Standardization of a Calcined Coke Bulk Density Test

Abstract

One of the major factors affecting Hall cell anode performance is the porosity of the calcined coke used in its manufacture. Relatively simple, rapid, and inexpensive bulk density tests can give a good indication of coke porosity. However, without an industry-wide standard test, comparison of coke bulk density results among various suppliers and users is meaningless. A standard test is being developed under the sponsorship of ASTM Committee D-2 on Petroleum Products and Lubricants. This paper describes some of the bulk density tests currently used and their short-comings. Effects of crushing equipment and strategy are shown. In most coke bulk density tests, mechanical action such as vibration is used to increase sample compaction. Selection and calibration of a vibrator and ancillary equipment are discussed. Efforts to reduce test result differences due to operator variability are described also.