Sampling device of thermal gravimetric analyzer

Abstract

The invention belongs to the field of thermal gravimetric analyzers and discloses a sampling device of thermal gravimetric analyzer. The sampling device of the thermal gravimetric analyzer comprises a screw powder adder, a reaction container, a thermocouple, a motor and a vacuum pump, wherein the screw powder feeder comprises a powder feeder main body and a screw rod; a powder feeder inlet and a powder feeder outlet are arranged at the top and the bottom of the powder feeder main body respectively; the reaction container is hollow and the upper end is open for receiving a sample falling off from the powder feeder outlet; the thermocouple is connected with the reaction container; the screw rod comprises a rod body and an outer thread arranged on the side wall of the rod body; the rod body is of an internal hollow structure; the vacuum pump is arranged at the upper part of the screw rod for extracting the residue. According to the sampling device of the thermal gravimetric analyzer, the base line drift of a thermogravimetric curve caused by buoyancy and convection and influence of convection caused by a temperature difference between inside and outside of a thermobalance on the weighing accuracy are improved and the measurement accuracy is improved.

Description

technical field [0001] The invention belongs to the field of thermogravimetric analyzers, and more specifically relates to a sampling device for thermogravimetric analyzers. Background technique [0002] At present, precision thermogravimetric analyzers are aimed at small mass samples. Many powdery solid particles such as coal powder, biomass and other organic matter need to be experimentally studied on a thermogravimetric analyzer. Thermogravimetric analysis is a standard method for measuring coal powder, biomass particles and other organic matter. On the current thermogravimetric analyzer, the baseline drift of the thermogravimetric curve caused by buoyancy and convection and the convection caused by the temperature difference inside and outside the thermobalance will affect the accuracy of weighing. The packing is tight, and the contact between the sample particles is good, which is conducive to heat conduction, but not conducive to gas diffusion. The filling is require...

AI Technical Summary

Problems solved by technology

On the current thermogravimetric analyzer, the baseline drift of the thermogravimetric curve caused by buoyancy and convection and the convection caused by the temperature difference inside and outside the thermobalance will affect the accuracy of weighing

The packing is tight and the contact between the sample particles is good, which is conducive to heat conduction, but not conducive to gas diffusion

The filling is required to be thin and uniform, but the actual samples are concentrated and distributed at the bottom of the reaction vessel, and the distribution is uneven; during the sampling process, the reaction vessel needs to be removed, and after weighing the sample on an independent balance, wrap it with filter paper, etc. The sample is added to the reaction vessel, and the reaction vessel is placed on the support rod for the experiment. The various operations make the balance interfered by various uncertain factors, which reduces the accuracy of the balance.

In the ordinary experimental process, it is easy to lead to inaccurate experimental data, which affects the detection and analysis of samples.

As a result, the experimental data of thermogravimetric analysis cannot well explain the true characteristics of actual industrial raw materials, which has a negative impact on experimental research and industrial application reference

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