Twittern

Gypsum reduced

• Installation plan for the Triple A wet jigging...

• Experimental rig for testing the jigging process...

•  View inside the jig bed

•  Light material discharge onto the dewatering...

•  Particle size distributions of the starting...

•  Building material from the bath cubicles

• Diagram showing the sequence for the sample...

• Mass balance calculated as average values from...

• Changes in the levels of concrete in the product...

• Changes in the levels of gypsum in the product...

• Changes in the levels of gypsum in the product...

• Decrease in the amount of product generated and...

• Changes in the levels of gypsum and brick in the...

• Mass distribution of the bulk densities of the...

• Changes in the levels of concrete and gypsum due...

• Changes in the levels of concrete and gypsum due...

• Changes in the particle size distributions of...

• Summarized comparison of the levels of gypsum in...

• Summarized comparison of the levels of concrete...

• Sampling of the material

• Wet jigging machine during the experimental...

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• Summarized comparison of the product bulk...

• Summarized comparison of the average particle...

• Summarized representation of the product yield...

Summary: Part 1 of the following article – published in AT 6/2010, p. 34-43 – discussed the structural implications of gypsum constituents in recycled concrete. The authors explain the possibilities available in mineral processing for the removal of this building material in the reclaiming of concrete rubble on the basis of a series of gypsum removal tests using jigs. Evaluation of the test results clearly shows an improvement in the quality of the recycled building material, which, thanks to the lower gypsum content, meets environmental and structural requirements and can easily be made suitable for further use.

4.2 Procedure for removing gypsum from recycled

­building materials during the jigging trials

The Triple A wet jigging machine together with all the necessary accessories and supply units was installed and commissioned at the Erfurt municipal works at the building waste recycling centre in Erfurt-Schwerborn. Fig. 8 shows the structure of the plant that consists of the actual wet jigging machine, a settling container, a pump sump, a dewatering screen and a Linatex 80 pump. The jigging machine, including the peripheral equipment and some details, is shown in Fig. 9 a–c. At full...