compounds in different forms, effects of some ionizable organic compounds including organic acids and organic bases in molecular form or ionic form on the sorption of p-nitroaniline to a sediment from water were investigated by batch equilibrium experiments. Results exhibit that molecular organic acids are much stronger in competitive power to p-nitroaniline than ionic ones, while ionic ones of organic bases compete with p-nitroaniline stronger than molecular ones. In addition, the competitive powers of coexisting organic acids in molecular form or ionic form in binary-solute systems are good correlated with the nonlinear sorption of cosolutes in single-solute systems, i.e., the stronger nonlinear sorption of the cosolute in single-solute systems, the stronger competitive effect of the cosolute on p-nitroaniline is showed in binary-solute systems. For organic amines, organic cations could be adsorbed through cationic exchange to the sediment more favorably than their molecular forms, and consistently, the former shows stronger competitive power than the latter. These results are of significance for one to describe accurately sorption of ionizable organic compounds in natural environment.     

有机共同体思想的生成、实现及意义探析

有机共同体主义在有机哲学的基础上系统地回答了有机马克思主义关于有机共同体的生成、实现及现实意义的基本问题。有机共同体主义指出资本主义生产方式的反生态性,认为“现代性”思维是造成生态危机的深层次根源,对日益严峻的环境与生态问题的关注与反思是其思想产生的直接原因。有机共同体主义的核心价值在于实现人类、自然和社会的和谐统一。有机共同体主义主张培育和践行共同体主义价值观,坚持通过生态文明建设来实现人与自然的共同福祉。有机共同体主义的现实意义表明,有机共同体理念有利于铸牢人类命运共同体意识,实现整个人类的合作共赢,并逐步迈向生态文明。     

Monitoring of the evolution of an industrial compost and prediction of some compost properties by NIR spectroscopy

Sewage treatment plants produce wastes resulting from the organic matter concentration in the form of sludge. A way of jointly treating and exploiting these increasing wastes jointly is the composting. Composting makes it possible to reduce volumes and the masses of wastes all while developing them in a product usable like organic soil enrichment. In this work, the composting process of an industrial sewage sludge composting plant was monitored to study the evolution of different physico-chemical parameters (temperature, moisture, pH, organic carbon, organic and inorganic nitrogen, organic carbon/organic nitrogen ratio, humic substances) and biochemical parameters (soluble fraction, hemicellulose, cellulose, lignin). Because these analyses are expensive and time consuming, we wanted to develop an alternative method to determine the maturity of compost related to compost properties with raw samples. Acceptable predictions were found for moisture, temperature, pH, organic carbon, organic carbon/organic nitrogen ratio, total-, organic- and ammoniacal nitrogen, fulvic- and humic acids and fulvic acids/humic acids ratio, but the error values were too high for the compost age to consider a quantification model. With regard to the biochemical parameters, this study is rather a preliminary test which shows the interest of the approach, but requires to be continued. Finally, the age of compost can be evaluated with Principal Component Analysis applied to NIR spectra.     

Batch adsorption of organic pollutants from oxidation pond effluents using fly ashes

The batch shaking adsorption study was conducted to determine the potential of fly and volcanic ashes in removing organic pollutants from oxidation pond effluents. Factors affecting organic pollutant removals, such as concentrations and sizes of fly and volcanic ashes, initial pond effluent organic concentrations, washed and unwashed conditions of fly and volcanic ashes, were investigated. The TOC (total organic carbon) removal efficiency varied from 30 to 58 percent. The organic removal efficiency increased with increasing ash concentrations, with decreasing initial pond effluent organic concentrations and with decreasing sizes of ashes.     

“显性与隐性”,有机更新再探索——以长沙市麓山南路两厢改造为例

摘 要:结合麓山南路两厢改造的实例,以全新视角对有机更新理论进行深层次解读,将有机更新过程中涉及到的各种要素归纳为“显性有机要素”和“隐性有机要素”两大类,并以此作为理论出发点,探索有机更新理论在不同类型旧城改造中的运用模式.     

Formation of organic chloramines during water disinfection - chlorination versus chloramination

Many of the available studies on formation of organic chloramines during chlorination or chloramination have involved model organic nitrogen compounds (e.g., amino acids), but not naturally occurring organic nitrogen in water. This study assessed organic chloramine formation during chlorination and chloramination of 16 natural organic matter (NOM) solutions and 16 surface waters which contained dissolved organic nitrogen (DON). Chlorination rapidly formed organic chloramines within 10 min, whereas chloramination formed organic chloramination much more slowly, reaching the maximum concentration between 2 and 120 h after the addition of monochloramine into the solutions containing DON. The average organic chloramine formation upon addition of free chlorine and monochloramine into the NOM solutions were 0.78 mg-Cl₂/mg-DON at 10 min and 0.16 mg-Cl₂/mg-DON at 24 h, respectively. Organic chloramine formation upon chlorination and chloramination increased as the dissolved organic carbon/dissolved organic nitrogen (DOC/DON) ratio decreased (i.e., DON contents increased). Chlorination of molecular weight (10,000 Da) fractionated water showed that molecular weight of DON would not impact the amount of organic chloramines produced. Comparison of three different disinfection schemes at water treatment plants (free chlorine, preformed monochloramine, and chlorine/ammonia additions) indicated organic chloramine formation could lead to a possible overestimation of disinfection capacity in many chloraminated water systems that add chlorine followed by an ammonia addition to form monochloramine.     

