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Biosolids, the residual solids from wastewater treatment operations and once considered a waste product by the industry, are now becoming increasingly recognised as a multifunctional resource with growing opportunities for marketable use. This shift in attitude towards biosolids management is spurred on by increasing volatility in energy, fertilizer and commodity markets as well as moves by the global community towards mitigating global warming and the effects of climate change. This chapter will provide an overview of current global biosolids practices (paired with a number of Australian examples) as well as discuss potential future uses of biosolids. Additionally, present and future risks and opportunities of biosolids use are highlighted, including potential policy implications.

The global population explosion and the accompanying industrialisation have resulted, on the one hand in an increase in wastewater volumes and an almost innumerable list of constituents, and conversely, in an increasing shortage of water resources and basic food supplies, at least in some regions of the world. Current technologies enable almost all constituents to be eliminated from wastewater assuming the necessary financial resources are available, but appreciable quantities of sludge are produced. However, this handicap can be turned to advantage: sludge, when transformed into biosolids, is an ideal soil conditioner and fertilizer in agriculture. Thus the supposed threat of increasing waste can be transformed into a bonanza ‐ if operationally efficient logistics, administration and cost management systems are in place. Outlines current wastewater treatment practice in Germany, including the applicable directives and guidelines.

The purpose of this paper is to minimize environmental problems related to raw poultry manure application by stabilizing its nutrient and organic matter (OM) content. This can be achieved by prior digestion before its application to agricultural soils.

In the present study, changes in physicochemical and microbial properties of poultry litter were studied in order to evaluate the suitability of using the digested (stabilized) product for soil amendment. The poultry litter was digested in autothermal thermophilic aerobic digestor (ATAD) where organic solids were degraded and the heat released during the microbial degradation was used to maintain the thermophilic temperatures ( < 50ºC) at a hydraulic retention time of about 3 d.

Results of this study showed that the poultry litter undergoes physicochemical and microbial changes similar to other digestion systems; these changes include self-heating, relative increase in Cu, Zn, Fe, Mn, P, K and NO₃-N and decrease in microbial population numbers, C, OM and NH₄-N contents.

ATAD is an effective method for the conversion of poultry litter into organic fertilizer, which can be readily applied to the agriculture land. ATAD is an eco-friendly, cost effective method which also reduces the length of stabilization.

Describes field experiments to determine the effects of previous organic waste composts, using different types and application rates, on sunflower yield. Oil, carbohydrates and metal content were evaluated. Experiments were conducted in the Nuclear Research Centre Farm, in sandy, infertile soil. Results show a remarkable increase in dry matter and seed yields, due to previous single compost additions. A mixture of water hyacinth and biosolid compost showed an improvement. The results of this research indicate that application of organic waste composts is a feasible and valuable recycling method in sandy desert soils.

The purpose of this paper covers a perspective as related to sustainable development of natural resources with a focus on application of biotechnology in waste management.

The paper presents an overall view of industrial waste management practices as pertaining to substantiality of resources with emphasis on biodegradation of industrial pollutants. Methodologies employing biotechnology and striving towards the goal of sustainable development/production are discussed in this regard and particular attention is given to: regulatory consideration and trends; characterization of toxics for resource reuse; ecotoxicological assessment evaluations; treatment trends and innovative techniques, residual management.

Biotechnology is an important component needed to successfully achieve the goal of sustainability. “Value‐added” products from by‐products/waste and novel technologies employing biotechnical principles represent areas where significant opportunities exist.

The approach described here not only applies to water resource management but also includes multi‐media and multi‐disciplinary consideration.

The information presented herein hopefully will stimulate discussion and act as a catalyst for future direction. It perhaps may also serve as a point of reference for future evaluations of accomplishment.