Nitrogen Recovery from Wastewater: Possibilities, Competition with Other Resources, and Adaptation Pathways

Abstract

Due to increased food production, the demand for nitrogen and phosphorus as fertilizers grows. Nitrogen-based fertilizers are produced with the Haber–Bosch process through the industrial fixation of N2 into ammonia. Through wastewater treatment, the nitrogen is finally released back to the atmosphere as N2 gas. This nitrogen cycle is characterized by drawbacks. The energy requirement is high, and in the wastewater treatment, nitrogen is mainly converted to N2 gas and lost to the atmosphere. In this study, technologies for nitrogen recovery from wastewater were selected based on four criteria: sustainability (energy use and N2O emissions), the potential to recover nitrogen in an applicable form, the maturity of the technology, and the nitrogen concentration that can be handled by the technology. As in wastewater treatment, the focus is also on the recovery of other resources; the interactions of nitrogen recovery with biogas production, phosphorus recovery, and cellulose recovery were examined. The mutual interference of the several nitrogen recovery technologies was studied using adaptive policy making. The most promising mature technologies that can be incorporated into existing wastewater treatment plants include struvite precipitation, the treatment of digester reject water by air stripping, vacuum membrane filtration, hydrophobic membrane filtration, and treatment of air from thermal sludge drying, resulting respectively in 1.1%, 24%, 75%, 75%, and 2.1% nitrogen recovery for the specific case wastewater treatment plant Amsterdam-West. The effects on sustainability were limited. Higher nitrogen recovery (60%) could be realized by separate urine collection, but this requires a completely new infrastructure for wastewater collection and treatment. It was concluded that different technologies in parallel are required to reach sustainable solutions. Nitrogen recovery does not interfere with the recovery of the other resources. An adaptation pathways map is a good tool to take into account new developments, uncertainties, and different ambitions when choosing technologies for nitrogen recovery.

The Adsorption of Ammonium Nitrogen from Milking Parlor Wastewater Using Pomegranate Peel Powder for Sustainable Water, Resources, and Waste Management

“…= k₂(Qe − Qt)2, Equations (4) and (5) are equations and linearized forms of the pseudo-second order model, respectively. dQt dt = k2(Qe − Qt)2,…”

“…Ammonium nitrogen (NH4-N) is one of the main components of milking parlor wastewater [2], and when in excess concentration, its release into bodies of water leads to serious environmental ramifications such as eutrophication, acid deposition, reactive nitrogen emissions, global warming, and over-fertilized soils [3,4]. Nitrogen is often regarded as the most essential and determinant nutrient for plant growth and crop yield [3]; therefore, its recovery is crucial, especially in communities with an increasing food demand and an indiscriminate use of chemical fertilizers [5]. Current wastewater treatment technologies place a heavy burden on dairy farm management, thus illustrating the need for simple, robust, and effective technology that requires low investment and maintenance costs [6].…”

Sustainable Sewage Sludge Management: From Current Practices to Emerging Nutrient Recovery Technologies

“…The amount of nitrogen in the reject water depends on the sludge type as well as the extent and configuration of the wastewater treatment. About 30% of the nitrogen in the sidestream, accounting for 4% of the nitrogen in wastewater, can be recovered [15,16]. Although this is far less than the agriculture needs for artificial fertilizer, N-recovery from wastewater might be part of a bigger sustainable solution.…”

Precious Data from Tiny Samples: Revealing the Correlation Between Energy Content and the Chemical Oxygen Demand of Municipal Wastewater by Micro-Bomb Combustion Calorimetry

“…However, WWTPs consume considerable amounts of electric energy and chemicals for treating wastewater, although wastewater contains 4-6 times more chemical energy than is required for its treatment using conventional technologies (Metcalf ＆ Eddy, Inc et al, 2014;Scherson and Criddle, 2014;Wan et al, 2016;Korth et al, 2017). Thus, reducing energy consumption while increasing energy and resource recovery (e.g., phosphorus and nitrogen) (van der Hoek et al, 2018;Vučić et al, 2021) are necessary improvements for transforming WWTPs from energy sinks to energy-autarkic or even energy-producing facilities.…”