Buffering of recovery from acidification by organic acids

In the United Kingdom, as in other regions of Europe and North America, recent decreases in surface water sulphate concentrations, due to reduced sulphur emissions, have coincided with marked increases in dissolved organic carbon (DOC) concentrations. Since many of the compounds comprising DOC are acidic, the resulting increases in organic acidity may have the potential to offset the benefits of a decrease in mineral (sulphate) acidity. To test this, we used a triprotic model of organic acid dissociation to estimate the proportional organic acid buffering of reduced mineral acidity as measured in the 22 lakes and streams monitored by the UK Acid Waters Monitoring Network. For an average non-marine sulphate decrease of 30 mueq l(-1) over 15 years from 1988-2003, we estimate that around 28% was counterbalanced by rising strong organic acids, 20% by rising alkalinity (partly attributable to an increase in weak organic acids), 11% by falling inorganic aluminium and 41% by falling non-marine base cations. The situation is complicated by a concurrent decrease in marine ion concentrations, and the impact this may have had on both DOC and acidity, but results clearly demonstrate that organic acid increases have substantially limited the amount of recovery from acidification (in terms of rising alkalinity and falling aluminium) that have resulted from reducing sulphur emissions. The consistency and magnitude of sulphate and organic acid changes are consistent with a causal link between the two, possibly due to the effects of changing acidity, ionic strength and aluminium concentrations on organic matter solubility. If this is the case, then organic acids can be considered effective but partial buffers to acidity change in organic soils, and this mechanism needs to be considered in assessing and modelling recovery from acidification, and in defining realistic reference conditions. However, large spatial variations in the relative magnitude of organic acid and sulphate changes, notably for low-deposition sites in northwestern areas where organic acid increases apparently exceed non-marine sulphate decreases, suggest that additional factors, such as changes in sea-salt deposition and climatic factors, may be required to explain the full magnitude of DOC increases in UK surface waters.     

Mechanistic and kinetic evaluation of organic disinfection by-product and assimilable organic carbon (AOC) formation during the ozonation of drinking water

Ozonation of drinking water results in the formation of low molecular weight (LMW) organic by-products. These compounds are easily utilisable by microorganisms and can result in biological instability of the water. In this study, we have combined a novel bioassay for assessment of assimilable organic carbon (AOC) with the detection of selected organic acids, aldehydes and ketones to study organic by-product formation during ozonation. We have investigated the kinetic evolution of LMW compounds as a function of ozone exposure. A substantial fraction of the organic compounds formed immediately upon exposure to ozone and organic acids comprised 60-80% of the newly formed AOC. Based on experiments performed with and without hydroxyl radical scavengers, we concluded that direct ozone reactions were mainly responsible for the formation of small organic compounds. It was also demonstrated that the laboratory-scale experiments are adequate models to describe the formation of LMW organic compounds during ozonation in full-scale treatment of surface water. Thus, the kinetic and mechanistic information gained during the laboratory-scale experiments can be utilised for upscaling to full-scale water treatment plants.     

The Use of Biosolids and Other Organic Substances in the Creation of Soil-Forming Materials

This paper describes an experiment which was carried out at a landfill site in north Lincolnshire to investigate the use of biosolids and other organic materials in soil formation. The following organic amendments were incorporated into the surface of the on-site geological clay to form 'topsoil'treatments: (i) nil, (ii) biosolids (digested cake), (iii) waste peat/compost, and (iv) composted green waste. The biosolids were applied at a rate of 70 tDS/ha and all the organic materials were incorporated to a depth of 150 mm. The organic amendments reduced the topsoil bulk density and increased plant available water supply and soil water infiltration rates. Topsoil organic matter, total nitrogen and extractable phosphorus concentrations, biomass nitrogen, readily mineralisable organic nitrogen and soil respiration rates were also increased. Additionally, the biosolids application increased topsoil aggregate stability and soil surface strength.     

Effects of molecular weight of natural organic matter on cadmium mobility in soil environments and its carbon isotope characteristics

We investigated the role of natural organic matter in cadmium mobility in soil environments. We collected the dissolved organic matter from two different types of natural waters: pond surface water, which is oxic, and deep anoxic groundwater. The collected organic matter was fractionated into four groups with molecular weights (unit: Da (Daltons)) of <1 x 10(3), 1-10 x 10(3), 10-100 x 10(3), and >100 x 10(3). The organic matter source was land plants, based on the carbon isotope ratios (delta(13)C/(12)C). The organic matter in surface water originated from presently growing land plants, based on (14)C dating, but the organic matter in deep groundwater originated from land plants that grew approximately 4000 years ago. However, some carbon was supplied by the high-molecular-weight fraction of humic substances in soil or sediments. Cadmium interacted in a system of siliceous sand, fractionated organic matter, and water. The lowest molecular weight fraction of organic matter (<1 x 10(3)) bound more cadmium than did the higher molecular weight fractions. Organic matter in deep groundwater was more strongly bound to cadmium than was organic matter in surface water. The binding behaviours of organic matter with cadmium depended on concentration, age, molecular weight, and degradation conditions of the organic matter in natural waters. Consequently, the dissolved, low-molecular-weight fraction in organic matter strongly influences cadmium migration and mobility in the environment.