A hydrate-based zero liquid discharge method for high-concentration organic wastewater: resource recovery and water reclamation

Abstract High-concentration organic wastewater has become a great challenge for wastewater treatment due to its toxicity and non-biodegradability. Traditional water treatment methods focus on removing or destroying organic pollutants rather than considering the high-concentration organic wastewater as a resource. As an ambitious sustainability goal, resource recovery from wastewater to achieve zero liquid discharge (ZLD) has attracted widespread attention. Here, a hydrate-based method is proposed to treat textile wastewater to facilitate the reuse of dyes and enhance water reclamation. The mechanism of interaction between hydrate and organic pollutants was invested. The results show that organic pollutants are rejected from the growing hydrate lattice and concentrated in the residual solution. This method can achieve a max removal efficiency of 93.6% and a water production rate of 80%. In the range of 0–2000 mg/L, the concentration of organic pollutants does not affect the removal effect and water production rate. The concentrated dye can be reused again. The proposed method exhibits potential for recovering resource and clean water from wastewater while achieving ZLD.