Valorisation of wastewater from two-phase olive oil extraction in fired clay brick production

• Published in: Journal of hazardous materials 2009-09, Vol.169 (1), p.271-278
• Main Authors: de la Casa, José A., Lorite, Miguel, Jiménez, Juan, Castro, Eulogio
• Format: Article
• Language: English
• Subjects: Aluminum Silicates; Applied sciences; Biological and medical sciences; Ceramic building materials; Construction Materials; Exact sciences and technology; Food engineering; Food industries; Fundamental and applied biological sciences. Psychology; General aspects; General purification processes; Industrial Waste - prevention & control; Olea; Olive mill wastewater; Olive Oil; Physical properties; Plant Oils; Pollution; Two-phase olive oil extraction; Waste Disposal, Fluid - methods; Wastewaters; Water Pollutants; Water treatment and pollution
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2009.03.095

Wastewater issued from oil-washing stage (OWW) in the two-phase olive oil extraction method was used to replace fresh water in clay brick manufacture. The extrusion trials were performed with one of the ceramic bodies currently being used in a local brick factory for red facing bricks (RB) production. Fresh water or OWW was added to a final consistency of 2.4 kg/cm 2, the same value as used at industrial scale for this kind of clay mixture. Comparative results of technological properties of facing bricks are presented. Results show that the products obtained with olive oil wastewater are comparable to traditional ones in terms of extrusion performance and technological properties of end products. Even dry-bending strength of the body formed by wastewater improves by 33% compared to fresh water body. In addition, heating requirements can be reduced in the range 2.4–7.3% depending on the final product. This application can alleviate environmental impacts from the olive oil extraction industry and, at the same time, result in economic savings for the brick manufacturing industry.