烧结余热回收系统效率计算及参数动态优化

针对烧结余热回收存在的余热利用率不高、生产不稳定的难题,采用分析方法对某钢铁厂烧结余热回收系统进行研究,建立了评价系统运行效率的效率模型,并对不同运行工况下系统效率进行了计算分析.在此基础上,建立效率优化模型,并通过粒子群算法进行求解.根据不同入口余热资源量动态地调整蒸汽参数设定值,从而增加系统对变工况运行环境的适应能力.基于工业运行数据的仿真结果表明,动态优化法可使烧结余热回收系统的效率提高4%~11%.     

大型低速船用柴油机余热回收装置的平衡分析

介绍了当前一般船用柴油机的余热回收装置,对特定型号主机废气余热回收装置进行平衡分析,通过计算求出了该装置的分配及利用情况,以及各装置效率的潜在提高程度.结果表明,该余热回收装置具有较高的效率和较好的经济性.分析的结果可以指导人们合理的提高的利用效率.     

炼铁系统余热余能利用

通过调研国内炼铁系统余热余能资源量及回收利用现状,对高炉炼铁系统进行了热量和质量平衡分析,并分析了烧结、焦化、炼铁工序的节能潜力.介绍了CMC、CDQ、TRT、CCPP等炼铁系统的主要节能技术及应用现状,最后对烧结余热的回收原则及发电技术的研发进行了探讨.     

炼铁系统余热余能利用

通过调研国内炼铁系统余热余能资源量及回收利用现状,对高炉炼铁系统进行了热量和质量平衡分析,并分析了烧结、焦化、炼铁工序的节能潜力。介绍了CMC、CDQ、TRT、CCPP等炼铁系统的主要节能技术及应用现状,最后对烧结余热的回收原则及发电技术的研发进行了探讨。     

用于丝光印染淡碱回收的热泵蒸发系统的分析

确定了用于丝光印染淡碱回收的热泵蒸发技术的工艺流程,运用分析法对系统的主要部件建立了分析模型,并根据系统的平衡原则,计算得到的平衡相对误差仅为1.1%,具有足够的精度,满足工程计算和分析要求.分析结果表明:系统效率为4.8%,压缩机、蒸发器、水泵及排放的损失是系统损失的主要部分,分别为36.9%,31.2%,19.0%和9.2%.由此可见,热泵蒸发技术虽然充分回收利用了二次蒸汽的余热,具有较高的热效率,但效率仍然很低,且损失主要来自压缩机及蒸发器,占总数的68%.因此系统在设计及改进时,应着重减少压缩机和蒸发器的不可逆损失,压缩机工作时尽量接近绝热压缩过程,提高定熵效率,而在蒸发器中尽量选择较小的传热温差.     

基于平衡的微型燃气轮机回热循环效率分析

对采用回热循环的微型燃气轮机进行了正、反平衡效率分析,推导了正、反平衡效率一致性的数学模型.结合微型燃气轮机实例,计算了正、反平衡的效率,并进行了分析的可靠性检验,检验结果表明,实例中的正、反平衡效率偏差和偏差率都很小,分析结果可靠.通过反平衡效率分析,得出了微型燃气轮机的主要损部位,提高微型燃气轮机效率可主要从改进燃烧室和回热器入手,对于排气中的损失可采用结合余热利用装置加以利用.     

烧结余热发电高温烟气阀门设计

烧结工序的能耗指标与先进国家相比差距较大,每吨烧结矿的平均能耗要高20千克标准煤,节能潜力很大.烧结工序的能耗约占冶金总能耗的10%～12%.而其排放的余热约占总能耗热能的49%.在烧结矿生产过程中,特别是烧结矿由鼓风式环冷机冷却过程中会排出大量温度为250～400℃的低温烟气,其热能量大约为烧结矿热耗量的30%左右.实现能源梯级利用的高效性和经济性角度分析,余热发电是最为有效的余热利用途径,平均每吨烧结矿产生的烟气余热回收可发电20千瓦时,折合吨钢综合能耗可降低8千克标准煤.余热发电烟气阀门烧结余热发电重要的辅机设备,直接影响烧结和余热电站运行稳定、废气的充分利用以及整个系统运行效率和可靠性,做好高温烟气阀门对烧结余热发电具有重要意义.     

基于产热量优化的烧结余热回收操作参数设定

针对钢铁烧结余热回收过程中的热交换效率优化问题，引入锅炉有效产热量的概念，用于评价余热发电系统的整体运行效率，提出基于中压锅炉有效产热量优化的余热回收过程操作参数设定方法.首先应用BP神经网络对中压锅炉有效产热量进行预测，基于热力学原理建立有效产热量优化模型；然后采用一种改进的粒子群优化算法求解优化模型，得出有效产热量最大时中压蒸汽温度和环冷机速度的优化设定值.基于工业运行数据的仿真结果表明，所提方法可以使烧结余热回收系统的有效产热量平均提高5%左右，从而提高余热发电效率.     

氯化铵回收的三效降膜蒸发系统的分析

利用黑箱和灰箱模型对氯化铵回收三效降膜蒸发系统进行了分析,找到了系统损的关键,即二次蒸汽的消耗引起的外部损．对各效蒸发器采用白箱模型,分析了蒸发器损的主要环节,结果表明,对于一、二、三效蒸发器,传热温差引起的损率分别为77．64％、68．59％和75．87％,降低传热温差引起的损是提高蒸发系统效率的主要途径．由于浓缩热引起的损也是不容忽视的,应提高系统的真空度,采用低温蒸发路线．     

褐煤提质联产油工艺的数值模拟与分析

通过褐煤提质联产油工艺(LFC)实验装置进行芒来褐煤热解提质实验,取得流程模拟中需要的原始数据,在对LFC工艺流程模拟的基础上,对其进行分析,计算各操作单元的损失,分析损失产生的原因,指出提高效率的方法。结果表明:原煤处理量为1000.00 kg/h时,须补充甲烷37.80 kg/h;损失的主要原因是由于热量传递的不可逆性和化学反应的不可逆性;LFC工艺的效率为74.39%,可以通过改进工艺、回收利用半焦和热解气的物理来提高系统的效率。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.