Techno-economic feasibility of recovering phosphorus, nitrogen and water from dilute human urine via forward osmosis

Volpin, Federico,Heo, Huijin,Hasan Johir, Md Abu,Cho, Jaeweon,Phuntsho, Sherub,Shon, Ho Kyong Elsevier 2019 Water research Vol.150 No.-

<P><B>Abstract</B></P> <P>Due to high phosphorus (P) and nitrogen (N) content, human urine has often proven to suitable raw material for fertiliser production. However, most of the urine diverting toilets or male urinals dilute the urine 2 to 10 times. This decreases the efficiency in the precipitation of P and stripping of N. In this work, a commercial fertiliser blend was used as forward osmosis (FO) draw solution (DS) to concentrate real diluted urine. During the concentration, the urea in the urine is recovered as it diffuses to the fertiliser. Additionally, the combination of concentrate PO<SUB>4</SUB> <SUP>3-</SUP>, reverse Mg<SUP>2+</SUP> flux from the DS and the Mg<SUP>2+</SUP> presents in the flushing water, was able to recover the PO<SUB>4</SUB> <SUP>3-</SUP> as struvite. With 50% concentrated urine, 93% P recovery was achieved without the addition of an external Mg<SUP>2+</SUP>. Concurrently, 50% of the N was recovered in the diluted fertiliser DS. An economic analysis was performed to understand the feasibility of this process. It was found that the revenue from the produced fertilisers could potentially offset the operational and capital costs of the system. Additionally, if the reduction in the downstream nutrients load is accounted for, the total revenue of the process would be over 5.3 times of the associated costs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> 50% water recovery achieved with real urine as feed and commercial fertiliser blend as draw. </LI> <LI> 93% phosphorous recovery as struvite without additional Mg<SUP>2+</SUP> supply. </LI> <LI> 50% nitrogen recovery was achieved. </LI> <LI> pH below 6.5 necessary to avoid membrane scaling. </LI> <LI> OPEX and CAPEX of the process were investigated. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Human urine as a forward osmosis draw solution for the application of microalgae dewatering

Volpin, Federico,Yu, Hyeonjung,Cho, Jaeweon,Lee, Changsoo,Phuntsho, Sherub,Ghaffour, Noreddine,Vrouwenvelder, Johannes S.,Shon, Ho Kyong Elsevier 2019 Journal of hazardous materials Vol.378 No.-

<P><B>Abstract</B></P> <P>Human urine is a unique solution that has the right composition to constitute both a severe environmental threat and a rich source of nitrogen and phosphorous. In fact, between 4–9% of urine mass consists of ions, such as K<SUP>+</SUP>, Cl<SUP>−</SUP>, Na<SUP>+</SUP> or NH<SUB>4</SUB> <SUP>+</SUP>. Because of its high ionic strength, urine osmotic pressure can reach values of up to 2000 kPa. With this in mind, this work aimed to study the effectiveness of real urine as a novel draw solution for forward osmosis. Water flux, reverse nitrogen flux and membrane fouling were investigated using fresh or hydrolysed urine. Water flux as high as 16.7 ± 1.1 L m<SUP>−2</SUP> h<SUP>−1</SUP> was recorded using real hydrolysed urine.</P> <P>Additionally, no support layer membrane fouling was noticed in over 20 h of experimentation. Urine was also employed to dewater a <I>Chlorella vulgaris</I> culture. A fourfold increase in algal concentration was achieved while having an average flux of 14.1 L m<SUP>−2</SUP> h<SUP>−1</SUP>. During the algae dewatering, a flux decrease of about 19% was noticed; this was mainly due to a thin layer of algal deposition on the active side of the membrane. Overall, human urine was found to be an effective draw solution for forward osmosis.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Hydrolysed urine can reach more than 2000 kPa in osmotic pressure. </LI> <LI> Real urine exhibited flux up to 16.7 ± 1.1 L m<SUP>−2</SUP> h<SUP>−1</SUP>. </LI> <LI> Support layer fouling caused by unfiltered urine was found negligible. </LI> <LI> Four times algal concentration was achieved using real urine as draw solution. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Hybrid forward osmosis-reverse osmosis for wastewater reuse and seawater desalination: Understanding the optimal feed solution to minimise fouling

