Remediation and management techniques for industrial dairy wastewater and sludge: a review

Milk-based products are essential to the human diet, with India contributing 23% of global milk production. Dairy industries generate large amounts of waste, including solid and liquid waste, which are treated using wetland, biological, and physico-chemical methods. In India, dairy sludge is effectively managed by converting it into fertilizers. If industrial solid and liquid dairy waste is not managed correctly, it will increase pollution and harm biodiversity. If the sludge is properly managed, there is potential to transform it into various value-added products, including biofuels, biomass, biofertilizers, bricks, struvite, fertilizer, etc. Consequently, this technical review's focal topic includes information on dairy operations' wastewater treatment methods, the viability of microalgal cultures in wastewater, dairy sludge management, the range of biological product recovery, and its impact on the environment.