污泥焚烧灰渣无害化处理及其资源化利用技术研究

污水厂污泥焚烧是一种有效的减量化处理方式,焚烧产生的污泥焚烧灰渣通常被运到填埋场进行填埋处置.根据污泥灰渣的物理特性,对其进行了急性毒性分析和水化活性分析,并经过无害化处理的污泥焚烧灰渣寻找到了使其资源化利用的新方法,即固化后制成的路基材料.用该法制成的路基材料抗压强度满足规定的技术要求,同时,重金属浸出毒性也满足国家固体废物排放标准的要求.     

污泥焚烧工程中的磷形态分布与磷迁移研究

以竹园污泥焚烧工程为依托,采用SMT方法研究磷在干污泥、炉渣和飞灰中的含量及赋存形态。结果表明,焚烧过程使炉渣及飞灰中的总磷(TP)含量比干污泥提高了2~3倍,还使其中的无机磷(IP)含量大幅提升至TP总量的99%以上,在实现磷富集的同时有效提升了磷的生物可利用性。分析焚烧过程对磷灰石无机磷(AP)和非磷灰石无机磷(NAIP)的影响,发现镁离子与钙离子会与污泥中的NAIP发生反应,取代铝离子从而生成钙镁结合形式的AP;与炉渣相比,飞灰在布袋处受CaO添加的影响,此种转化趋势更为明显,AP已经超过NAIP成为优势形态,占IP总量的78.4%。焚烧是上海地区处理污泥的主要方式,该研究结果从营养物回收角度为污泥焚烧飞灰的资源化利用提供了新思路。     

Impact in Scotland of UK and EC Sewage Legislation

The EC Directive (91/271/EEC) concerning urban waste water treatment has far-reaching financial and technological implications for local authorities in Scotland which are responsible for sewerage. Increased capital consent limits and additional financial assistance from central government are essential if the requirements of the legislation are to be met.
Although the Directive is welcomed in general terms, the sections of the legislation dealing with the identification of sensitive waters and the provision of primary treatment for coastal discharges to less sensitive waters are of limited environmental significance in Scotland.
The elimination of sewage sludge disposal at sea will create severe difficulties for Scottish authorities as a high percentage of sewage sludge is currently disposed of at sea. Each of the main alternative disposal options presents environmental, financial and technical problems and, in the case of incineration, the certainty of widespread unpopularity with the public.     

Platinum-group elements in sewage sludge and incinerator ash in the United Kingdom: Assessment of PGE sources and mobility in cities

Platinum-group element (PGE) concentrations in sewage sludge and incinerator ash compared with average PGE concentrations in road dust show a common pattern, characterized by a negative Rh anomaly. This similarity, found at 9 UK incinerators, suggests that there is a universal characteristic PGE pattern produced by common processes of dispersal of Pt, Pd and Rh derived from automobile catalytic converters.Ninety-one sewage sludge and incinerator ash samples from the sewage treatment facilities in Sheffield, Birmingham and 7 other UK cities were analyzed for PGE. The highest concentrations are 602 ppb Pt and 710 ppb Pd with lower maximum concentrations of 65 ppb Rh, 100 ppb Ru, 33 ppb Ir and 12 ppb Os. Ash from incinerated sewage was found to have higher PGE concentrations compared to the original sludge and the PGE ratios are preserved during incineration.Rh is more mobilized and dispersed than the other PGE as it is transported from roads into the drainage system and into sewage. Pt/Pd ratios of 1.0 in road dust and 0.9 in sewage and incinerator ash suggest that Pd is more mobile than Pt during dispersal. PGE abundances in stored incinerator ash of varying ages appear to have been affected by the variation in use of Pt, Pd and Rh in catalytic converters due to variation in their market prices.Concentrations of Os, Ir and Ru in ashes are greater in Sheffield and London than all the other city sites and may be derived from point industrial sources.     

城镇污水污泥的处理处置现状分析

根据我国污水污泥的处理情况,分析了填埋、填海、焚烧、堆肥、建材资源化等污泥处置方式的优缺点,认为填埋、填海、堆肥、焚烧等处置方式未来将会受到更多的限制,而建材资源化利用将会成为污泥处置的重要方式。     

循环流化床一体化污泥焚烧工程的调试及分析

为探索采用焚烧工艺处理污水厂剩余污泥的可行性,在杭州市七格污水处理厂建设了规模为100 t/d的污泥焚烧处理示范工程,并进行了冷、热态调试。冷态调试结果表明,系统关键设备如干污泥螺旋输送机、焚烧炉、复合干化器等的测试数据与设计值吻合。热态调试结果显示,复合干化器内温度均匀,含水率为79%～80%的湿污泥在复合干化器内破碎和干燥程度良好,干污泥颗粒最大直径为3 mm5,0%的切割粒径为0.32 mm。干污泥即时进入循环流化床焚烧炉焚烧,焚烧温度为860℃。可见,采用循环流化床一体化焚烧技术处理污泥在工程上是可行的。     

