Integrated Process of Immediate One-Step Lime Precipitation, Atmospheric Carbonation, Constructed Wetlands, or Adsorption for Industrial Wastewater Treatment: A Review

Abstract

The transition from the linear economy paradigm to the circular economy in industrial wastewater treatment systems is on the global agenda. The search for new simple, eco-innovative, and low-cost processes for treating industrial wastewater, which can also be used by small and medium-sized industries, has been a constant challenge especially when environmental sustainability is considered. So, a new integrated industrial wastewater treatment system has been developed that includes the immediate one-step lime precipitation process (IOSLM) and atmospheric carbonation (AC), followed by constructed wetlands (CWs) or adsorption. The current review provides an overview of industrial wastewater treatment strategies for high- and low-biodegradable wastewater. A background on functionality, applicability, advantages and disadvantages, operating variables, removal mechanisms, main challenges, and recent advances are carried out for each process that makes up the IOSLM+AC+CW/adsorption integrated system. The prospects of the IOSLM+AC+CW/adsorption integrated system are also discussed. Not neglecting the improvements that still need to be made in the integrated treatment system as well as its application to various types of industrial wastewater, this review highlights that this treatment system is promising in industrial wastewater treatment and consequent by-product recovery. The IOSLM+AC integrated system showed that it can remove high amounts of organic matter, total suspended solids, oils and fats, phosphorus, and ammonium nitrogen from industrial effluents. On the other hand, constructed wetlands/adsorption can be alternatives for refining effluents still containing organic matter and nitrogen that were not possible to remove in the previous steps.

Reuse of Treated Slaughterhouse Wastewater from Immediate One-Step Lime Precipitation and Atmospheric Carbonation to Produce Aromatic Plants in Hydroponics

“…Raw SWW was treated by the IOSLM/AC sequence (Figure 2) according to the optimal conditions found by Madeira et al [9]. Briefly, raw SWW was treated by IOSLM which consisted of adding a hydrated lime solution (200 g L −1 ), under vigorous stirring, until reaching pH 12.…”

“…Subsequently, the effluent is subjected to the AC process to reduce the pH. The decrease in the pH of the effluent to around neutrality occurs through the reaction The IOSLM process' removals of COD, BOD, organic nitrogen, TSS, oils and fats, and turbidity are explained by the extensive formation of calcium carbonate and magnesium hydroxide precipitates formed at a high reaction pH with the addition of hydrated lime, which can act as a coagulant and drag impurities present in the effluent during sedimentation [9]. Furthermore, phosphorus can be removed in the form of calcium phosphate and octacalcium phosphate [34,35].…”

“…Subsequently, the effluent is subjected to the AC process to reduce the pH. The decrease in the pH of the effluent to around neutrality occurs through the reaction with atmospheric CO 2 [9,37]. While the effluent is neutralized, the ammonia present in the effluent is removed by volatilization until equilibrium is reached [38].…”

“…Therefore, it is necessary to rethink how SWW should be treated and then recovered. Recently, a low-cost and easy-to-apply pretreatment process composed of immediate one-step lime precipitation (IOSLM) and atmospheric carbonation (AC) has been developed to treat SWW [9]. High removals of organic matter, suspended solids, oils and fats, and nutrients were obtained, and the sludge obtained has potential recovery as a coagulant aid [10,11].…”