Sludge disposal schemes

Figure 7. Sludge disposal schemes for a single scrubber system...

The availability of the analytes for uptake by plants, for transport through the soil, and for dissolution into water can be estimated from a well-studied speciation scheme. Risk assessment for disposal of wastes in landfills or for land disposal of dredge spoils or sewage sludges requires knowledge not only of the total metal content but also of the content in each separate fraction to begin to understand how the metals will act in the environment. Table 5.7 summarizes the methods available for speciation of metals in samples. 

Anon. Paper sludge—from a disposal problem into a valuable product. DTTs Environmental Management Options Scheme. Project Information Brochure No 3, 1994a. 

Equalisation tank and its hold-up volume should be adequate for storing effluent generated in 24 h at least so that shock loads are taken of Process flow scheme for the treatment in general giving proposed pH adjustment, aerobic or anaerobic process employed, aeration unit, active carbon unit, sludge disposal luiit. 

At CEN level, EN14987 was published in 2006 Plastics - Evaluation of disposability in wastewater treatment plants - Test scheme for final acceptance and specifications. The pass level for biodegradation is 90%, which must be reached within a maximum of 56 days. Aquatic biodegradation tests must be used, with sludge as the only inoculum... 

---