垃圾焚烧灰渣的特性及资源化利用

随着经济的发展和人民生活水平的提高,垃圾问题日益突出。焚烧在我国某些城市逐渐开始成为主要的生活垃圾处理方法之一,同时,焚烧过程产生的副产物的二次污染及其性质渐受关注。通过对城市生活垃圾焚烧灰渣的特性研究分析,用X射线荧光光谱仪对垃圾灰渣进行成分分析,为垃圾焚烧灰渣的资源化利用奠定了基础。     

城镇污水厂污泥与煤混烧发电的技术经济分析

城镇污水厂污泥与煤混烧发电是污泥减容和资源化的有效方法.污泥千化工艺灵活,干化污泥可燃性好,发电运行成本低.采用汽轮机抽汽间接加热方法干化污泥,污泥处理的直接成本最低,是最佳的污泥焚烧发电技术.     

北京市污泥处置现状及生态利用研究

针对北京市污泥处理处置现状及存在的主要问题,介绍了北京市污泥最终处置的发展规划,即热干化/焚烧、堆肥/农用及石灰干化/建材利用等三种模式,研究了污泥制生物炭土用于土地修复的可行性,并提出相应的保障对策,可为污泥的处置及利用提供一定的参考。     

Acid solubilization of sewage sludge and ash constituents for possible recovery

Many of the trace elements and phosphorus in digested sewage sludges can be solubilized with acid at an average acid cost of $41 and $77 per ton of dry solids for H₂SO₄ and HCl, respectively ($46 and $86/metric ton). But an economic gain accrued by the recovery of metals and phosphates would be minimal since processing of the large volumes of dilute acid leachate would be expensive. Based on acid costs alone, sludge detoxification does not seem to be economically feasible, so the elimination of metal discharges at source seems to be the only practicable solution to reducing heavy metal levels in digested sludges.

Sulfuric acid can be used to non-selectively solubilize metals and phosphates from sludge incinerator ash for about $21 per ton of ash treated ($24/metric ton). In most instances, separation and recovery of the constituents in the leachate would be too costly to make profitable recycle possible. Optimization of incineration parameters such as temperature can be used to minimize the environmental impact of landfilling sludge incinerator ash.     

污水处理厂污泥资源化利用技术分析

生活及工业中产生的污水量不断增加,污水处理厂处理后产生的污泥量也随之增大。目前,我国污泥的主要主要处理方法为填埋和焚烧。本文介绍了污水处理厂污泥组成、传统污泥处理方法、污泥资源化处理方法,并对污泥资源化处理案例进行分析,发现未来的污泥处理应侧重于资源回收、减少影响环境及节约经济成本等方向。     

INCINERATION ‐ IS THERE A CASE?

Incineration has suffered from a sustained campaign of misinformation. Consequently it has been regarded as the least sustainable option for the treatment of wastes, including sewage sludge. By looking carefully at the issues surrounding the incineration of sewage sludge, as an example, it can be seen that reality does not support the commonly held view. Modern plants are an effective means of recovering the energy value of sludge and at the same time offer a continuous operation, which is independent of weather or land constraints.
Of course incineration needs to be regulated and EU Directives and National Regulations set the emission standards. The technology is such that these standards can be met, and more than this, the systems are capable of upgrading as more stringent standards are imposed.
Concerns over NO_x, dioxins, metals and pathogens are highlighted. In addition the permitting process is discussed. None of these should present a barrier to the implementation of incineration projects. Indeed the paper goes further and demonstrates that there is likely to be an increasing role for incineration as landfill, recycling to agricultural land and other options become more restrictive.     

太原循环经济环卫产业园固体废物污水处理厂工艺设计

为解决太原循环经济环卫产业园内生活垃圾焚烧处理处置、餐厨垃圾处理处置及其他固废处理处置过程中产生的高浓度废水处理问题,拟新建一座污水处理厂。设计处理规模为1 200 t/d,主要包括750 t/d的焚烧厂垃圾渗滤液和450 t/d的餐厨沼液。渗滤液处理采用"气浮+调节池+内循环厌氧反应器+两级A/O-MBR"的核心工艺,餐厨沼液处理采用"气浮+调节池+两级A/O-MBR"的核心工艺。污泥处理采用"离心脱水+热干化"工艺,处理后污泥含水率≤30%,干化污泥采用密封车辆送至焚烧厂焚烧处理。试运行结果表明,出水水质稳定达到设计标准。污水处理厂总投资为1.3亿元,污水处理直接成本为23.5元/t。     

Physical and mechanical properties of municipal solid waste incineration residues with cement and coal fly ash using X-ray Computed Tomography scanners

