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1.
总结了国内外烧结余热发电技术及烧结余热资源的特性,并据此建立了烧结余热发电系统热力学模型,分析了主蒸汽参数与余热发电系统最大发电能力的关系,以及影响系统发电功率的主要因素,得出了最佳的主蒸汽参数.  相似文献   

2.
采用双压饱和蒸汽发电系统,可解决烧结余热发电系统中热源不稳定的问题.本文以某厂520m2烧结机环冷余热发电系统为例,就双压饱和蒸汽发电系统的压力选择对其余热利用率和发电量的影响进行了分析,以期为烧结余热发电系统的优化设计提供理论依据.  相似文献   

3.
胡长庆  闫龙格  赵凯 《钢铁》2017,52(3):88-92
 针对烧结余热发电系统运行稳定性差及停机率较高的问题,基于概率理论建立了多台烧结余热锅炉并联运行发电系统数学模型,分析了余热锅炉工作状态对余热发电系统稳定运行的影响,提出了烧结余热锅炉与发电系统稳定运行方案和蒸汽量调控策略。现场数据表明,多台余热锅炉并联运行,发电机组运行稳定性改善;4台余热锅炉并联共用1台发电机组的烧结余热发电系统,3台及以上余热锅炉正常工作,即可保证系统稳定运行概率大于0.98;当系统蒸汽量不足时,通过管网调入蒸汽,发电系统稳定运行概率可达到0.96以上。  相似文献   

4.
徐忠 《冶金能源》2013,(1):33-37
烧结余热发电领域的新技术——直联炉罩式余热锅炉技术,首次成功应用于方大特钢科技股份有限公司烧结余热发电项目中,它运行良好,投资省,占地小,结构简单紧凑,能降低散热损失和阻力损失,提高余热锅炉产汽量和出口蒸汽温度,克服现有烧结余热发电技术的不足之处,大幅度提高烧结冷却机废气的热能利用率,节能效果和经济效果显著。  相似文献   

5.
李江 《四川冶金》2013,35(2):44-46
烧结冷却机余热发电技术是利用烧结冷却机中低温的废气通过余热锅炉产生蒸汽,来推动汽轮机组做功发电.本文对烧结冷却机纯低温余热发电热力工艺系统、热力参数等特点及发电能力进行了探讨、分析、比较,通过工程实例及结论,为合理选择余热发电技术及提高发电能力提供参考.  相似文献   

6.
针对钢铁企业烧结余热发电系统的热源不稳定性,统筹考虑余热锅炉产汽系统和发电系统,通过建立双压余热发电系统数学模型,以系统发电能力最大化为目标,实时得到两关联系统的中、低压蒸汽压力最优值,跟踪模型参数最优值并按其在线控制,使系统随外部条件变化自动保持最优运行。  相似文献   

7.
介绍了烧结余热发电的特点,通过分析烧结余热发电的关键技术,提出了保证系统稳定运行、提高余热回收效率的方法。  相似文献   

8.
提高烧结余热发电量的实践   总被引:1,自引:0,他引:1  
宋磊 《烧结球团》2008,33(2):55-58
马钢二铁烧结废气余热发电项目自2005年9月投入运行后,由于种种原因,余热发电生产极不稳定,发电量较低.为此,通过稳定烧结工艺操作,改进带冷密封提高烟气温度,以及优化余热发电系统等,大幅度提高了发电量.  相似文献   

9.
钢铁厂烧结余热发电是烧结余热利用的主要形式之一,利用余热发电盈利来降低吨钢能耗,积极响应了国家“十二五”规划要求节能减排的政策。然而,烧结余热有自身不稳定的特点,严重影响了发电机组稳定性、安全性及运行寿命。针对烧结余热发电不稳定性对机组产生的影响做了分析和总结,并介绍了市场常用的解决方案,并分析了各方案的优缺点。还着重分析了动态补燃系统优缺点,该系统有效解决了烧结余热发电的不稳定性。  相似文献   

10.
庞蕊霞 《甘肃冶金》2014,(4):132-134
余热发电是当前提高二次能源利用率,节约能源的一项有效措施。本文主要研究分析国内烧结余热发电的现状,针对酒钢本部烧结机余热利用情况,提出余热利用的改进建议,有效提高酒钢烧结二次能源的综合利用率,最大程度的节约能源、降低企业生产成本,提升企业竞争力。  相似文献   

