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1.
常治铁 《中国冶金》2019,29(10):65-70
焦炉烟气中存在的大量SO2和NOx是形成酸雨和雾霾的主要污染物。为了落实当前环保生产的基本国策,对焦炉烟气进行脱硫脱硝除尘处理已成为各大企业的当务之急。主要研究了SDS干法脱硫+中低温SCR脱硝除尘工艺在实际工程中的应用,该工艺效率高,副产品少,抗冲击能力强,是目前国际上一种较为先进的焦炉烟气净化处理技术。采用SDS+SCR工艺对鞍钢股份有限公司炼焦总厂8号焦炉烟气进行脱硫脱硝处理,实际结果表明,当设备入口处焦炉烟气中SO2、NOx和粉尘的平均质量浓度分别为83.84、439.67和18.43 mg/m3时,出口处烟气中3种污染物的质量浓度分别低于30、150和5 mg/m3,满足GB 16171-2012中的排放要求。研究可以为焦化行业的污染物治理提供可鉴方案和经验。  相似文献   

2.
本文通过对烧结烟气脱硫脱硝技术用于高硫烟气(SO2质量浓度高)条件实现超低排放的可行性进行分析,筛选出用于高硫烧结烟气脱硫脱硝超低排放技术:石灰石-石膏脱硫+SCR脱硝。结合高硫烧结烟气特点,提出了一种适合的技术路线:电除尘+石灰石-石膏脱硫+非湿电式深度净化+一级烟气补热+GGH+二级烟气补热+中温SCR脱硝。基于该技术路线的超低排放工艺在高硫烧结烟气治理上进行了应用,处理后烟气中颗粒物、SO2、NOx的质量浓度分别为7.01、8.25、35.31 mg/Nm3,能够连续稳定实现超低排放。  相似文献   

3.
文章介绍了八钢四座6.5m顶装焦炉烟气治理工艺采用的活性焦联合脱硫脱硝工艺,以及脱硝段采用CSCR(活性炭选择催化还原)技术。该烟气治理工艺投运后,烟气排放指标SO_2≤30mg/m~3,NO_X≤150mg/m~3。  相似文献   

4.
介绍了焦炉烟气半干法脱硫+SCR脱硝工艺流程,并分析了存在的问题。通过优化脱硫剂制备及喷浆技术、补热技术、建立新型焦炉加热制度;改造脱硫剂制备管道连接方式,对脱硝除尘一体化装置密封改造,增加设备工艺安全联锁功能,提高进入脱硝工序烟气温度等措施,保证了焦炉烟气脱硝工艺运行稳定,实现了焦炉烟气粉尘、NO_x、SO_2达标排放,主要物料消耗明显降低。为同行业污染物排放控制提供了参考。  相似文献   

5.
焦化行业污染物排放量较大,国家对烟气排放要求日趋严格。本文分析了焦炉煤气的特点,对比目前国内主要的脱硫、脱硝技术及其优缺点,并分析了焦化行业常见的5种脱硫脱硝组合工艺特点和适用情况。焦化企业选取烟气净化工艺路线时,应充分考虑焦炉烟气的温度、污染物的浓度、焦炉工艺、资源情况以及副产物处理要求等因素,选择可靠、先进、成熟的脱硫脱硝技术,在出口指标达标的前提下,最大限度地利用烟气温度梯度,减少能源消耗。  相似文献   

6.
以梅钢7×105 m3/h烧结机烟气的脱硫脱硝为背景,研究了实际工程应用中臭氧对烟气的氧化和半干法对氧化产物(NOx和SO2)的吸收等问题。结果表明,臭氧喷入点位置对烟道内NOx氧化影响不大,喷射格栅保证了臭氧和烟气的均匀混合。吸收塔出口烟气温度对脱硝影响显著,NOx的吸收效率会随着温度的升高而降低,当温度高于95 ℃时,脱硝效率为0;而脱硫塔出口烟气温度变化对SO2吸收几乎没有影响。优化后的烧结烟气脱硫脱硝系统连续运行数据表明,出口SO2质量浓度均值为16.83 mg/m3,出口NOx质量浓度均值为72.33 mg/m3,均达到了系统设计要求。系统运行成本为10~11元/t,与活性炭烟气净化技术、循环流化床+SCR工艺技术相比,臭氧氧化 半干法吸收协同脱硫脱硝工艺具有明显的优势。  相似文献   

