Mercury removal from contaminated mud coming from chlor-alkali plant

P. Massacci, V. Modesti, L. Piga*

Dipartimento di Ingegneria Chimica, dei Materiali, delle Materie Prime e Metallurgia,
Università di Roma “La Sapienza”, Roma, Italy

Received 7 May 2003; accepted 15 March 2004


The paper considers the problem of decontamination of mud coming from a chlor-alkali plant. The mud heavily polluted by mercury has been analysed in order to ascertain the solid phases and the modalities of mercury association. Taking into consideration the characteristics of mercury in respect to the inert association of solid components of the mud, a laboratory-scale thermal-based process has been developed. The volatile products coming from thermal treatment have been captured in suitable traps in order to avoid any diffusion of the metal into the atmosphere, thus ensuring safe environmental conditions. Material balance ascertained before and after the treatment process indicates success of the operation which provides a silt and sand product containing mercury at a level lower than that fixed for acceptance of the material for reuse in land restoration.

Keywords: Mercury; Mud pollution; Thermal treatment

* Corresponding author
   E-mail : Luigi.Piga@uniroma1.it