Jinan University

Guangdong Industry Polytechnic

Mei Li

Liang He

Jinwei Chen

Baiping Xu

Huiwen Yu

Wenliu Zhuang

Mengxi Wu

Chunlei Cheng

A co-rotating self-cleaning multi-screw extruder with a speed ratio of 2.5 and an extruding method therefor are disclosed. The screw mechanism includes a center screw and peripheral screws which rotate in the same direction. The peripheral screws are each of a double threaded structure, and the center screw is of a quintuple threaded structure. The rotation speed of the peripheral screws is 2.5 times that of the center screw, and the peripheral screws are always meshed with the center screw, whereas the adjacent peripheral screws are intermittently meshed with each other. The extruding method therefor is as follows: there is a periodically open space between adjacent peripheral screws, providing the periodical and intermittent mixing action, so that material from different thread grooves is mixed with each other. Meanwhile, the topological chaos action, by which the material is cut into two portions, is formed between the center screw and the peripheral screws, and the chaos mixing is caused by the random motion which is generated from the periodical changes of the channel, so that a periodical action of 'compression-expansion' is achieved. Furthermore, due to the tensile force field action caused by the differences in rotation speed between the center screw and the peripheral screws, the compression preheating and dispersion mixing of the material are achieved. The co-rotating self-cleaning multi-screw extruder effectively improves the efficiency of conveying and mixing of materials.

Co-rotating self-cleaning multi-screw extruder with speed ratio of 2.5 and extruding method therefor

The present disclosure provides an online monitoring and source apportionment method for atmospheric particles containing heavy metals, and belongs to the technical field of online quantification and source tracing of atmospheric particles containing heavy metals. The single particle aerosol mass spectrometer and X-ray fluorescence spectrometer are combined to quickly determine the concentration, time series, chemical compositions and mixing state of atmospheric particles containing heavy metals from both qualitative and quantitative perspectives. A heavy metal-containing particle mass concentration limit system is incorporated into the X-ray fluorescence spectrometer. Once the mass concentration of a particle containing heavy metals exceeds the standard, the aerosol mass spectrometer can immediately receive this alert through the information transmission system. The online source tracing system of aerosol mass spectrometer will start immediately after receiving the signal of the heavy metal exceeding the standard.

Real-time online monitoring and source apportionment method for atmospheric fine particles containing heavy metals

Growing community of inventors

Guangzhou, China

Mei Li