共查询到17条相似文献,搜索用时 114 毫秒
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为考察超声波-缺氧/好氧消化对污泥降解的效果,通过实验室中试对比试验,研究了污泥超声波-缺氧/好氧消化对传统好氧消化的比较优势。研究结果表明,经过25 d的消化后,超声波-缺氧/好氧消化污泥TSS和VSS的去除率分别达到了35.77%和50.02%,比好氧消化污泥分别提高了3.90%和8.99%;超声波-缺氧/好氧消化污泥稳定时间比好氧消化污泥缩短了近6 d;超声波-缺氧/好氧消化污泥的TN去除率为40.8%,远高于传统好氧消化,并且超声波-缺氧/好氧消化污泥上清液中氨氮和硝态氮浓度却远低于传统好氧消化,因而降低了上清液回流氨氮和硝态氮对污水处理系统的负荷压力。 相似文献
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为明确超声波促进污泥缺氧/好氧消化的减量化机理,采用设计的超声处理器联合缺氧/好氧消化反应器对污泥进行超声波-缺氧/好氧消化,研究了消化过程中SS、VSS的变化趋势,同时以未经超声处理的消化污泥作为对照。结果显示,消化污泥的SS、VSS在10天的消化过程中浓度逐渐减少,去除率逐渐增大,经过10 d的消化,超声污泥的SS和VSS浓度从10.64 g.L-1和5.59 g.L-1分别减少到7.53 g.L-1和3.23 g.L-1,而对照的VSS浓度从5.47 g.L-1减少为4.37 g.L-1,超声污泥的SS,VSS的去除率分别为29.16%和42.15%,而此时对照的VSS的去除率为20.20%,超声污泥和对照VSS去除率之差高达21.95%,超声波处理对污泥生物消化效率有明显的促进作用。 相似文献
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超声波对污泥脱水及厌氧消化影响的研究进展 总被引:1,自引:0,他引:1
超声波技术作为污泥厌氧消化预处理手段被广泛关注.超声波能改变污泥的性质,改善污泥厌氧消化的性能,但是其处理效果受到频率、强度、作用时间和发生方式等因素的影响,只有在合适的条件下,预处理效果才能达到最佳.本文着重介绍了超声波的频率、强度、作用时间和发生方式对污泥脱水性能、污泥沉降性能、微生物活性和污泥产气等多方面的影响.由于脱水性能和厌氧消化的改善所需要超声波的条件不一样,所以有必要通过进一步实验使预处理效果最优化;同时,为了进一步降低能耗,有效利用超声波与其它预处理技术相结合将是未来的研究方向. 相似文献
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浅议城市污水处理厂污泥处理技术路线 总被引:2,自引:2,他引:0
通过分析我国城市污水处理厂产生的不同类型污泥的特性,介绍了污泥"减量化"、"无害化"和"资源化"的技术措施及三者之间的关系,重点对减量化的工艺予以综述,提出了不同的减量化理念。在污泥资源化利用方面,通过详细介绍3个典型的污泥处理案例,将厌氧消化产沼气工艺、高温热水解-厌氧消化联合工艺和建材化水泥窑煅烧工艺进行了对比,阐述了不同工艺具有的优缺点。 相似文献
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目前,厌氧消化处是污泥减量化、无害化、资源化处理最有效的手段之一,沼气作为厌氧消化资源化产物,产量和纯度的原位提升技术有着重要的作用。文章从厌氧消化产沼气量影响因素和沼气原位富集技术的角度阐述沼气产量和纯度的提高的研究方法,从而对中国市政污泥处理和沼气能源化利用领域提供有价值的参考。 相似文献
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从现阶段国内外污泥处理与处置在环境和经济方面存在的问题出发,阐明了研究污泥减量化技术的紧迫性。重点介绍了代谢解偶联、溶胞-隐性生长、生物捕食等原位污泥减量化技术,以及焚烧、厌氧消化等后置污泥减量化技术的原理和特点,并指出了这几种技术的研究发展方向和应用前景。 相似文献
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超声波促进处理剩余活性污泥中试研究 总被引:3,自引:1,他引:2
文章进行了超声波促进污泥脱水减量并提高污泥厌氧消化效率的中试。中试装置每天可处理3 000 kg含水质量分数在99%以上的剩余活性污泥。实验结果表明,当超声波频率为28.7 kHz、输出电压为70 V,作用时间为2 m in,絮凝剂投加质量分数为8‰(干基)时,污泥滤饼含水质量分数比未经超声波作用的降低2%,体积减少8%,污泥的脱水效果最佳。当超声波输出电压为150 V,作用时间60 m in时,污泥厌氧消化时间比传统方法缩短20 d。同时沼气产生速率比未经超声波作用的提高6倍,前25 d沼气总产量比传统污泥厌氧消化过程增加4—5倍。可见大功率、长时间有利于促进厌氧消化,从而达到污泥减量的目的。 相似文献
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Ultrasonic treatment and thermal treatment at low temperature were employed together to analyze and compare the effect of
temperature on ultrasonic sludge hydrolysis. Waste activated sludge was more susceptible to ultrasound than anaerobic sludge
and primary sludge. In ultrasonic treatment of waste activated sludge for 1 hour, ΔSCOD/(−ΔVSS) ratio decreased from 2.40
to 0.44, indicating that high COD components were solubilized faster than the low COD components. Ultrasonic treatment increased
the temperature significantly and the heat effect on sludge hydrolysis was not negligible. Primary sludge was more susceptible
to heat than waste activated sludge. A sequential treatment of heat and ultrasound of primary sludge showed that hydrolysis
efficiency was more affected by the ultrasonic power than the temperature and the time duration. In case of waste activated
sludge, the overall hydrolysis efficiency increased with the temperature up to 50°C, and it remained almost constant at higher
temperature. From the results the contribution of shear force by cavitation bubbles decreased at higher temperature. The effects
of shear and heat in ultrasonic sludge treatment need to be analyzed separately for the optimum sludge pretreatment. 相似文献
