Zhejiang Hengyi Petrochemical Research Institute Co., Ltd.

Altenergy Power System, Inc.

Fei Shen

Songlin Wang

Shibiao Cheng

Han Wang

Xi Li

Xinping Zhang

Yuhao Luo

Dongming Zhou

Wenwei Li

Xuan Zhu

Guowei Miao

Xiaokang Hu

Zong Li

Yixuan He

Xiao Lu

Dejia Ma

Zhaobin Jiang

Zhimin Hu

A method and an apparatus for controlling a shutoff device, and a shutoff device. The method is applied to a processor of the shutoff device. The method includes: determining whether a heartbeat signal is received continuously during a first preset period; if so, controlling the N main switching transistors to be turned on, and determining whether the heartbeat signal is not received continuously during a second preset period; and if so, controlling the N main switching transistors to be turned off, and controlling the release circuit to be turned on to release a voltage on the bus. A release circuit is controlled to release voltage on the bus to the ground, thereby rapidly reducing the voltage on the bus, avoiding person danger and safety accidents caused by the long-term presence of the direct current high voltage on the bus, and improving the safety and reliability of a photovoltaic system.

Control method and apparatus for shut-off device and shut-off device

The present disclosure discloses a method for preparing caprolactam including: (1) contacting cyclohexanone oxime with a catalyst to carry out reaction in the presence of ethanol and under the condition of gas phase Beckmann rearrangement reaction of cyclohexanone oxime; (2) separating the reaction product obtained in step (1) to produce an ethanol solution of crude caprolactam, and then separating the ethanol solution of crude caprolactam to obtain ethanol and crude caprolactam; (3) removing impurities with boiling points lower than that of caprolactam in the crude caprolactam to obtain a light component removal product; (4) mixing the light component removal product with a crystallization solvent to carry out crystallization and solid-liquid separation to obtain a crystalline crystal; (5) subjecting the crystalline crystal to a hydrogenation reaction; wherein the crystallization solvent contains 0.1-2 wt % of ethanol.

Preparation method of caprolactam

A refining process includes steps of subjecting crude caprolactam to a first evaporative crystallization and a first solid-liquid separation to obtain a first caprolactam crystal and a first crystallization mother liquor; washing the first caprolactam crystal to obtain a second caprolactam crystal; optionally concentrating the first crystallization mother liquor to perform a second evaporative crystallization and a second solid-liquid separation to obtain a third caprolactam crystal and a second crystallization mother liquor; subjecting the third caprolactam crystal to a second washing to obtain a fourth caprolactam; optionally concentrating the second crystallization mother liquor to perform thermostatic crystallization, performing separation to obtain a fifth caprolactam crystal and a third crystallization mother liquor; washing the fifth caprolactam crystal to obtain a sixth caprolactam crystal; and subjecting the second caprolactam crystal to a hydrogenation reaction.

Refining process and refining system of caprolactam

Growing community of inventors

Zhejiang, China

Fei Shen