Harbour sludge

Witt, J., Schroeder, A., Knust, R. andAmtz, W.E. (2004). The impact of harbour sludge disposal on benthic macrofauna communities in the Weser estuary. Helgol. Mar. Res. 58 117-128. 

APACA CERAFOAM Pellets Harbour Sludge Utilisation... 

Besselink, H.T., E.M.T.E. Flipsen, M.L. Eggens, A.D. Vethaak, J.H. Koeman and A. Brouwer. Alterations in plasma and hepatic retinoid levels in flounder (Platichthys flesus) after chronic exposure to harbour sludge in a mesocosm study. Aquat. Toxicol. 42 271-285, 1998. 

In principle, the chemical stability of harbour sludge deposits, such as at Rotterdam and Hamburg (Fig. 10.10), is based on the low solubility of metal sulphides as well. The major difference is less mechanical stability of these structures compared with the deep anoxic marine basins, such as the Black Sea (many fjords provide similar conditions). Compaction and erosion are the problems at the man-made disposal sites. 

Secondary sources of PCDD/PCDFs, their reservoirs, are those matrices where they are already present, either in the environment or as products. Product reservoirs include PCP-treated wood, PCB-containing transformers and sewage sludge, compost and liquid manure, which can be used as fertilizers in agriculture and gardens. Reservoirs in the environment are, for example, landfills and waste dumps, contaminated soils (mainly from former chemical production or handling sites), and contaminated sediments (especially in harbours and rivers with industries discharging directly to the waterways). 

Figure 7-3 Schematic View of the Hydrocyclone and Elutriator Applied for Sludge Classification in Hamburg Harbour (Left). Hass Balance and Distribution of Heavy Metals (Right). After Hilligardt et al. (1986). TS = Dry Material.

With respect to the more problematic dumping activities it was decided by the Definitive Policy Plan of the Netherlands (1982) that of the dredged sludge from Rotterdam harbour only class 1 material from the western harbour area, which is primarily of marine origin, is permitted for disposal in the sea at the Loswal Noord site (approx. 13 million m per year). 

Scales P.J., Dixon D.R., Harbour P.J. and Stickland A.D., 2004. The fundamentals of waste-water sludge characterization and filtration. Water Sci. TechnoL, 49, 67-72. 

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