Central South University

Zoomlion Heavy Industry Science and Technology Co., Ltd

Hunan Zoomlion Special Vehicle Co., Ltd.

Shuai Wang

Hong Zhong

Guangjun Gao

Liang Wan

Jiaqian Wang

Peilin Li

Weiyuan Guan

Xiaoping Huang

Zhanfang Cao

Xin Ma

A method for preparing xanthate by a slurry method includes steps of: adding a mixture of dichloromethane and carbon disulfide as a reaction solvent in a slurry reactor, and then adding alcohol and caustic alkali to react with carbon disulfide under less than 1 atm to remove heat released by the reaction by evaporating the solvent; performing vacuum distillation after the reaction to remove the solvent and water, so as to obtain the xanthate; transporting the xanthate to a granulation equipment for granulating, and then drying in a drying equipment to obtain a product. The method is performed in a system formed by a reaction equipment, a solvent recovery equipment, the granulation equipment, and the drying equipment, wherein a main equipment of the reaction system is a slurry reactor. The method has advantages of high efficiency, low energy consumption, good safety, environmental friendliness, convenient operation and the like.

Method and system for preparing xanthate by slurry method

A reusable collision energy absorption device for a rail vehicle includes an impacted rod, a damping structure including a damping plug, a guide tube and a damping elastic element, a return structure including a return piston and an elastic return element, an outer tube having a tubular structure, and an interior partitioned into a front cavity and a rear cavity through a partition plate provided with a damping hole in the form of a through hole. A portion of the damping plug is in the damping hole when the damping plug is in an initial position, and the damping plug can move in a front-rear direction when the device is impacted. A gap between a radial thickest portion of the damping plug and the damping hole allows the fluid to circulate between the front cavity and the rear cavity.

Reusable collision energy absorption device for rail vehicle

The invention belongs to the field of mineral flotation collector materials, and particularly discloses a method for preparing thionocarbamate. In the preparation process, xanthate and 2-haloethanol are esterified to obtain O-alkyl-S-hydroxyethyl xanthate, and then O-alkyl-S-hydroxyethyl xanthate and fatty amine are reacted to obtain a mixture of thionocarbamate and 2-mercaptoethanol. The mixture of thionocarbamate and 2-mercaptoethanol is washed with alkali, and the oil phase and water phase are separated. The oil phase and water phase are thionocarbamate and 2-hydroxyethylthiolate, respectively, and 2-mercaptoethanol is obtained by washing with an acid. 2-alkylthioethanol is obtained by reacting 2-hydroxyethanethiolate with alkyl halide, and then with carbon disulfide and alkali to prepare O-alkylthioethyl xanthate. Thionocarbamate, 2-mercaptoethanol and O-alkylthioethyl xanthate prepared by this method possess high yield and high purity. The process is green and environmentally friendly, and is beneficial to the industrialization of co-production.

Method for preparing thionocarbamate and co-producing 2-mercaptoethanol or O-alkylthioethyl xanthate

Disclosed are a concrete distributing device and a control method, a control system and an electrical control system for composite motion of a boom thereof. The control method comprises the steps as follows: calculating the flow of a boom pump when an operating handle sends a command; according to the command sent by the operating handle, calculating theoretical demand flow of all actuating mechanisms of the boom and theoretical control signals of all electronic proportional control valves; comparing the total theoretical demand flow of the actuating mechanisms with the flow of the boom pump; providing the theoretical control signals to all the electronic proportional control valves when the flow of the boom pump is greater than or equal to the total theoretical demand flow of the actuating mechanisms, otherwise, providing actual control signals smaller than the theoretical control signals to all the electronic proportional control valves and reducing the movement speeds of all the actuating mechanisms proportionally. In this way, when undersaturation of system occurs to the composite motion of the boom, the movement speeds of all the actuating mechanisms are reduced proportionally independent of the load difference of the actuating mechanisms, thereby ensuring that the boom can move in a motion track expected by an operator.

Concrete distributing device and control method, control system and electrical control system for composite motion of boom thereof

Growing community of inventors

Changsha, China

Shuai Wang