X-ray or gamma ray systems or devices – Specific application – Fluorescence
Patent
1997-05-01
1998-02-24
Wong, Don
X-ray or gamma ray systems or devices
Specific application
Fluorescence
378 44, G01T 136
Patent
active
057217599
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to a method for determining the content of an element from a flowing sample mass by utilizing x-ray fluorescence, in which method sample mass is determined, and spectrum on the basis of the intensity of the radiation spectrum window characteristic of this element.
BACK OF THE INVENTION
A detector in a measuring equipment utilizing x-ray fluorescence detects photons which develop into an energy-dispersive radiation spectrum (intensity) as a function of wave length or energy from which sequences representing each element are selected by means of electronics and/or software. These sequences are known as energy windows, i.e. channels. The pulses (intensities) gathered to the channels are used in analytical calculation. Several so called background channels or scattering channels in different energy areas are also selected from the spectrum by means of which channels information is gathered on the total amount of the mass to be measured and its distance with respect to the detectors.
Analytical methods based on x-ray fluorescence can be applied in an industrial process for determining the element content of a flowing sample mass. By means of the method, the elements can be measured directly from the mass flow, the amount of which can vary. In a typical solution, elements of crushed ore are measured directly from above a conveyor. Various mineral concentration plants, quarries, cement industry and other branches of chemical industry need exactly this kind of a method for measuring elements directly from the process flow. Generally, the object is to perform the measurement at such accuracy and speed that the process can be controlled and adjusted in real time by means of the obtained measuring result.
Element analyzers based on x-ray fluorescence are widely used in laboratories. The measurement of a fine-crushed sample is increasingly performed by means of process analyzers which cannot, however, be used for measuring a material which typically has a larger granular size than 1 mm.
Nowadays there are also in use apparatuses and methods based on x-ray fluorescence for measuring elements directly from above a belt or through a belt from a mass flow. For example, Ima Engineering Ltd. Oy, Espoo, Finland manufactures and sells Beltcon 100 and Beltcon 200 analyzers for the above-mentioned purposes. A problem of both apparatuses is especially the inaccuracy of their measurement results in varying environmental conditions. Especially the measuring of light elements, such as calcium by means of a fixedly installed measuring equipment has been found to be difficult as the intensity of the characteristic x-ray radiation attenuates in proportion to the square of distance. Therefore, the measuring distance should be as small as possible when measuring light elements, such as Ca, K, Si and Al.
The object of the present invention is to measure and analyze accurately the element contents of crushed and/or fine-crushed ore by means of the x-ray fluorescence principle in real time directly from above the conveyor so that it is possible to adjust the process in real time on the basis of the element contents.
SUMMARY OF THE INVENTION
The object of the present invention is also to compensate automatically the variations in the distance between the mass and the measuring equipment, as well as the changes in the conditions of the measuring environment.
Another object of the invention is to ensure the ability of the measuring equipment to function against both momentary and long-term variations.
A further object of the invention is to measure even light elements reliably and accurately.
Still another object of the invention is to disclose a method and equipment with which element contents can be measured and analyzed by means of the x-ray fluorescence principle from a mass flow which can be solid, slurry or liquid matter.
In order to solve the above-mentioned problems and to achieve the objects, the method of the invention further comprises steps in which radiation detector or
REFERENCES:
patent: 4015124 (1977-03-01), Page
patent: 4045676 (1977-08-01), Rolle
IMA Engineering Ltd. Oy
Wong Don
LandOfFree
Method and equipment for determining the content of an element does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and equipment for determining the content of an element, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and equipment for determining the content of an element will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1879613