Enhancing anaerobic digestion using free nitrous acid: Identifying the optimal pre-treatment condition in continuous operation.

Free Nitrous Acid (FNA) pre-treatment is a promising technology demonstrated effective in improving waste activated sludge degradability and anaerobic digestion (AD) performance. Pre-treatment conditions including FNA concentration and treatment duration determine operational and capital cost of full-scale implementation, which have not been studied in long-term experiments. The knowledge of FNA pre-treatment conditions improving the AD performance is urgently required to determine suitable conditions for the technology implementation.

The origin of waste activated sludge affects the enhancement of anaerobic digestion by free nitrous acid pre-treatment.

Anaerobic digestion is a common stabilization method for treating primary sludge (PS) and waste activated sludge (WAS). However, its application is often limited by the degradation of WAS. Recent studies have demonstrated FNA to be an effective pre-treatment for enhancing WAS degradability, while having limited effect on PS degradability.

An integrated strategy to enhance performance of anaerobic digestion of waste activated sludge.

Anaerobic digestion (AD) is an essential process in wastewater treatment plants as it can reduce the amount of waste activated sludge (WAS) for disposal, and also enables the recovery of bioenergy (i.e. methane).

Organizational Wellness Program Implementation and Evaluation: A Holistic Approach to Improve the Wellbeing of Middle Managers.

: Employee wellness programs can provide benefits to institutions as well as employees and their families. Despite the attempts of some organizations to implement programs that take a holistic approach to improve physical, mental, and social wellness, the most common programs are exclusively comprised of physical and nutritional components. In this study, we implemented a wellness program intervention, including training using a holistic approach to improve the wellbeing of middle managers in several multinational organizations.