7.
开发了冶金烟气除尘与催化脱硫脱硝一体化集成技术。利用SEM测试了陶瓷管的微观结构,并考察造孔剂含量对陶瓷复合膜性能的影响。结果表明,陶瓷内层是粒径较大的支撑膜,表层是粒径较小的分离膜,有规则形状的微观孔隙,有利于粉尘和烟气的过滤。随着造孔剂含量的增加,显气孔率明显增加,而体积密度和抗压强度减小。陶瓷复合膜在600 ℃具有较好的抗热震性及耐酸碱性能。针对某焦化厂烟气采用无氨低温催化脱硫脱硝技术,使SO2排放浓度从基准期的200~300 mg/m3(标态)降至0.2~0.5 mg/m3,脱硫率达99%以上,NOx排放浓度由800~1 200 mg/m3降至80~180 mg/m3,脱硝率达50%~88%。  相似文献   

8.
介绍了焦炉烟道气中SO2和NOx的形成机理,以及同时脱除的技术难点.对照国家最新的行业排放标准要求,鉴于世界上尚无长期稳定运行的工程案例,对比了两种已在境外烧结行业大型工业化工程中实现长期稳定运行的烟气脱硫脱硝技术,提出了可在大型焦炉烟道气脱硫脱硝中采用的工艺技术路线——半干法烟气脱硫(SDA/CFB)+选择性催化还原(SCR)组合式脱硫脱硝技术.分类阐述了不同温度的焦炉烟道气脱硫脱硝工艺技术路线,展望了焦炉烟道气脱硫脱硝项目的发展前景.  相似文献   

9.
为达到《关于推进实施钢铁行业超低排放的意见》(环大气[2019]35号)钢铁企业超低排放标准,西王金属科技有限公司在原湿式电除尘、石灰—石膏湿法脱硫、低温氧化法脱硝的基础上,实施了一系列技术改造。通过采用加热SCR脱硝、双塔双循环石灰—石膏法脱硫、高压脉冲电源双室四电场+湿式电除尘去除颗粒物、两降一升烟气消白工艺技术,在基准氧含量为16%时,达到了出口烧结烟气中氮氧化物浓度≤50 mg/m3、二氧化硫浓度≤35 mg/m3、烟尘浓度≤10 mg/m3,实现了烧结过程超低排放。  相似文献   

10.
为了实现烧结烟气的深度治理,基于逆流式活性炭脱硫脱硝工艺,宁钢建设了一套采用模块化设计、脱硫脱硝分层、活性炭循环利用等先进技术的脱硫脱硝系统。系统平稳运行后,净化烟气中二氧化硫、氮氧化物、颗粒物排放指标分别为5mg/m3、46mg/m3、8mg/m3,实现了烧结烟气的超低排放。同时,对该系统运行过程中存在的问题给出了解决措施,为该技术的广泛应用提供了参考。  相似文献   

11.
Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.  相似文献   

13.
鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".  相似文献   

14.
张兴强  叶运福 《冶金设备》2005,(6):71-72,47
针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。  相似文献   

15.
转炉炉壳热应力分析   总被引:5,自引:1,他引:4  
任学平  郭志强  邹家祥 《炼钢》2001,17(6):47-49
根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。  相似文献   

16.
In this paper is treated the fundamental problematic of the fracture of the diaphysis of the tibia and the therapeutic results after the conservative and operative treatment are confronted. Among 518 patients with 433 open fractures and 35 with closed fractures of the diaphysis of the tibia, successful treatment of more 2/3 was obtained in the period from 1968 to 1972. Following our casuistics and literature, whose results are similar, we find out that the average total treatment of the osteosynthesis of the fracture of the diaphysis was shortened for 2,5 months depending upon the type and the localisation of the fracture. Apolied methods of the operative and conservative and conservative treatment in relation to the velocity of the medical cure as well as to the extreme anatomical-functional results are analised. We noticed that osteosynthesis, made by the intermedullary nail and the extension of the canals or by a small AO table, by the achieved stability makes conditions of immediate motions and an early rehabilitation. Because of that it gives the best functional results.  相似文献   

17.
18.
Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.  相似文献   

19.
通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。  相似文献   

20.
为了编制实用性强的基地建设行动方案,首先,确定参与式发展的主体,搭建一个"决策框架";其次,针对行动目标,提出不同参与主体,如管理者、农民、消费者等团队与个人的目标及行动内容;最后,工作应向重塑伙伴式合作关系,挖掘农民自我发展潜力,完成三大角色的转换,打造农业基地文化等方向推进.  相似文献   

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