General:
The coal elements content are the essential indexes and parameters of manufacturing process in electric power and chemical industry. Nowadays, the analysis of the coal elements, which is usually done by artificial operation, including sampling, making sample, and doing the chemical analysis, is a comparatively long period with the inevitably big errors when doing sampling and making sample, and tends to be easily influenced by the human elements. For example, certain of poor quality coals and coal gangue have frequently been deliberately mix into the coal as received, but it difficult to be disclosed by the traditional analysis method by sampling and sampling making, and it has been a great loss to customers long time. During the manufacturing process of thermal power plant, the quality of the coal as fired is a essential parameter influencing the safe and economic functioning of the boilers. For the analyzing period of traditional analyzing method is too long long to catch up with the request of the production. If encounters the poor quality coal and big coal flow wave, not only the boiler functioning efficiency will be greatly reduced, but also breaks out the sudden stop and flameout, all these severely influenced the safety and economy of the thermal power plant. Through the coal online analyzer, the coal content could be accurately figured out, which bring a lot of convenience for the operator to adjust the combustion, so as to ensure the safety and stable running of the units. Thus, the coal on-line analyzer is of very significant importance for the safety and economy of manufacture in flow industries.

Measure principle:
The coal on-line analyzer adopts the neutron activation technology, which produce the prompt γ rays and combine the thermal neutron capture reaction with the fast neutron non-elastic scattering reaction, realizes the online analyzing of all elements.。The nuclear reaction between high energy neutron and elements in coal produces the prompt γ ray with the corresponding characteristics of the reacted elements. By the measurement result on the energy of the characterized γ ray, the corresponding element can be identified and by the quantity of the characterized rays the content of the all elements can be determined.

Functions:
1. To directly measure the contents of all elements in coal, including C, H, O, N, S, Al, Si, Fe, Ca, etc. Meanwhile, it can do the ultimate analysis by the trace elements like Ti, Na, K in coal.
2. To provide the proximate analytical data of coal, including calorific value, volatility value, ash content, moisture and fixed carbon content.
3. To provide the combustion characteristics of coal, including the indexes such as the ash soften temperature and the coking index.

Physical Framework:

The coal online analyzer mainly consists of the measurement and shielding system, the spectral analysis and control system and the computer process system. When the coal flow comes exposed to the emission source inside the analyzer which is across on the coal conveying belt, the neutron radial emitted by the neutron generator irradiates the coal flow and radiates the γ rays, and then the BGO detector receives the γ rays and converts it into the photoelectric signal, and the photoelectric signal will be finally transmitted to the energy spectrum analysis unit for analysis, it turns out to be the elements content, which can diagnoses material characteristics through the proximate analysis transition unit and material characteristics analysis system.