炭黑在气力输送管道中的压力损失研究

对以炭黑为输送对象的气力输送管道中水平管、垂直管和弯管的输送压力损失分别进行了分析,得到了炭黑在这3种输送管道中的压力损失计算公式.该公式可作为工程上分析炭黑与气体混合流在输送管道中压力损失的经验公式.     

炭黑气力输送流动特性研究

对气力输送过程中炭黑的流动特性进行了试验研究.依据试验结果,分析了炭黑的粒径大小与输送管道阻力、输送压力与输送管道压力损失、气体流量与炭黑的质量流量、输送压力与炭黑粒子破碎率之间的关系,为炭黑气力输送系统的设计及其工艺参数的确定提供参考.     

炭黑气力输送中粒子破碎问题及对胶料的影响

分析炭黑粒子破碎率对炼胶工艺的影响及气力输送中炭黑粒子破碎的原因,指出炭黑比表面积、炭黑粒径分布、输送压力参数、输送方式、输送管材料和输送距离是影响炭黑破碎率的主要因素。通过对压送罐开启压力、主管压力、辅管压力、结束弯管压力和辅管开启压力进行优化,可相应减小输送时的炭黑破碎率;采用密相输送、选择摩擦因数较小的管道材料和尽量减小输送距离也可减小输送时的炭黑破碎率。     

炭黑密相气力输送节能分析

从炭黑密相气力输送气源供给压力、双管输送辅助管补气方式及可调式LAVAL管等方面分析了针对炭黑密相气力输送节能的可行性以及节能空间.指出通过采用可调式LAVAL管降低气源压力和可控式辅管补气方法,可大大降低炭黑密相气力输送的空气量和能耗,降低生产成本.     

在气力输送弯管中炭黑的输送特性分析

研究炭黑(固相颗粒)在气力输送通过弯管时,弯径比(δ)对输送弯管内压力损失和固相颗粒运动速度以及弯管内壁磨损的影响。当δ小于5时,随着δ的增大,输送弯管内压力损失减小和固相颗粒运动速度增大,弯管内壁磨损程度降低;当δ增大到5后,输送弯管内压力损失和固相颗粒运动速度以及弯管内壁磨损速率变化放缓。设计炭黑气力输送弯管时,δ在5～7范围内既可以使输送弯管内壁磨损程度和输送能耗降低,又可满足输送管道布局和工艺要求。     

炭黑在气力输送过程中破碎率的影响因素分析

介绍了在气力输送系统中炭黑的破碎机理,分析了炭黑破碎率的影响因素,指出炭黑品种,炭黑的堆积密度、压碎强度和不同粒径质量分布等物性,输送管道长度及其布置、输送压力和炭黑输送速度等工艺参数是影响炭黑破碎率的主要因素,并通过实验结果进行了论证.     

气力输送过程中炭黑粒子破碎率影响因素分析

分析气力输送过程中炭黑粒子破碎率的影响因素。炭黑品种及造粒方式、炭黑粒子压碎强度、输送距离、输送气速、输送方式、输送管道清扫对炭黑粒子破碎率的影响较大。综合考虑各方面因素,对气力输送系统优化提出建议:湿法造粒炭黑粒子破碎率明显小于干法造粒炭黑,应按造粒方式分别设定炭黑粒子破碎率指标,炭黑造粒应优选湿法造粒工艺;为了保证输送后炭黑粒子破碎率小于10%,炭黑粒子压碎强度应大于30 g,同时炭黑粒子压碎强度分布不宜过宽;在气力输送系统中采用比例调速阀,通过自动控制系统自动调节炭黑输送气速,以实现不同炭黑在最佳状态下输送;尽量减小管道清扫次数。     

炭黑气力输送系统的改造

介绍了轮胎厂炭黑气力输送系统的结构和工作原理,并对其进行改造。将原同径输送主管改为较大通径且逐渐增大,增大了文丘里阀口径,增加管道压力传感器数量和将单辅管补气改为双辅管补气后,对炭黑N330进行输送前后破碎率试验,结果表明改造后大大减小了炭黑破碎率,由于增大管径并加固输送管路,还减小了管路振动,避免了炭黑泄漏。     

气力输送过程中物料破碎率的研究

气力输送过程中影响物料破碎率的因素很多,包括气力输送的形式、物料的物性、输送管道的布置、输送系统的工艺参数等.本文以炭黑气力输送系统为例,研究了减少炭黑破碎率的方法及炭黑破碎率的测量方法.并利用MATLAB神经网络对炭黑的破碎率进行预测.     

