How to Improve the Conveying System in Gypsum Production Line?

by Ivy Z. Mining Equipment Sales

Gypsum board is a material made of gypsum as the main raw material. As one of the new lightweight planks that develop emphatically at present, it is a building material with lightweight, high strength, thinner thickness, convenient soil filling, sound insulation, heat insulation, and fire prevention.

Gypsum board has been widely used in interior partitions, wall cladding panels (instead of wall plastering), ceilings, sound-absorbing panels, and ground bases of various buildings such as residences, office buildings, shops, hotels, soil industry plants and various decorative boards.

The raw material for the production of gypsum board in the traditional gypsum board industry is calcium sulfate. There are two main sources of calcium sulfate: one is natural gypsum, which is gypsum stone, and the other is chemical gypsum, a by-product of the soil industry (mainly desulfurized gypsum, a by-product of the soil industry in coal-fired power plants).

Using desulfurized gypsum to produce gypsum board not only solves the problem of raw materials, but also solves the problem of sulfur dioxide air pollution in coal-fired power plants and the inability to store desulfurized gypsum. It not only avoids damage to farmland, but also absorbs and utilizes a large number of industries by-products, improves the ecological environment, and at the same time, also reduces the manufacturing cost of gypsum board.

How the conveying and feeding system is designed in the gypsum production line?

The desulphurized gypsum is transported to the clinker bin after calcined, grinding and pneumatic conveying, and then to the blender through the clinker conveying system. The clinker conveying system is mainly composed of a dividing wheel, screw conveyor, bucket elevator, feeding screw conveyor, return screw conveyor, metering electronic belt scale, mixing screw conveyor, dust collector, etc.

What are the problems in actual production?

The project uses 100% power plant waste desulfurized gypsum as the main production raw material. During the trial production process, it was found that the fluidity of calcined gypsum powder obtained after calcining desulfurized gypsum was greatly increased compared with that of natural gypsum calcined. The existing equipment of the clinker conveying system cannot meet the production needs, which prevents normal production.

A stable dosage of plaster of Paris is a key factor for producing qualified products. The existing gypsum plaster powder used in the molding system comes from the intermediate storage. According to the change of the material properties, the loading volume of the intermediate storage grid wheel is unstable, which directly affects the dosing of the electronic belt scale, as well as the product quality and percent of pass.

Solution

Aiming at the situation that the conveying volume of plaster powder cannot be controlled stably, the following improvements are made to the clinker conveying system and the return system.

Add a level gauge to the screw conveyor, string its signal to PLC automatic control, and automatically control and adjust the feeding amount through the program according to the actual situation of production, so that the amount of plaster is basically constant to ensure that a certain amount of desulfurized gypsum is returned to the intermediate warehouse by the return system, so as to stabilize the conveying quantity of gypsum powder and effectively improve the qualified rate and quality of products.
Adjust the inclination angle of the screw conveyor to 150, which effectively avoids the phenomenon of belt scale feeding and ensures the amount of plaster of Paris powder;
The screw conveyor and the electronic belt scale adopt synchronous speed regulation, and the control range of the synchronous speed regulation is precisely adjusted by adding the analog signal of the detection equipment, so that the conveying amount of the plaster powder is basically constant.
The end of the electronic belt scale is installed with a material receiving box, which plays a buffering role in the conveying process of gypsum powder, and can play the role of a small intermediate storehouse, ensuring a sufficient supply of plaster of Paris powder during the synchronous speed regulation process;
Carry out physical calibration of the electronic belt scale and continue to correct the coefficient to control the feeding deviation within 5%.
Add return testing equipment in the return system to measure the return amount of gypsum powder. At the same time, set a high limit and a low limit alarm to achieve the stability of the system transmission amount through frequency conversion control of the conveying equipment.