石油化工建设中压力管道是不可或缺的承压类特种设备之一,因其所承载的介质具有易燃、易爆、高温、高压、易腐蚀的性质,在安装过程中需要严格控制.从压力管道的材料,预制,安装等多方面论述如何控制压力管道安装的质量.

The Sherritt Zinc Pressure Leach Process has been applied successfully at the HBMS zinc plant in Flin Flon,Manitoba since 1993.The HBMS plant was the first commercial application of the two-stage zinc pressure leach process,which allows for 100%production of zinc by direct leaching,in the absence of roasters. Full design capacity in the pressure leach plant was established within a month of commissioning the two-stage process in Flin Flon and additional zinc production has been achieved using the same leach vessels following installation of a larger cellhouse in 2001.Operating data collected since start-up of the zinc pressure leach plant are discussed in this paper,along with a description of minor element behavior.

The three nickel projects located in Western Australia-Bulong,Cawse and Murrin Murrin-produce metallic nickel via pressure acid leaching to treat lateric ore.In each of the major process steps,different engineering approaches have been adopted.This paper compares these approaches.

研究了一种简单的从电解锌流程中产生的Cd-Cu-Zn滤饼中选择性回收镉的湿法工艺.镉的浸出、过滤和再浸出常规流程需多个阶段,成本较高.此研究的目的是寻找一种更简单的方法从电解锌流程锌净化阶段的Cu-Cd滤饼中回收镉.所研究的流程包括从Cu-Cd滤饼中除去锌,选择性浸出镉和通过去除Fe、Tl和Co,净化之后再进行电解和熔铸.Cu-Cd滤饼中的锌通过两个阶段转移至液相中,铜和镉在滤饼中富集.在较高的固液质量体积比条件下从滤饼中选择性浸出镉,溶液中镉的浓度较高.在特殊条件下选择性浸出镉可使富镉溶液中共同沉淀的杂质最少.浸出反应在铜的溶解开始时停止.用KMnO4和NaOH氧化和沉淀杂质,如Fe、Tl和部分Co.净化后的硫酸镉溶液通过电积得到阴极镉,然后熔铸得到99.95%的金属镉.整个流程中,镉总回收率为70%～72%.

In hydrometallurgical processes,the use of metal sulphide instead of hydroxide precipitation has gained prominence in recent decades.The arguments for its preferential use are based on the high degree of metal removal at relatively low pH values;the sparingly soluble nature of sulphide precipitates;favourable dewatering characteristics and the stability of the metal sulphides formed.However,when choosing a metal sulphide precipitation route,various difficulties are encountered,two of which are described in the current work. The first issue is that these metal sulphide processes,dominated by low solubilities and high supersaturation levels,favour the formation of fine particles due to the dominant mechanisms of homogeneous nucleation,aggregation and attrition. The second issue is that,in areas of high local sulphide concentration,the excess sulphide can lead to the formation of aqueous polysulphide complexes,which consume the sulphide reagent and compromise the metal removal.