A Review on Valorizing Poultry Wastes: Eco-Friendly and Sustainable Solutions

The global poultry industry has experienced significant growth, leading to a noticeable increase in waste generation, including faecal excreta, feed spillage, feathers, hatchery effluent, animal mortality, and bedding material. Conventional disposal techniques such as burning, incineration, burial, and landfilling have adverse effects on the environment and human health. These disposal methods pollute the air, water, and soil by increasing greenhouse gas emissions and facilitating disease transmission, including cholera, typhoid, malaria, filaria, and dengue fever. Thus, it is imperative to use sustainable and eco-friendly waste management methods, such as composting, anaerobic digestion, pyrolysis and gasification, rendering, microbial and enzymatic treatment, and vermicomposting, which help recycle poultry wastes by converting them into useful products such as organic fertilizer, animal feed, biogas, drugs, and cosmetics. The objective of this literature review is to provide an overview of the scientific literature on sustainable and environmentally acceptable methods for valorizing poultry waste into valuable products. Valorizing poultry wastes can reduce environmental and health impacts while producing valuable products used as animal feed and industry raw material. Composting poultry waste can be used to create organic fertilizer for soil amendment. Anaerobic digestion, pyrolysis, and gasification are techniques that can generate biogas, syngas, and biochar as energy and feedstock, such as feather meal, meat and bone meal, and tallow from poultry waste. Through rendering, fats and proteins can be recovered from abattoir wastes and used in the soap, cosmetics, and pharmaceutical sectors, as well as in animal feed. Vermicomposting is another poultry-waste valorisation method that uses earthworms to decompose organic waste and produce high-quality compost. The aforementioned methods for valorizing poultry waste contribute to a circular economy by recycling waste through eco-friendly and sustainable processes, though their applications are limited by elevated capital and energy costs, scalability challenges, technical complexity, and sensitivity to waste variability. Therefore, it is recommended to promote the adoption of poultry waste valorization methods among poultry producers and enhance sustainability in the poultry sector by minimizing pollution caused by poultry waste and recycling it into valuable products.