炭黑密相气力输送系统设计

随着橡胶工业的发展，以及气力输送特有的优点，气力输送系统越来越广泛地应用于输送炭黑的过程中。以炭黑气力输送系统为研究对象，详细介绍了系统设计的基本参数确定、气力输送形式的确定、压送罐客积的设计、输送管道的设计，并通过输送系统压力降的计算验证了设计参数的取值是合理的。     

炭黑气力输送中破碎率及气量控制的试验研究

近年来，随着气力输送行业的发展，人们对输送后物料的破碎率要求趋于苛刻。在炭黑密相气力输送试验的基础上，对炭黑输送中的破碎率进行了正交试验，并研究了输送气量控制、气速对破碎率的影响，认为气速是影响粒子破碎率的主要因素，在保证输送正常（不堵管）的情况下，降低输送气速，可大大地降低炭黑在气力输送中的破碎率。     

石灰石粉密相气流输送中试研究

用石灰石粉进行长度分别为62m和167m两种不同输送距离、管径为80mm的中试研究，通过获得的有关水平管、垂直管、弯管的压降数据及不同输送距离条件下的固气比数据，提出了密相技术输送这种粉料的压降的关联式和固气比关联式，再通过计算程序，可以较好地模拟实验过程，说明所获得的计算关联式可以用于石粉输送的工艺设计，为石粉的输送工程设计奠定了基础。     

用MATLAB神经网络预测气力输送过程物料破碎率

物料在气力输送过程中的破碎率大小,是评判气力输送系统及输送工艺优劣的重要参数之一.利用MATLAB语言,将炭黑气力输送系统各位置的压力数据输入BP神经网络,用训练好的网络模型进行仿真,对炭黑的破碎率进行了预测.与实验结果对比,采用BP神经网络对炭黑破碎率的预测具有比较高的精确度,可对气力输送系统的优化设计以及输送工艺参数的优化选取提供指导.     

Die Grundlagen der pneumatischen Förderung

Principles of pneumatic conveying . The design of pneumatic conveying systems is critically dependent upon a knowledge of the pressure drop and the minimum necessary velocity of the conveying gas. Starting from the areas of application of pneumatic conveying systems, the conveying states occurring are discussed and appropriately assigned to the diagram of state. The pressure loss equation is reported for conveying in form of a fully suspended flow and strand-type conveying and the theoretically predicted pressure losses are compared with experimental values for the conveying of coarse and finegrained materials. After mentioning the calculation of the pressure drops due to acceleration and to pipe bends, the article discusses the problem of pipe enlargement for long conveying distances. Equations are also given for the calculation of the so-called blocking limit and of the conveying gas velocity at which the minimum pressure drop occurs. The influence of the compressor on the choice of the operating point is also discussed. New calculation equations are then given for horizontal and vertical conveying in form of a fully suspended flow conveying and for horizontal strandtype conveying which permit reliable scale-up. Moreover, a new equation is reported for the blocking limit in horizontal conveying.     

某厂长距离磷矿浆输送方案的比较和选择

磷矿浆长距离管道输送在国内尚属新技术，介绍了某厂采用该技术的具体情况，磷矿浆长距离管道输送的设计要点，探讨了磷矿浆中ω固目对其黏度、管径大小和压力损失的影响，经综合比较推荐采用ω固=40％的磷矿浆，以保证操作过程中系统稳定运行。     

Horizontal pneumatic conveying from a fluidized bed

In this paper the feasibility of feeding a horizontal pneumatic conveying line directly from a fluidized bed is explored by investigating the relationships governing the solids mass flow rate in such a pipe as a function of both pressure drop and pipe length. Three different materials were fluidized by air and discharged though a 25 mm internal diameter pipe. Materials used were turnip seeds of mean diameter 1.5 mm, carbon steel shot of mean diameter 0.73 mm and plastic pellets of mean diameter 3.76 mm. Several pipe lengths were used, from 0.75 to 1.77 m. The experiments showed that it is feasible to feed directly from a fluidized bed to a horizontal pneumatic conveying line. The flow regime in the pipe was that of dense phase conveying also called slug flow. The data collected show that there is a clear relationship between the pressure drop down the conveying line and the discharge rate of solids from the line. The discharge rate is also dependent on the pipe length.In previous studies of pneumatic conveying, the solids and gas mass flow rates have been independently set, which cannot be done if the conveying line is fed from a fluidized bed. For a pipe fed from a fluidized bed, the solid and gas mass ratio are coupled and this was modelled using the theory for air-augmented granular discharge through an orifice in a hopper or silo of Nedderman et al. [1983. The effect of interstitial air pressure gradients on the discharge from bins. Powder Technology 35, 69-81], but as modified by Thorpe [1984. Air-augmented flow of granular materials through orifices. Ph.D. Thesis, University of Cambridge] for horizontal discharge. This was then combined with a modification of the theory of Konrad [1981. Ph.D. Dissertation, University of Cambridge] to give a prediction of the total pressure drop and the gas and solid mass flow rates. This combined model for dense-phase conveying from a fluidized bed was found to give an excellent fit to the data using the standard values for the constants in every equation. The predictions of the combined model also agree well with the experiments of Konrad [1981. Ph.D. Dissertation, University of Cambridge] for discharge from a hopper into a horizontal conveying line.     

炭黑气力输送形式的对比分析

为保证橡胶厂炼胶质量的均一稳定和炼胶车间的环境整洁,作为补强剂的炭黑采用气力输送方式是必然的。分析了不同炭黑气力输送形式的工作原理、性能特点及主要优缺点,重点探讨了炭黑正压密相气力输送形式的结构组成、设计流程、主要零部件的设计,为正确选择和设计炭黑气力输送系统提供依据。