The slag powder is used to the concrete projects, such as projects involving in roads and bridges, which have higher requirements for bending strength. Meanwhile, the slag powder also suits to make concrete with high strength and high performance .The two advantages following of slag powder make it having great superiority in the big scale concrete projects, underground concrete projects and sea concrete projects.
Meng electricity cement plant took the opportunity promptly and invested and established a production line of slag powder with annual capacity of 60,0000t. Xinxiang Great Wall Machinery Co., Ltd has built the production line. The project has used the most advanced vertical mill system up to now. Different with the technology used in the conventional slag powder vertical mill system in the market, the Great Wall Machinery has innovated many new technology which ensure that the whole slag powder production can operation stably with high capacity, high efficiency ,low carbon.
1.Separation of dry material and wet material.
The slag and scrap (outside cycle) and wet slag will be put into the mill separately. The wet slag will be put into the mill by spiral reamer and the scrap with iron removal will be sent to vertical mill through rotary feeder.
When the dry powder of vertical mill scrap meets the wet slag, the weak water chemical reaction happens which leads to caking. That is because the slag itself has weak hydraulic. Therefore the usual mixture scheme of feeding material will lead to hardening of spiral reamer .The hardening will reduce transportation ability of reamer, and even will break the reamer.
2.The outside cycle using bury scraping machine and hauling engine and pipe iron remover combination.
Because the waster will always stay in the shell, using bury scraping machine and hauling engine and pipe iron remover combination to convey the outside waster from vertical mill can avoid overflow of waster and powder, which can improve the surrounding environment of vertical mill. For traditional belt conveyor and hanging iron remover and hauling engine and hauling engine combination, the air flow caused by the waster from the belt conveyor and the operation of hanging iron remover will lead to much floating dust and bad environment.
3.Set up steady flow storehouse ( middle storehouse).
Set up slag steady flow warehouse and make it near to the vertical mill ( located in the waster frame) .The slag measured by the belt scale under the slag steady flow warehouse will fell to a short belt, and the belt will convey the slag to spiral reamer for grinding.
Setting up the steady flow warehouse can make the material feeding of vertical mill more balance and the vertical mill will work more stable.
4.The waster material will be send to the vertical mill going through the outside warehouse.
The discharged waster will be discharged to waste warehouse to store under material framework by slide pipe when vertical mill stop work. The scale is installed under outside warehouse. The powder weighed by scale will be fed in vertical mill when starting vertical mill again.
5.Set the dust collector on the chute transportation corridor.
Setting a dust collector on the chute gallery between the powder collector and the finished products hauling machine can make the chute and hauling machine always work in a negative pressure condition ,which can stop the dust from overflowing caused by badly shell seal.
6.Using two gate valve to replace 3-way valve which has a high failure rate.
7.The large pieces of slag will be crushed again and again.
The large pieces of slag screened by rotary screen will go into the crusher machine for crushing and the fine particles after crushing together with the qualified fine particles will be sent to middle warehouse for grinding again. The slags are used 100 percent after realizing the feeding of loading machine.
8.Add the iron choosing machine to make a better separation effect of slag and iron.
9.Other creative industrial technique
Around the foundation of the vertical mill, besides of the submerged scraping machine, other pipes like (hydraulic pipe, lubricating oil pipe, cable threading pipe) are put in the trench or buried in the foundation of vertical mill).
Set a supporting at the expansion joint of the dust collector’ air inlet and air outlet, in order to stop the pipe from sinking after several years.
The concrete platform is built in the finished product warehouse 5.300 which is used for the .repairing of electric ball machine. A daylighting window is installed on the silo wall.
Bulk machine with optimization design can avoid the powder spray outside because of the positive pressure when the bulk car is fully filled.
Set chimney at the centrifugal fan of small dust collector to reduce the noise.