ISO 923:2000 pdf free

ISO 923:2000 pdf free.Coal cleaning equipment一Performance evaluation
The equipment to be tested, the feed composition, and the means of handling the feed and products, vary widely. A single International Standard to cover all cases is not applicable. The following general procedures shall be followed.
a) Samples shall be taken from the feed and from each of the products. The sampling techniques, number of increments and increment mass shall ensure that all samples taken are representative and shall comply with existing International Standards where available. Sampling of coal is covered by ISO 1988 and size analysis of coal is covered by ISO 1953.
To enable checking of results and assessment of the effects of degradation, representative samples should be taken from all relevant streams to and from the equipment to be tested.
b) It is essential to determine the feed rate and the percentage yield to each of the products on a dry basis in accordance with ISO 1170. This should be achieved in accordance with one of the procedures given below.
Determine the mass of each product by one or more of the following methods, which are listed in order of reliability.
a) By direct weighing of the whole of each product collected over the duration of the test or through continuous weighing and integration over the duration of the test.
b) By taking regular timed increments over the duration of the test.
c) By weighing each product cllceted simultaneously over a selected period of the test.
NOTE 1 If it is feasible to measure both the mass of the feed (by belt weigher, weigh hopper, flowmeter, etc.) and the mass of the products, this provides a check.
NOTE 2 If the mass of one of the products cannot be obtained, it may be derived from a mass balance between the feed and other product(s).
NOTE 3 Where the solids are conveyed by a fluid, it may be more convenient to make volumetric measurements. Representative samples should be taken from streams to determine moisture content or concentrations of solids as appropriate, so that results can be reported on a dry basis.
In circumstances that prevent the determination of yields by the above procedures, alternative procedures (e.g. ash balance) may be used.ISO 923 pdf download.