Drop-shatter test

The drop shatter test indicates the resistance of a coal or coke to breakage on impact (see D440). A sample is dropped in a standard way a number of times from a specified height. Eor the tumbler test or abrasion index (ASTM D441), the coal or coke is rotated in a dmm to determine the resistance to breakage by abrasion (18). 

The physical strength of the raw anthracite, as indicated by the ASTM tumbler and drop-shatter tests for coke (I, 2), is inferior to that of metallurgical coke. 

ASTM D-440. Standard Test Method of Drop Shatter Test for Coal. 

ASTM D-3038. Standard Test Method for Drop Shatter Test for Coke. 

D 440 - 37 T. Tentative method of drop shatter test for coal. Part III, pp. 570-575. 

Leaving aside single particle impact tests which fall into section 6.1, the most common type of multiparticle impact tests are drop shatter tests in which a specified quantity of the test material is dropped through a specified height onto a hard surface or into a container. National and international standards exist on drop shatter tests for coke and coal and similar tests are also applied to iron ores and sinters. Drop shatter tests are in general used on coarser solids than those within the scope of this guide the fine fraction is in fact often removed from the bulk material before the test. 

A drop shatter test has also been described for determining the friability of coal (ASTM, 2011e) which is similar to the standard method used as a shatter test for coke (ASTM, 2011m). In this method, a 50 lb sample of coal (2-3 in. [4.5-7.6 cm]) is dropped twice from a drop-bottom box onto a steel plate 6 ft below the box. The materials shattered by the two drops are then screened over round-hole screens with 3.0 in. (76.2 mm), 2.0 in. (50.8 mm), 1.5 in. (38.1 mm), 1.0 in. (25.4 nun), 0.75 in. (19.05 mm), and 0.5 in. (12.7 mm) openings and the average particle size is determined. 

ASTM. 201 Id. Standard Test Method for Grindability of Coal by the Hardgrove-Machine Method (ASTM D409). Annual Book of Standards, American Society for Testing and Materials, West Conshohocken, PA. ASTM. 201 le. Method for Drop Shatter Test for Coal (ASTM D440). Annual Book of ASTM Standards, Section 05.05. American Society for Testing and Materials, West Conshohocken, PA. 

There are, for example, various drop shatter tests in which the material falls under gravity onto a hard surface or a fixed bed. Such a test was carried out by Zenz and Kelleher (1980), who considered catalyst attrition due to free fall in a CFB downcomer. However, the probably most relevant impact tests are those where pneumatically accelerated particles are impacted onto a target. Yuregir et al. (1986, 1987) pioneered this type of test in their work on NaCl salt. In the meantime, such test devices have found broad industrial application as friability tests. For example. Fig. 8 shows the setup used by Davuluri and Knowlton (1998). It requires approximately 100 grams of material to conduct a test. The velocity at which the solids strike the impact plate was varied from 46 to approximately 144 m/s, but in the upper range a material-specific threshold velocity exists, above which the particles completely shatter. This is for most materials a velocity greater than 76 m/s. If velocities above the threshold... 

Cubic Foot Weight of Crushed Bituminous Coal Drop Shatter Test for Coal Dustiness, Index of, of Coal and Coke Fusibility of Coal Ash... 

The first is the strength of anti-fracture. This experimental method is divided into single particle crush strength (SPCS), the whole stack crush strength (WSCS) and the drop-shatter test. 

The drop-shatter test. The impact caused during the process of catalyst loading is much larger than that during the process of catalyst transport, so the strength of the catalyst (especially tablets) can be expressed by the drop-shatter test. 

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