A significant volume of Municipal Solid Waste incineration bottom ash and fly ash (i.e., incineration residues) are commonly disposed as landfill. Meanwhile, reclamation of landfill sites to create a new land space after their closure becomes an important goal in the current fewer and fewer land availability scenario in many narrow countries. The objective of this study is to reclaim incineration residue materials in the landfill site by using cement and coal fly ash as stabilizers aiming at performing quality check as new developed materials before future construction. Indeed, physical and mechanical properties of these new materials should be initially examined at the micro scale, which is the primary fundamental for construction at larger scale. This research examines quantitative influences of using the combination of cement and coal fly ash at different ratio on the internal structure and ability of strength enhancement of incineration residues when suffering from loading. Couple of industrial and micro-focus X-ray computed tomography (CT) scanners combined with an image analysis technique were utilized to characterize and visualize the behavior and internal structure of the incineration residues-cement-coal fly ash mixture under the series of unconfined compression test and curing period effect. Nine types of cement solidified incineration residues in term of different curing period (i.e., 7, 14, 28 days) and coal fly ash addition content (i.e., 0%, 9%, 18%) were scanned before and after unconfined compression tests. It was shown that incineration residues solidified by cement and coal fly ash showed an increase in compression strength and deformation modulus with curing time and coal fly ash content. Three-dimension computed tomography images observation and analysis confirmed that solidified incineration residues including incineration bottom and fly ash as well as cement and coal fly ash have the deliquescent materials. Then, it was studied that stabilized parts play a more important role than spatial void distribution in increment or reduction of compression strength.     

Phosphorus recovery from sewage sludge with a hybrid process of low pressure wet oxidation and nanofiltration

Phosphorus recovery from sewage sludge will become increasingly important within the next decades due to depletion of mineral phosphorus resources. In this work a new process concept was investigated, which aims at realising phosphorus recovery in a synergistic way with the overall sewage sludge treatment scheme. This process combines a low pressure wet oxidation for sewage sludge decomposition as well as phosphorus dissolution and a nanofiltration process to separate phosphorus from heavy metals and obtain a clean diluted phosphoric acid, from which phosphorus can be recovered as clean fertiliser.It was shown that this process concept is feasible for sewage sludge for wastewater treatment plants that apply enhanced biological removal or precipitation with alumina salts for phosphorus removal. The critical parameter for phosphorus dissolution in the low pressure wet oxidation process is the iron concentration, while in the nanofiltration multi-valent cations play a predominant role.In total, a phosphorus recovery of 54% was obtained for an exemplary wastewater treatment plant. Costs of the entire process are in the same range as conventional sewage sludge disposal, with the benefit being phosphorus recovery and reduced emission of greenhouse gases due to avoidance of sludge incineration.     

利用垃圾焚烧炉内循环处理垃圾焚烧飞灰的技术研究

将垃圾焚烧厂的垃圾焚烧飞灰作为球核主料和含碳还原剂以及必要的吸氯剂和催化剂制成复合球团,投入到垃圾焚烧炉进行高温还原分解二噁英,重金属形成玻璃态熔渣。从而对垃圾焚烧飞灰进行无害化处理,实现了垃圾焚烧飞灰在焚烧炉自身完整的闭路内循环处置,为处理垃圾焚烧飞灰提供了最佳技术路线。     

不同污泥处置方法中重金属的迁移规律

污泥中含有的重金属是污泥处置及其资源化利用中的主要限制因素，从污泥的土地利用、焚烧及制作建材三方面，论述了污泥中重金属的迁移规律及其影响因素，评价了上述3种污泥处置方法的安全性，提出了污泥资源化利用中需注意的问题。     

生活垃圾焚烧发电飞灰处置方法

随着我国城镇化进程的加快,生活垃圾产生量也在增加,原有的垃圾填埋导致土地资源越来越紧缺,作为生活垃圾处理的另一主要途径——焚烧发电技术得到了较大的发展。该技术不仅能变废为宝,将生活垃圾转变为电能和热能,更能促进生活垃圾减量化,有效解决了“垃圾围城”现象,缓解了土地资源压力。但焚烧过程中会产生含有二噁英、重金属等有害物质的飞灰,若飞灰处置不当则会对周边环境造成危害。     

固化疏浚淤泥作路基材料工程特性试验研究

为了探讨粉煤灰和工业矿粉固化疏浚淤泥作路基材料的可行性,通过一系列室内实验研究了不同固化剂配比对固化淤泥击实特性、水稳定性、承载力和抗剪强度的影响。实验结果表明,不同固化剂配比下固化淤泥的最大干密度均超过1.50g/cm3,最优含水率约为20~21%;淤泥固化处理后浸水4d的膨胀率均不超过1.1%,水稳性大幅提升;矿粉含量越高,粉煤灰含量越低,CBR(California Bearing Ratio)值越高,土样的承载力越高,抗剪强度也越高。不同工况浸水4d的CBR值均达到了较高的水平,工况SD10FA20MP(淤泥∶粉煤灰∶矿粉=7∶1∶2)CBR值最高,达到了34.8%,是规范中高速、一级公路路基填料要求最低CBR值的4.35倍,作路基填料使用可行。     

重庆城市污水处理厂污泥处理处置方案选择

三峡库区重庆段污水处理厂产生的污泥由于工艺、管理、机制问题等原因,还没有得到较好的处置。就当前面临的主要问题分析了三峡库区污泥处理处置的必要性,并结合三峡库区自然及社会经济条件等实际情况,提出了污泥处理处置的合理方案。该方案在解决三峡库区污泥出路问题的同时兼顾了环境效益、经济效益、社会效益的统一。