Alternative treatments for footwear industry liquid effluents. Part 1 Classic approach

• Type: Article in International Scientific Journal
• Date: 2002

Authors

M. J. Ferreira (Author) Other; M. F. Almeida (Author) FEUP; S. Pinho (Author) FEUP; A. Neves (Author) Other

Journal

Title: Journal of the Society of Leather Technologies and Chemists

Vol. 86 No. 3

Pages: 96-100

ISSN: 0144-0322

Publisher: Society of Leather Technologists and Chemists

Indexing

ISI Web of Science

Scopus

Scientific classification

FOS: Engineering and technology > Other engineering and technologies

CORDIS: Technological sciences

Other information

Resumo (PT): A indústria do calçado gera pequenas quantidades de efluentes líquidos não biodegradáveis devido a pigmentos, ácidos orgânicos e solventes. Uma aternativa de tratamento testado é a coagulação/floculação usando cal, sulfato de alumínio, cloreto férrico e sulfato férrico. Os resultados são 80-90% de redução na CQO e CBO5. Contudo o efluente não tem condições de descarga e exige uma etapa de polimento. Usando carvão activado as quantidades exigidas são muito elevadas.

Abstract (EN): The footwear industry generates small volumes of non-biodegradable liquido effluents from finishing operations which have a high organic load, mainly due to pigments, organic acids and organic solvents. In consequence, these effluents must be treated to accomplish regulatory requirements before discharge. One of the treatment alternatives is coagulation/flocculation, a well-known treatment for removing fine particles and colloids. Tests carried out using lime, aluminum sulphate, ferric chloride and ferric sulphate as coagulants gave chemical oxygen demand (COD) and 5-day biochemical oxygen demand (BOD5) removals over 80-90%. However, despite this efficiency, some of the effluent characteristics are still higher than those imposed for discharge to surface waters, land or sewage systems. A polishing step using activated carbon adsorption is then required to permit the discharge to sewage systems, but the quantities of adsorbent required casts some doubt on the feasibility of the process.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 5