Volpin, Federico,Fons, Emilie,Chekli, Laura,Kim, Jung Eun,Jang, Am,Shon, Ho Kyong Elsevier 2018 Process safety and environmental protection Vol.117 No.-

<P><B>Abstract</B></P> <P>To enhance the seawater desalination energy efficiency forward osmosis – reverse osmosis (FO-RO) hybrid system has recently been developed. In this process, the FO “pre-treatment” step is designed to use seawater (SW) as draw solution to filter the wastewater (WW) while reducing the seawater osmotic pressure. Thereby reducing the operating pressure of the RO to desalinate the diluted SW. However, membrane fouling is a major issue that needs to be addressed. Proper selection of suitable WWs is necessary before proceeding with large-scale FO-RO desalination plants. In this study, long-term experiments were carried out, using state-of-the-art FO membrane, using real WW and SW solutions. A combination of water flux modelling and membrane characterisation were used to assess the degree of membrane fouling and the impact on the process performance. Initial water flux as high as 22.5Lm<SUP>−2</SUP> h<SUP>−1</SUP> was observed when using secondary effluent. It was also found that secondary effluent causes negligible flux decline. On the other hand, biologically treated wastewater and primary effluent caused mild and severe flux decline respectively (25% and 50% of flux decline after 80 hours, compared to no-fouling conditions). Ammonia leakage to the diluted seawater was also measured, concluding that, if biologically treated wastewater is used as feed, the final NH<SUB>4<SUP>+</SUP> </SUB> concentration in the draw is likely to be negligible.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Commercial state-of-the-art FO membranes were tested with real wastewater and seawater. </LI> <LI> Initial water flux of 22.5 Lm<SUP>−2</SUP> h<SUP>−1</SUP> was observed. </LI> <LI> Secondary effluent wastewater caused negligible fouling over long term operation. </LI> <LI> Ammonia leakage to the seawater was negligible. </LI> </UL> </P>

[기조연설 Ⅳ] The ICRC at 150: Current challenges to humanitarian action

Gianni VOLPIN 대한적십자사 인도법연구소 2014 人道法論叢 Vol.- No.34

Ammonia recovery from human urine as liquid fertilizers in hollow fiber membrane contactor: Effects of permeate chemistry

Mekdimu Mezemir Damtie,Federico Volpin,Minwei Yao,Leonard Demegilio Tijing,Ruth Habte Hailemariam,Teng Bao,Kwang-Duck Park,Ho Kyong Shon,June-Seok Choi 대한환경공학회 2021 Environmental Engineering Research Vol.26 No.1

The production of the existing nitrogen fertilizer is costly and less environmental-friendly. Various green technologies are currently emerging toward providing alternative options. In this study, a liquid/liquid hydrophobic hollow-fiber membrane contactor was employed at ambient temperature and natural urine pH ~ 9.7 to recover ammonium fertilizers from human urine. Results showed that permeate side chemistry was one of the major factors affecting the ammonia mass transfer. The study on the ammonia capturing performance of diluted sulfuric acid, phosphoric acid, nitric acid, and DI water confirmed that acid type, acid concentration, and permeate side operating pH were the most important parameters affecting the ammonia capturing tendency. Sulfuric acid was slightly better in capturing more ammonia than other acid types. The study also identified increasing acid concentration didn’t necessarily increase ammonia mining tendency because there was always one optimum concentration value at which maximum ammonia extraction was possible. The best permeate side operating pH to extract ammonia for fertilizer purposes was selected based on the dissociation equilibrium of different types of acids. Accordingly, the analysis showed that the membrane process has to be operated at pH > 3 for sulfuric acid, between 3.5 to 11.5 for phosphoric acid, and above 0.5 for nitric acid so as to produce their respective high-quality liquid ammonium sulfate, ammonium monophosphate/diphosphate, and ammonium nitrate fertilizer. Therefore, permeate side acid concentration, pH, and acid type has to always be critically optimized before starting the ammonia mining experiment.

[패널토의] “오늘날의 국제인도법과 인도적 활동의 도전과제”

Vincent Bernard(사회자),최영진(토론자),Stella Ogunlade(토론자),Antonio Donini(토론자),Gianni Volpin(토론자),김주자(토론자) 대한적십자사 인도법연구소 2014 人道法論叢 Vol.- No.34