Hunan Sany Intelligent Control Equipment Co., Ltd.

Sany Heavy Industry Co., Ltd.

Central South University

Dong Li

Xiaogang Yi

Zuoliang Zhang

Runze Xu

Zhekui Quan

Xueyi Guo

Qinghua Tian

Provided is a method for catalytically reducing selenium. Hydrogen peroxide is used as a catalyst, and a reducer is added to a hexavalent-selenium-containing solution for reaction so as to reduce the selenium to elemental selenium, wherein the standard oxidation-reduction potential of the reducer is lower than the standard oxidation-reduction potential of the conversion of the hexavalent selenium to elemental selenium. The present method can further reduce a hexavalent-selenium element-containing selenic acid or selenate solution to an elemental selenium product in one step. In the present method, the hydrogen peroxide effectively lowers the descending speed of the reduction potential of the solution while having a catalytic effect, so that the reduction reaction process is carried out gently, thereby effectively preventing the selenium in the solution from overreducing to generate negatively bivalent selenium ions or compounds thereof, and solving problems such as a low recovery rate caused by selenium overreduction.

Method for catalytically reducing selenium

In one aspect of the disclosure, a cylinder-driven lifting mechanism of a compaction machine includes a cylinder having a first end and a second end, a fixed pulley set, a movable pulley set, a rope having a head end, and a tail end configured to connect a compaction hammer. The first end of the cylinder is connected to a vehicle body of the compaction machine and the second end of the cylinder is connected to the movable pulley set. The rope is wound on the fixed pulley set and the movable pulley set and is then connected to the compaction hammer. When the cylinder performs extension and refraction movement, the movable pulley set moves with the cylinder, the distance between the movable pulley set and the fixed pulley set increases or decreases, and the compaction hammer connected to the tail end of the rope is lifted up or dropped respectively.

Cylinder-driven lifting mechanism of compaction machine and compaction machine

The present invention provides a boom system, comprising a plurality of joint arms sequentially hinged through a horizontal hinge shaft, and further comprising: mounting two length sensors on each joint arm, wherein one length sensor measures the length of a corresponding joint arm after deformation, and the other length sensor measures the length between it and the distal end of the corresponding joint arm, and there is a preset distance between the two length sensors; mounting a dip angle sensor on each joint arm, and obtaining the angle between the connection line between the two length sensors and a reference plane; a processor which obtains boom system distal end position parameters according to the detection results of the dip angle sensor and the length sensors. The boom system according to the present invention, for a single joint arm, uses a single dip angle sensor and double draw line coders to obtain the distal end position parameters of the joint arm, and can more accurately obtain the boom system distal end position parameters. The present invention also provides an engineering machinery and a boom system distal end position parameter obtaining method.

Boom system, engineering machinery, and a method for acquiring boom system distal end position parameter

Growing community of inventors

Changsha, China

Dong Li