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由于在超声波声场中污泥微粒会发生分层现象,声互作用力使得微粒于超声传播方向相垂直的平面上发生凝聚,因此污泥厚度大小对超声波辅助热风干燥污泥特性有着重要的影响。通过实验的方法,对不同厚度污泥在超声波声场中的分层凝聚现象进行观察,发现污泥内部结构的分层现象随其厚度的增加而明显。研究了超声波对不同厚度污泥干燥过程中各时期干燥时长、干燥速率的影响效果,以及分析了湿分有效扩散系数(Deff)随污泥厚度变化的情况。从实验结果中可以发现,在超声波功率小于135 W范围内,污泥厚度越大,干燥过程中第一降速期时间越长,干燥速率提升效果越差,而对恒速干燥期内干燥速率提升效果更明显;在5、10以及15 mm厚度的污泥中,10 mm厚度的污泥在超声波功率小于90 W的条件下总干燥时长降低幅度最大,干燥速率在各阶段提速也较快;污泥厚度越小,超声波功率对污泥湿分有效扩散系数影响越小,反之影响越大。 相似文献
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Effect of sludge thickness on characteristics of ultrasonic assisted hot air drying sludge
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Due to the stratification of sludge particles in the ultrasonic field, the acoustic interaction forces the particles to agglomerate on a plane perpendicular to the direction of ultrasonic propagation. Therefore, the thickness of sludge can significantly influence the characteristics of ultrasound-assisted hot air convective drying municipal sewage sludge. In this paper, the stratified aggregation phenomenon of sludge with different thicknesses was observed in the ultrasonic field using the experimental method. It was found that the stratification of the internal structure of sludge became more obvious with the increase of its thickness. The effects of ultrasound on the drying time and the drying rate of sludge with various thicknesses were studied. Meanwhile, the effective moisture diffusivity (Deff) was analyzed. The experimental results demonstrated that the larger the sludge thickness, the longer the time length of the first falling rate stage and the promotion of the drying rate was worse when the ultrasonic power was less than 135 W. The situation was opposite at the constant rate stage. Among the sludge with the thicknesses of 5, 10, and 15 mm, the total drying time and energy consumption of the sludge with a thickness of 10 mm decreased the most substantially under the condition of ultrasonic power less than 90 W. The smaller the thickness of sludge is, the less obvious the effect of ultrasound on the effective moisture diffusivity, and vice versa. 相似文献
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目前,超声波是一种在工业中广泛应用的技术,可以用于油田管道的污垢清理。为了更加深入研究超声波除碳酸钙垢的效果,有必要探究超声波的参数对除垢率的影响。在实验室条件下,组装了一套超声波除垢设备,通过改变超声波的频率、辐照时间和辐照温度,分别处理Q235钢制挂片上的碳酸钙垢,采用处理前和处理后挂片质量差的方法来评价除垢效果。实验结果表明在频率为28 kHz、辐照时间为10 min和辐照温度为40℃的条件下,超声波除碳酸钙垢能力强、效果好。因此,优选出超声波不同参数之间的组合对提高除碳酸钙垢率至关重要。 相似文献
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Shen Jinfeng Yin Xuan Gu Heping Lü Xiaoping 《Frontiers of Chemical Engineering in China》2007,1(4):395-398
To investigate the influence of ultrasound pretreatment on sludge anaerobic digestion, the ultrasound disintegration of residual
sludge in water treatment of petrochemical plant was studied, and the mechanisms of ultrasound and medium were introduced.
Experimental results indicate that ultrasound cavitation induces the rise of sludge temperature, which improves ultrasound
disintegration on sludge. Ultrasound pretreatment can advance observably the quantity of chemical oxygen demand in sludge
supernatant fluid (SCOD), which increases with ultrasound intensity and sonication time. The degree of ultrasound disintegration
increases with the specific energy input. When the specific energy input is 10 000 kJ/kg of total dry solids, the degree of
ultrasonic sludge disintegration reaches 40%.
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Translated from Chemical Engineering, 2006, 34(11): 64–67 [译自: 化学工程] 相似文献