Objective
Aim of the project is the reduction in energy consumption by 27 % for the grinding of cement.
The reduction will be achieved by usage of special grinding equipment such as a division head diaphragm with controllable material-flow and a certain type of shell-liner with a grooved face. In combination with an new selective separator of the third generation which also features particular design characteristics an existing ballmill made by SKET/ZAB will be improved in its grinding efficiency.
For the production of high-quality-cement with a fineness of 6000 cm2/g (Blaine) the finished product had to be free of coarse particles.L%
The installation has been completed in November 1992 so that commissioning started on 1. Dec. 1992.
With the results of two test runs in April 1993 a significant reduction in use of energy could be evaluated.
It was foreseen in the application for this THERMlE-project that a saving in energy of about 27 % should be reached.
According to the data of the test-runs a reduction of 28,2 % has been obtained.
This solution offered a based on the achieved spec. average energy consumption on 0,0082 TEP/t. cement by the improvement of the installation.
In general all major components of the grinding plant have performed well without any mechanical or electrical failure during the 1700 hours of operation since normal production started on 15 Dec. 1992.
Only one problem remained in the control of material-flow by the division head inside the mill.
Two steps of modification of the design and structure of the division head have already be carried out in order to improve the functionality of thediaphragm.
It can be foreseen from the present standpoint of view, that there is still some room for further optimization.
This might even led to higher reduction in the use of electrical energy for the grinding of cement.
In combination with the Thermie project a new dedusting equipment was installed which reduces the dust emission by 87%.
An existing ballmill made by SKET/ZAB of the former GDR will be equipped with modern grinding technology in order to improve grinding performance and to reduce energy consumption for the process. Inside the ballmill there will be installed a new division head diaphragm which features an adjustable mechanism to control material-flow from the primary to the secondary grinding compartment. Also a special grooved type of shell-liner will enhance grinding capability due to its larger face-area. Along with a new selective separator of the third generation the grinding process will need 27 % less electrical power. Altogether the project is unique because never before such parts have been combined on a ballmill made by SKET/ZAB. The three elements of modern grinding technology are characterized by the following features:
Division head diaphragm
It has an integrated material-flow mechanism which can be adopted at best to the specific grinding conditions. Also it has an higher permeabilityso that the mill venting can be improved, transporting fine ground particles from the first into the second grinding compartment but coarse particles will be hindered from entering the second compartment. Grooved shell-liner
The grooved shell-liner-plates inside the mill will enhance grinding capability of the ball-charge. The grooved face of the plates increases the area in which the grinding materials can be ground in contact between the balls and the plates. A certain pattern in which the plates are arranged also allows it to activate the ballcharge according to the development of the materials being ground.
Separator
The separator is one of the selective type of the third generation. It features a special touch-free sealing-system between the rotating separatorcage and the housing. This will improve the precipitation of very fine cement which will not contain any coarse particles to reach a fineness of 6000 cm2/g (Blaine). The special sealing has to be adjusted in accordance to the properties and the particle-size-distribution of the separator feed.
Programme(s)
Topic(s)
Call for proposal
Data not availableFunding Scheme
DEM - Demonstration contractsCoordinator
Germany