The poultry industry has met more than one-third of the human demand for meat and all the demand for eggs during the past several decades, and it has also been recognized as a very efficient sector in the livestock industry. However, increasing poultry production has also led to the massive generation of various poultry wastes, which are a great threat to climate change, environmental safety, and human health. Traditionally, landfilling and burning are the most frequently used techniques for treating poultry waste. With rich contents of organic matter, nutrients, and keratin, poultry waste can be applied to produce value-added products that can be used in many sectors by using a variety of emerging technological processes. Considering the massive generation, profound environmental pollution, and wide range of applications of poultry waste, this paper categorizes poultry waste as litter and manure waste, feather waste, mortality waste, abattoir waste, and hatchery waste. This paper also reviews modeling and simulation studies on poultry waste-to-wealth, and six current or emerging technological processes for poultry waste-to-wealth are described: anaerobic digestion, pyrolysis, gasification, hydrolysis, enzymatic treatment, and microbial conversion. Finally, the economic, environmental, and social impacts of the sector of poultry waste-to-wealth are discussed. For further research, we suggest a focus on the poultry waste-to-wealth projects in different regions, the behavior strategy of different stakeholders, and policymaking for the commercialized application of poultry waste-to-wealth technologies.
