This book is a compilation of process, technologies and value added products such as high value biochemicals and biofuels produced from different waste biorefineries. The book is sectioned into four categories providing a comprehensive outlook about zero waste biorefinery and technologies associated with it. The emerging technologies that potentially put back the lignocellulosic waste, municipal solid waste and food waste into intrinsic recycling for production of high value biochemicals and bioenergy, along with associated challenges and opportunities are also included. The content also focuses on algal biorefineries leading to sustainable circular economy through production of broad spectrum of bioactive compounds, bioethanol, biobutanol, biohydrogen, biodiesel through integrated biorefinery approach. The volume also includes chapters on conversion technologies and mathematical models applied for process optimization. A sound foundation about the underlying principles of biorefineries and a up-to-date state-of-the-art based overview on the latest advances in terms of scientific knowledge, techno-economic developments and life cycle assessment methodologies of integrated waste biorefinery is provided. This volume will be of great interest to professionals, post-graduate students and policy makers involved in waste management, biorefineries, circular economy and sustainable development.