Recycling of waste-based materials in the clay brick industry
In research reports and papers, immense know-how on the recycling of waste is documented. Very little of this know-how, however, has found its way into an “industrial” production process. The paper describes possibilities for lowering raw material costs in the clay brick industry with the optimized utilization of waste materials – with the same or improved brick quality.
1 General
It is important to distinguish between “additions” to the clay body (such as, for example, sawdust or paper sludge) and “substitutions” (such as, for example, sewage sludge, fly ash or treated aluminium salt slag), which replace a part of the original clay body. The distinction between “addition” and “substitution” for extraneous materials is not always straightforward or easy.
An addition may be considered to be any substance added to the original clay body which does not exhibit any clay-like properties itself and is only used to effect pore formation or increase green strength. In...
