The Development Of Portable Ash Detector Based On Low-energy Gamma-ray Method

The ash content of coal is an important index in coal trade and utilizing process. But presently , mining companies and coal consumers commonly use the coal proximate analyzer to get the coal ash content. This method is so slow in process that we can't obtain the ash content of coal in time, it can far from meeting the need of coal trade and use. But advanced rapid ash analysis apparatus are very expensive and require strict installing conditions which are a serious economic problem for many companies and customers during application. Therefore, it is especially important to use a rapid, but simple and effective way of ash measuring during coal trading and utilization.According to the situation, a rapid portable ash detector based on dispersion of low energy gamma ray was developed in this paper. The paper takes the practical conditions that used in outdoors into consideration, it chooses an appropriate NaI(Tl) as the detector and a appropriate radiation which is Am 241; The PCB and the whole configuration of the portable ash detector, as well as the safety accessing was studied. After the setup of the ash-meter, the relationship between intensity of gamma ray and content of ash was studied; it gives separate investigation on the apparatus's precision affected by the proportion of moisture content, the proportion of containing-iron, the degree of fragmentation and the degree of condensation. At last, according to the analysis of the experiment data, it gives the solution to correct the influence of the factors which will have certain influence to the measurement, as well as the operation instruction for operation.