What is the potential for utilizing the resources in sludge?

Abstract

The successful strategy for water protection by biological wastewater treatment results in a sludge production of about 20 to 40 kg dry matter per population equivalent and year. In the context of regional material fluxes, sewage sludge has a low resource potential and a low pollution potential despite the fact that it can be characterised as a sink, concentrating wastewater compounds. The mass flow of nutrients (N, P) in the sewage sludge is comparatively small as compared to the losses of nutrients in agriculture. The most valuable element in the sludge is phosphorus, as the availability of phosphorus for the production of low-cost mineral fertiliser is limited. The most economical means of P-recycling is agricultural sludge application, which can also be seen as the option with the lowest loss of all valuable compounds of the sludge, and the lowest increase of entropy. The reliability of this disposal route for the treatment plant operator depends on several major pre-requisites: * reliability in regard to hygiene * reliability in regard to long-term soil protection public acceptance (politicians, media) * acceptance by all parties involved in sludge application and its consequences (farmers, farmer unions, land owners, food industry, food trade, retailers, consumers, consumer associations, NGOs, etc.) Only the first two prerequisites can be based on scientific research and risk assessment. As a consequence, only for these two aspects can quality criteria and adequate procedures be developed and introduced into a legal framework and quality assurance procedures. The latter two pre-requisites must be addressed in terms of sociology, psychology and political science and have a strong educational aspect.

Sustainable groundwater management in Lagos, Nigeria: the regulatory framework

“…It notes the excessive waste in water use, and emphasizes water savings especially within industrial and domestic water use, pointing out that recycling can reduce the consumption of many industrial consumers by 50% or more, with the additional benefit of reduced pollution. It also observes that an average of 36% of the water produced by urban water utilities in developing countries is "unaccounted for", an 135 Ibid.…”

“…From these options, the engineered landfill appears the most feasible, being that it has waste compaction which is already in place in Lagos, and will incorporate leachate containment that keeps groundwater safe from contamination. However, it is advisable that Lagos begins to think in serious terms of making some significant investment in a safer method of waste management 135 in order to safeguard the health of its residents. Such investment is likely to help the city to save money in the long term by reducing the financial burden that sick people impose on the healthcare system, by reducing mortality and extending lifespans, and by reducing the overall strain on the economy.…”

Value-Added Products Derived from Waste Activated Sludge: A Biorefinery Perspective

“…Sodium palmitate is another detergent that, unlike SDS, can be readily removed by organic solvent extraction at low pH. Combined with alkali (e.g., 0.15 mM NaOH), sodium palmitate can achieve up to 15 mg protein/mL from WAS with 5% solids solubilised [20].…”

Effect of Ozonation and Sonication on Biochemical Methane Potential of Biosludge from Textile Mill Effluent

“…It has been known that the domestic and industrial wastewater treatment systems will produce a large amount of biosludge, i.e., about 20-40 kg of dry sludge for every population served per annum (Kroiss 2004). The conventional methods of sludge treatment, such as landfill, incineration, and composting are still having some limitations.…”