大型空分设备气体放空的噪声控制与治理

文章简介了空分设备气体放空时产生的噪声对周围环境的污染和伤害,并对放空气体噪声的控制与治理进行了分析对比;提出大型空分设备,特别是内压缩流程的空分设备,大流量低、中、高压气体放空,应采用消声塔集中排放,有效控制和治理气体放空噪声。     

加氢制氩与无氢制氩流程结合制取纯氩的实践

酒钢动力厂6000m3/h空分设备制氩系统采用加氢制氩流程,将经过粗氩压缩机压缩、冷却并干燥后的粗氩气,引入到21000m3/h空分设备的全精馏无氢制氩系统中,实现了对加氢制氩流程的改造,有效地减少了设备操作和维护成本,并且停运了制氢站,获得了较好的经济效益和社会效益。     

60000m~3/h空分设备物料平衡及变负荷控制原理

文章以60000m3/h空分设备为例,以理论计算为基础,从物料平衡角度出发,介绍空分设备的自动变负荷的控制原理和计算。实际运行证明,自动变负荷控制系统运行效果较好。     

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增压膨胀和全精馏无氢制氩技术在1000m~3/h空分设备上的应用

介绍采用增压膨胀和全精馏无氢制氩技术的1000m3/h空分设备的流程设计和技术指标,简述了安装调试中遇到的问题以及解决方法。     

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描述了HYSYS过程模拟软件在空分设备操作中的应用,并介绍了软件应用过程中的体会。     

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对63MN五坐标数控快锻机在自由锻和恒温锻不同的工艺过程进行分析,根据压机设备压力高、流量大的特点,进行系统的优化设计。并对降低噪声、抗污染、保证系统可靠性、实现系统的高精度、高响应等要求,提出了合理的设计方案。     

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On the large deviations approximation for the stationary distribution of skip-free regulated queueing networks

Large deviations papers like that of Ignatyuk et al. [Russ. Math. Surv. 49 (1994) 41–99] have shown that asymptotically, the stationary distribution of homogeneous regulated networks is of the form

with the coefficient being different in various “boundary influence domains” and also depending on some of these domains on n. In this paper, we focus on the case of constant exponents and on a subclass of networks we call “strongly skip-free” (which includes all Jackson and all two-dimensional skip-free networks). We conjecture that an asymptotic exponent is constant iff it corresponds to a large deviations escape path which progresses gradually (from the origin to the interior) through boundary facets whose dimension always increases by one. Solving the corresponding large deviations problem for our subclass of networks leads to a family of “local large deviation systems” (LLDSs) (for the constant exponents), which are expressed entirely in terms of the cumulant generating function of the network. In this paper, we show that at least for “strongly skip-free” Markovian networks with independent transition processes, the LLDS is closely related to some “local boundary equilibrium systems” (LESs) obtained by retaining from the equilibrium equations only those valid in neighborhoods of the boundary.

Since asymptotic results require typically only that the cumulant generating function is well-defined over an appropriate domain, it is natural to conjecture that these LLDSs will provide the asymptotic constant exponents regardless of any distributional assumptions made on the network.

Finally, we outline a practical recipe for combining the local approximations to produce a global large deviations approximation , with the coefficients K_j determined numerically.