Method for eliminating influence of radon and radon daughters upon polypropylene process and radioactive instrument

Abstract

The invention discloses a method for eliminating influence of radon and radon daughters upon polypropylene process and a radioactive instrument. The method is aimed at solving problems arising from conventional polypropylene process. A great discrepancy between display of the instrument and actual material occurring in case of sudden abnormity for alarm of continuous material level and high-and-low material level is avoided. Even when material is present in the conventional reaction kettle, zero material level or negative material level is displayed by a level gage. In order to solve the above problems, the method is characterized in that the outer wall of a detector is wrapped in a layer of lead sheath; and a 6mCicaesium-137 radioactive source is adopted by a radioactive source. The method for eliminating influence of radon and radon daughters upon polypropylene process and the radioactive instrument has following beneficial effects: the 6mCicaesium-137 radioactive source is adopted so as to reduce the proportion of gamma rays emitted from radon and radon daughters received by a detector and a measurement condition for the level gauge is satisfied; by protecting the outer wall of the detector with lead, environment interference is reduced and high pressure of the instrument and activity of the radioactive source are improved in order to increase pulse received by the instrument, prolong delay time of the instrument and prevent the environment influence upon the instrument from generating fluctuation; and when material is not fed, the zero point in the thermal state of the instrument is calibrated by increasing temperature and pressure

Description

technical field [0001] The invention belongs to the field of polypropylene production; in particular, it relates to a method for eliminating the influence of radon and radon daughters on polypropylene technology and radioactive instruments. Background technique [0002] The radioisotope instrument for polypropylene process is generally based on the penetrability of nuclear radiation and the radiation absorption characteristics of the material. The main structure includes three parts: radiation source, detector and display instrument. Radioactive elements generally have alpha, beta, gamma and x-rays. Alpha ray is a positively charged high-speed proton flow. Its charge is equivalent to two electron charges, and it is composed of a cyanogen nucleus that has lost two electrons and has two neutrons. Its penetrating ability is weak. Beta rays are high-speed streams of negatively charged electrons. Its charge is an electronic charge, and its mass is much smaller than that of α pa...

AI Technical Summary

Problems solved by technology

[0005] The present invention aims to solve the problems of the continuous material level of the reactor and the sudden abnormality of the high and low level alarm in the existing polypropylene process, which is manifested as a serious discrepancy between the instrument display and the actual material, and even