11.
12.
Two studies investigated the role of expressive vocal behavior (specifically, speech rate and loudness) in fear and anxiety and in sadness and depression. In the 1st study, participants spoke about personally experienced fear and anxiety-arousing and neutral events using 3 different voice styles: fast and loud, normal, and slow and soft. In the 2nd study, participants spoke about personally experienced sad or depressing and neutral events using the same 3 voice styles. In both studies, the participants' highest levels of subjective affective and cardiovascular (CV) arousal occurred when they spoke about the emotional events in a mood-congruent voice style: fast and loud in the case of fear and anxiety, and slow and soft in the case of sadness or depression. Mood-incongruent voice styles canceled the heightened levels of CV arousal normally associated with these negative emotions. The voice-style manipulation had no significant effect on the participants' levels of CV arousal during the neutral discussions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
Despite the use of multimodal therapy, higher-grade glioma is still uniformly fatal in the adult population. There is a considerable difference between the length of survival in each given patient, even within the same tumor type and malignancy grade group, suggesting that there are factors that might differentially influence outcome. To identify such factors, 107 patients with anaplastic or malignant glioma were retrospectively investigated. Clinical parameters and paraclinical data on the p53, mdm2, and EGFR genes at the DNA or protein level were evaluated by univariate analysis and Cox proportional hazards regression modeling. Kaplan-Meier survival estimation demonstrated that immunohistochemical positivity for mdm2 protein in patients with anaplastic astrocytoma or with glioblastoma multiforme was associated with a shorter survival time (p = 0.02). P53 gene mutations and immunopositivity for the epidermal growth factor receptor (EGFR) protein were not significantly related to poor prognosis. The Cox proportional hazards model revealed immunohistochemical positivity for p53, mdm2, or for both of them, the presence of postoperative irradiation, and the extent of surgical resection of tumor to be variables significantly associated with prolonged survival. EGFR overexpression, age over 60 years, and Karnofsky performance score below 40 points did not significantly shorten survival time. In conclusion, the present study identified immunohistochemically detected mdm2-protein overexpression as a statistically significant negative prognostic parameter in patients bearing anaplastic or malignant glioma. Association analysis of variables revealed a possible correlation between mdm2 and p53, which is also consistent with the biological interaction mode of both proteins in vivo.  相似文献   

14.
BACKGROUND: As aging research increasingly reflects an effort to dissociate true time-driven changes from those that can be improved, sexuality in later life remains largely unexplored. Several problems are evident. There is a lack of normative data, a lack of a conceptual framework relating to the biology, psychology, and sociology of sex, and an attitudinal resistance that obscures the entire topic. METHODS: We conducted a three-part instructional series on major topics involved with sexuality and aging. We surveyed our group of attendees (n 158, average age 68 for males, 65 for females) before and after the series. RESULTS: A remarkably robust sex life was evidenced by both the men and the women, even until advanced old age. Yet, a substantially decreased involvement was reported from 10 years earlier. Despite current activities, people of both sexes wished they were participating even more than they currently were. Impotency was identified as the major negative feature for the men; relationship problems were for the women. A questionnaire 6 months after the series reported improved sexual attitudes, but no change in sexual activities from the earlier survey. CONCLUSION: Sexuality is a major quality-of-life issue which persists into old age. Our study showed that the usual sexual practices reported by our group were not considered by them to be ideal. The intervention of this instructional series provided improved sexual attitudes but not performance. Additional studies are encouraged.  相似文献   

