共查询到19条相似文献,搜索用时 156 毫秒
1.
2.
超临界水氧化技术及其应用 总被引:1,自引:0,他引:1
超临界水氧化技术(SCWO)是一种新型的有机废水处理技术,具有反应速率快、处理效果好、不形成二次污染和去除效率高等优点。介绍了超临界水的特性和氧化反应机理,综述了SCWO在处理火炸药生产废水中的应用,并针对其存在的设备腐蚀、反应器堵塞等问题提出了解决方法和研究方向。 相似文献
3.
综述了超临界水氧化技术在废水处理中应用的国内外背景,主要介绍了目前国内超临界水氧化技术废水处理的研究和应用情况。阐述了超临界水氧化技术的原理,和统的废水处理方法相比,超临界水氧化技术废水处理有反应快、彻底、污染小、容易分离、高效节能等优点,也存在易腐蚀、易堵塞、一次投资高等问题。 相似文献
4.
超临界水及其氧化反应的研究及应用 总被引:3,自引:0,他引:3
超临界水(SCW)具有与常态下的水截然不同的性质,由此导致了超临界水的多种用处。超临界水氧化(SCWO)作为一种以超临界水为介质的新的废物处理技术以其完全快速等优点而日渐成为研究的热点。本文介绍了超临界水的特性和超临界水氧化的基本原理,反应器的装置,综述了超临界水氧化的动力学、应用、工艺改进、工程问题等方面的研究进展情况。 相似文献
5.
6.
7.
8.
9.
10.
11.
Dong H. Xu Shu Z. WangYan M. Gong Y. GuoXing Y. Tang Hong H. Ma 《Chemical Engineering Research and Design》2010
Reactor plugging and corrosion are the key problems which hinder commercial applications of supercritical water oxidation and gasification, and can be efficiently overcome by preventing salt deposition on internal surface of reactor. In this work the problems caused by salt deposition and the correspondingly main solutions are further reviewed objectively. A novel reactor is designed and manufactured with a feed rate of about 100 L/h for sewage sludge treatment. The reactor combines the characteristics of Modar reactor and transpiring wall reactor for the first time, which is expected to prevent reactor plugging and corrosion as well as to decrease catalyst deactivation rate. The reactor is the core equipment of the first pilot-scale plant for supercritical water oxidation in China. Further optimizations of reactor configuration and operational parameters need plenty of experiments and/or a long-time test with sewage sludge in the subsequent work. 相似文献
12.
Donghai Xu Peng Feng Yang Wang Wanpeng Yang Yu Wang Shaoyan Sun 《American Institute of Chemical Engineers》2022,68(2):e17472
Corrosion and salt deposition problems severely restrict the industrialization of supercritical water oxidation. Transpiring wall reactor can effectively weaken these two problems by a protective water film. In this work, methanol was selected as organic matter, and the influences of vital structural parameters on water film properties and organic matter removal were studied via numerical simulation. The results indicate that higher than 99% of methanol conversion could be obtained and hardly affected by transpiration water layer, transpiring wall porosity and inner diameter. Increasing layer and porosity reduced reactor center temperature, but inner diameter's influence was lower relatively. Water film temperature reduced but coverage rate raised as layer, porosity, and inner diameter increased. Notably, the whole reactor was in supercritical state and coverage rate was only approximately 85% in the case of one layer. Increasing reactor length affected slightly the volume of the upper supercritical zone but enlarged the subcritical zone. 相似文献
13.
14.
《The Journal of Supercritical Fluids》2009,48(3):382-390
This paper is a review of applications of near and supercritical water with a focus on supercritical water oxidation (SCWO). Hydrolytic and hydrothermal reactions have been reviewed in Part I [G. Brunner, Near critical and supercritical water. Part I. Hydrolytic and hydrothermal processes, J. Supercrit. Fluids, this issue]. The potential lies in the complete destruction of persistent, anthropogenic waste material. The obstacles in the technical application are due to the highly corrosive reaction medium and the precipitation of salts. Reactor construction is the decisive feature for a commercial process. First, tank type reactors had been favored. Corrosion was kept low by ceramic material and salt deposition was avoided by a stream of cold and clean water at the reactor vessel walls. Later, tubular reactor design was preferred, and several means to prevent corrosion and salt deposits have been applied. 相似文献
15.
Donghai Xu Shuzhong Wang Chuanbao HuangXingying Tang Yang Guo 《Chemical Engineering Research and Design》2014
Reactor corrosion and plugging problems have hindered the commercialization of supercritical water oxidation (SCWO) for wastewater purification. The use of transpiring wall reactor (TWR) is an effective means to overcome the above two problems by forming a protective water film on the internal surface of the reactor to aviod contacting corrosive species and precipitated organic salts. This work mainly aims to objectively review experimental investigations and numerical simulation results concerning TWR. Subsequent investigations for parameters optimizations of TWR are also proposed in order to ultimately build effective regulation methods of obtaining excellent water film properties. All this information is very important in guiding the structure design and operation parameters optimization of TWR. 相似文献
16.
超临界水氧化是水处理技术发展的新方向,但该技术对设备的要求比较高,工业化应用仍有一定的难度。为了克服这一难题,目前的研究工作主要集中在催化剂的选择以及设备防腐蚀等方面。介绍了贵金属类催化剂、过渡金属类催化剂、碱金属盐类催化剂、杂聚酸类催化剂以及碳基类催化剂,在降解不同污染物时的催化效率。在反应器材质和反应器形式的研究中,分别对铁、镊、铬等纯金属以及不同材料的合金在各种条件下的防腐蚀性能作了比较;两种最新的反应器形式:可蒸发壁式反应器和流动式反应器。它们在超临界水氧化中表现出了良好的防腐能力。 相似文献
17.
超临界水氧化技术的发展面临着腐蚀和盐沉积两大技术难题,采用蒸发壁反应器是解决这两大技术难题最为有效的方法。本文综述了国内外蒸发壁反应器的结构特点和性能,分析了基于蒸发壁反应器的超临界水氧化技术应用过程中仍然存在的问题,如多孔管的性能、物料的预热、系统能量利用及经济性,并提出了相应的解决办法。 相似文献
18.
19.
CFD simulation of a transpiring‐wall SCWO reactor: Formation and optimization of the water film 下载免费PDF全文
A two‐dimensional axisymmetric computational fluid dynamics model of a transpiring wall reactor for supercritical water oxidation was developed using the commercial software Fluent 6.3. Numerical model was validated by comparisons with experimental temperature profiles and product properties (total organic carbon and CO). Compared with the transpiration intensity, the transpiring water temperature was found to have a more significant influence on the reaction zone. An assumption that an ideal corrosion and salt deposition inhibitive water film can be formed when the temperature of the inner surface of the porous tube is less than 374°C was made. It was observed that lowering transpiring water temperature is conducive to the formation of the water film at the expense of feed degradation. The appropriate mass flux ratio between the total transpiring flow and the core flow was determined at 0.05 based on the formation of the water film and feed degradation. © 2015 American Institute of Chemical Engineers AIChE J, 62: 195–206, 2016 相似文献