造纸污泥太阳能干化处理工艺设计

太阳能作为一种清洁能源,将其应用在造纸污泥干化中,与传统干化工艺相比具有能耗低、无污染、运行费用低廉、操作简单、运行安全稳定、干化后的污泥仍保留原有的价值等特点。以某造纸污泥的干化为例,介绍了该工艺的工作原理及流程、工艺单元设计等。     

宝钢股份有限公司三烧结脱硫技术

宝钢股份有限公司三烧结脱硫采用气喷旋冲脱硫技术,主要介绍了宝钢三烧结脱硫系统工作原理,技术特点,以及运行时的关键参数等。     

Possible solutions for sludge dewatering in China

In China, over 1.43×10⁷ tons of dewatered sewage sludge, with 80% water content, were generated from wastewater treatment plants in 2007. About 60% of the COD removed during the wastewater treatment process becomes concentrated as sludge. Traditional disposal methods used by municipal solid waste treatment facilities, such as landfills, composting, or incineration, are unsuitable for sludge disposal because of its high water content. Disposal of sludge has therefore become a major focus of current environmental protection policies. The present status of sludge treatment and disposal methodology is introduced in this paper. Decreasing the energy consumption of sludge dewatering from 80% to 50% has been a key issue for safe and economic sludge disposal. In an analysis of sludge water distribution, thermal drying and hydrothermal conditioning processes are compared. Although thermal drying could result in an almost dry sludge, the energy consumption needed for this process is extremely high. In comparison, hydrothermal technology could achieve dewatered sewage sludge with a 50%–60% water content, which is suitable for composting, incineration, or landfill. The energy consumption of hydrothermal technology is lower than that required for thermal drying.     

冷冻对脱水污泥干燥与燃烧特性的影响

为了研究冷冻对脱水污泥干燥与燃烧特性的影响,考察了不同冷冻温度对污泥干燥效果的影响.利用同步热重分析仪(TG-DTA)研究了不同冷冻温度和升温速率对脱水污泥燃烧特性的影响,并进行了污泥燃烧动力学分析.结果表明:与原泥相比,冷冻将脱水污泥变成了可进行破碎的硬质结构,当温度降到-20℃时,破碎污泥的干燥速率提升了41.46...     

Sedimentary Causes and Management of Two Principal Environmental Problems in the Lower Yellow River

Flood and water shortage are two of the leading environmental problems around the world, and among the causes of the problems is sedimentation. The Yellow River brought disastrous floods in its lower reaches in Chinese history. Today, although floods caused by the river are still a formidable hazard hanging over China, it cannot provide the lower reaches with enough usable water. The ineradicable flood hazard and newly emerged water shortage problems of the river are proved to be closely associated with its immense sediment load. The over loaded flow of the river can quickly fill the reservoirs and unceasingly raise the riverbed, attenuating the capacity of reservoirs to suppress floods and provide more water for dry seasons and of river channels to convey floods. Also, the high sediment content pollutes the water and reduces the volume of usable water. In virtue of the intimate linkage between these problems and the formidable sediment load in the river, the solution to these problems should be based on sedimentation management. After reviewing the defects and merits of management measures implemented and proposed, a management scenario composed of multiple measures are recommended. Beside of persistent soil conservation to reduce the huge sediment load, more reservoirs to check sediment and regulate river flows, approaches to alleviating riverbed accretion, interbasin water transfer to mitigate water deficiency, and so on, an emphasis should be laid on use of muddy flows in order to scatter the sediment in a vast area, which was a natural process but has been interrupted by construction of embankments.     

流化填料在城市污水厂污泥减量中的试验

采用投加流化填料的方法对传统的城市污水处理厂工艺进行改造，可降低剩余污泥的产量，减少污水处理厂在污泥处理上的费用，并且在改造中不需要土建投资，不需要停水停产。本试验对老城市污水处理厂的挖潜、节能、升级改造具有实际意义。     

坑口电站锅炉磨损特性研究

坑口电站可以直接将一次能源转化为二次能源,减少输煤损失和环境污染,具有很大的优势.根据矿区多产煤矸石的特点,循环流化床锅炉得到了广泛的应用,它有煤种适应性强、效率高等许多优点,但各受热面磨损较快,影响安全运行.本文从设计、运行等方面研究循环流化床锅炉的受热面磨损特性问题,并以龙煤集团某1×135 MW机组锅炉磨损为研究对象,通过对床料特性、运行参数、受热面结构布置、燃料特性等方面的影响分析,在防磨材料、结构设计、施工、运行等方面,给出了安全对策措施,从而可以保证坑口电站循环流化床锅炉的长期安全稳定运行.     

干湿交替条件下不同晶型铁氧化物对水稻土甲烷排放的影响

以典型华南水稻土为研究对象,通过室内恒温培养试验,分析了不同水分条件下[干湿交替(DW)和持续淹水(CF)]不同晶型铁氧化物[水铁矿(SF)和赤铁矿(SH)]对水稻土CH4平均排放速率及产CH4潜力的影响.结果表明,与CF相比,DW处理的CH4平均排放速率平均减少了61%以上;与没有添加铁氧化物的处理相比,铁氧化物抑制了53%的CH4排放.DW与铁氧化物的耦合抑制了65%~94%的产CH4平均排放速率及57%~93%的产CH4潜力,抑制效果明显高于DW或铁氧化物的单独作用.其中DW耦合晶型较弱的水铁矿(SF-DW)所产生的抑制效应(94%)明显高于DW耦合晶型较好的赤铁矿(SH-DW,65%).统计分析结果表明Fe(Ⅲ)浓度与水稻土CH4排放速率存在显著负相关性(R2=-0.98,P<0.01).且实验结果表明,DW可以加速Fe(Ⅲ)的循环再生,而晶型较弱的SF易还原性使其Fe(Ⅲ)的循环再生更易受到DW的影响.上述结果说明,DW可以促进铁氧化物对水稻土CH4排放及产CH4潜力的抑制效应,且干湿交替与晶型较弱的水铁矿的耦合效应比干湿交替与晶型较高的赤铁矿的耦合效应更为显著.     

脱水污泥热干化和微波干化过程及机理比较分析

以脱水污泥为原料,分别采用恒温热干化和微波干化2种不同的方法考察脱水污泥的干化情况;对不同干化阶段的污泥进行显微观察,分析干化过程;并对2种干化过程的机理进行了探讨。实验结果表明随着加热温度的升高,污泥中水分脱除速度加快。加热温度低于100℃时,在120 min以内,热干化无法达到较高的脱水率。加热温度在140℃以上,加热时间120 min时,脱水污泥的脱水率可达到98.26%。微波干化法在功率为500~900 W,5~10 min内可使脱水污泥的脱水率到达99.20%以上。机理分析表明热干化传质与传热方向相反,微传热和传质的方向相同,因此微波干化具有更快速、高效的特点。     

流化床污泥干化系统密封工艺的国产化改进研究

文章介绍了流化床污泥焚烧干化工艺,提出了系统中氧含量控制的重要性和必要性,并阐述了在实际操作过程中问题出现的原因。针对进口设备国产化出现的系统密封问题,对污泥干化系统的影响,以及系统密封工艺的改进,与之相关的工艺操作和工艺参数的调整提出了有针对性的改进措施。通过对系统工艺的改进和系统相关工艺参数的调整,污泥干化系统的操作达到了较好的效果,使得系统氧含量的控制达到了4%以下,优于系统设计要求8%。对污泥无害化处理设备国产化进行了积极的探索和实践。