15.
OBJECTIVE: To test the validity of Benjamin Franklin's maxim "early to bed and early to rise makes a man healthy, wealthy, and wise." DESIGN: Cross sectional analysis of sleeping patterns in a nationally representative group of elderly people, and longitudinal investigation of mortality. SETTING: Eight areas in Britain (five in England, two in Scotland, and one in Wales). SUBJECTS: 1229 men and women aged 65 and over who in 1973-4 had taken part in a survey funded by the Department of Health and Social Security and for whom data on sleeping patterns, health, socioeconomic circumstances, and cognitive function had been recorded. MAIN OUTCOME MEASURES: Self reported income, access to a car, standard of accommodation, performance on a test of cognitive function, state of health and mortality during 23 years of follow up. RESULTS: 356 people (29%) were defined as larks (to bed before 11 pm and up before 8 am) and 318 (26%) were defined as owls (to bed at or after 11 pm and up at or after 8 am). There was no indication that larks were richer than those with other sleeping patterns. On the contrary, owls had the largest mean income and were more likely to have access to a car. There was also no evidence that larks were superior to those with other sleeping patterns with regard to their cognitive performance or their state of health. Both larks and owls had a slightly reduced risk of death compared with the rest of the study sample, but this was accounted for by the fact that they spent less time in bed at night. In the study sample as a whole, longer periods of time in bed were associated with increased mortality. After adjustment for age, sex, the presence of illness, and other risk factors, people who spent 12 or more hours in bed had a relative risk of death of 1.7 (1.2 to 2.5) compared with those who were in bed for 9 hours. The lowest risk occurred in people who spent 8 hours in bed (adjusted relative risk 0.8; 0.7 to 1.0). CONCLUSION: These findings do not support Franklin's claim. A "late to bed and late to rise" lifestyle does not seem to lead to socioeconomic, cognitive, or health disadvantage, but a longer time spent in bed may be associated with increased mortality.  相似文献   

16.
Spondylolysis and spondylolisthesis occur predominantly in the lower lumbar spine. Besides congenital defects such as predisposition of spondylolysis the correlation between competitive sports activities and an increased incidence of spondylolysis is proved. In early stages, complete healing can be achieved by conservative treatment (abstinence from sports activities for 3 months, orthesis). Persistence of pain, neurologic symptoms and progression of vertebral slipping are indications for operative treatment (reconstruction of the isthmus, dorso-ventral spondylodesis). The exercise tolerance depends on the extent of instability, progression of vertebral slipping and clinical symptoms. The limits of exercise tolerance vary among the individual athletes and require the decision of the physician. Backstroke swimming, abdominal and back muscle strengthening exercises, and types of sport involving smooth movements are advisable. Sports education in school is possible without restriction in patients with stable spondylolysis and in those with spondylolisthesis without unfavourable concomitant factors.  相似文献   

17.
The constructs of intelligence and ego-resiliency are discussed. The personality implications of "pure intelligence" and "pure ego-resilience" were identified. Intelligence (IQ) was indexed by the Wechsler Adult Intelligence Scale-Revised (WAIS—R) and ego-resiliency by an inventory scale. Residual scores measuring "pure intelligence" and "pure ego-resilience" were correlated with the items of the observer based California Q-sort, used to describe participants. Persons relatively high on ego-resilience tend to be more competent and comfortable in the "fuzzier" interpersonal world; persons defined primarily by raw IQ tend to be effective in the "clearer" world of structured work but tend also to be uneasy with affect and less able to realize satisfying human connections. Gender differences exist in the relations of ego-resilience and intelligence and in their adaptive relevance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
Investigated the effects of modeling and corrective feedback on the conservation of equalities and inequalities, with items spanning 3 stimulus dimensions (length, number, and 2-dimensional space). Ss were 48 kindergartners (24 boys, 24 girls). Brief observation of a model, briefer correction training (joining positive feedback with verbal rule provision), and the combination of observation and correction were all successful in producing learning and, without further training, transfer and retention of conservation. Unlike the controls (who also never correctly answered any equality items), the trained experimental Ss gave evidence of spontaneously generalizing their new learning to a task that required nonverbal behavior to manifest conservation. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
Examines strategies that are used to reason about food and contamination. In Exp 1, Ss refrained from choosing a substance that had been given a "poison" label when the intent of the labeler was ambiguous or malicious but preferred this substance when a rationale was provided that dispelled the implication that there once might have been contaminants present. Exp 2 was designed to compare the effects of safety on conditional reasoning in food and food-irrelevant contexts. When the safety issue was relevant to food in the form of contamination, Ss were most likely to use formal logic in reasoning. A similar pattern of responses was found in Exp 3 on tasks for which Ss' ratings of their experience of contexts were matched for plausibility, experience, and danger. Results are discussed in terms of an adaptive constraint that facilitates rationality in reasoning within the food domain (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
根据深云立交桥梁的检测结果,对该桥目前的整体状况、工作状态,及其使用情况做出综合评价,对桥的病害原因进行了分析,并提出合理的加固方案。  相似文献   

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