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Article

Evaluating the Applicability of High-Speed Air Flotation Technology for Water Supply: A Case Study in Tianjin Binhai New Area

by
Shuyan Gong
1,
Hongpeng Wang
1,*,
Shuang Zhang
1,
Shaohong Jiang
1,
Xinjuan Zhao
2 and
Qidong Hou
3,*
1
Tianjin Tanggu Sino French Water Supply Company Limited, Tianjin 300450, China
2
Tianjin Hua Miao Research & Design Institute of Water & Wastewater Company Limited, Tianjin 300220, China
3
National & Local Joint Engineering Research Center of Biomass Resource Utilization, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
*
Authors to whom correspondence should be addressed.
Separations 2022, 9(11), 362; https://doi.org/10.3390/separations9110362
Submission received: 12 October 2022 / Revised: 4 November 2022 / Accepted: 7 November 2022 / Published: 9 November 2022
(This article belongs to the Section Environmental Separations)
Browse Figures
Versions Notes

Abstract

:
The development and application of advanced water purification technology is crucial to guarantee a sufficient supply of clean water. However, conventional water purification technology consumes large amounts of coagulants, with the formation of intractable sludge. Herein, the applicability of high-speed air flotation technology for the purification of actual water sources was evaluated in Tianjin Binhai New Area. During a three-year survey, the raw water exhibited periodic pollution characteristics with algae cells as the main removal targets in all seasons. The raw water had both low temperatures and low turbidity in winter, another obstacle for water treatment. Based on the scientific analysis of the water’s quality, the water purification process was comprehensively optimized via regulating the dosage of agents and operating parameters and using high-speed air flotation equipment. The results showed that a dissolved air pressure of 0.40 MPa, reflux ratio of 8%, and SUEZ-1# dissolved air release head combined with pre-chlorination with PACl plus FeCl3 (PACl/FeCl3 ratio = 2:1) were suitable for attaining a good purification performance. High turbidity removal rates (80.9–86.2%) and algae cell removal rates (92.5–98.1%) were obtained even in the high algae period of summer and low turbidity period in the winter, proving the superior stability and applicability of the high-speed air flotation system.

Graphical Abstract

1. Introduction

The sufficient supply of clean water is of great importance for the health of human beings and the sustainable development of modern industry [1]. Meeting the goal of “clean water and sanitation”, the sixth of the sustainable development goals of the United Nations, has become a worldwide mission [2,3,4]. However, the quality of river water and underground water has seriously deteriorated due to continuous experimental pollution and ecological deconstruction [5], posing great threats to water supply. According to the World Health Organization’s (WHO’s) standards, 28% of the groundwater samples in China from 2000 to 2012 did not meet the quality criteria [6]. In 2010, as high as 36% of river sections and 40% of major lakes in China were not capable of being employed as drinking water sources [2]. China has implemented a series of effective policies and measures, such as the “South-to North Water Transfer Project” and “Water Pollution Prevention & Control Action Plan”, to guarantee the security of drinking water [7].
Tianjin city, as a large city extremely short of water, faces tremendous challenges with the growing development of agricultural and economic activities [8]. A majority of the water supply of Tianjin city is transferred from the Yangtze River and the Luan River, with the implementation of the South-to-North Water Transfer Project in December of 2014 [9,10]. In summer and autumn, the water resource is mainly from the Yangtze River, with relatively good water quality. However, in spring and winter, the water resource is mainly from the Luan River, with relatively poor quality. The water quality fluctuates remarkably, as evidenced by many water quality indexes including turbidity, algae content, and organic matter contents, which are obviously higher than that of the Yangtze River. In summer, the water resource has a high algae content dominated by cyanobacteria and green algae. In autumn, green algae is the main algae species. The existence of large amounts of algae poses a great challenge for the purification of water.
Sedimentation tanks are widely used for water treatment, with polyaluminium chloride (PACL) and/or ferric chloride (FeCl3) as coagulants. Horizontal sedimentation tanks have the advantages of low cost, good applicability, good performance, and simple operation [11]. However, horizontal sedimentation tanks usually require large areas with uneven water distribution and complicated sludge discharge equipment. In contrast, inclined plate sedimentation tanks have higher efficiency rates with lower area requirements, but they face the difficulties of construction and being blocked by sludge and the growth of algae [12,13]. The common problem of current water purification technology is its large-scale consumption of coagulants, accompanied by the formation of intractable sludge. In this context, a high-speed air flotation which use microbubbles to boost the water purification process has emerged as an alternative technology [14]. In this study, we evaluate the applicability of high-rate air flotation for water supply from the Yangtze River in summer and autumn. The verification of the applicability of this high-rate air flotation technology would provide theoretical guidance and technical support for its large-scale application in the Beijing-Tianjin-Hebei Region.

2. Materials and Methods

Air flotation is used to separate solids and solutions by inletting large amounts of microbubbles into water after coagulation [15,16]. In this process, the hydrophobic particulates, or tiny flocculent particles, which have a similar density to water, adhere to the microbubbles to form a microbubble–floc composite with a low density [17,18,19]. Owing to its buoyancy force, the microbubble–floc composite floats to the surface of the water to form a scum zone, which can be removed by a scraper [14,20,21,22]. High-speed air flotation technology uses pressurized dissolved air to generate 10–100 μm microbubbles. Compared with traditional air flotation, high-speed air flotation technology features a high hydraulic loading rate (20–40 m/h) with a comparable flocculation time (5–10 min).
High-speed air flotation equipment is based on reflow booster pumps, air compressors, and pressure saturators, as schematically shown in Figure 1. The compressed air provided by the air compressor combined with the return water from the booster pump forms a stable gas–liquid interface in the dissolved gas tank [23,24,25]. Through the interfacial mass transfer, the compressed air is dispersed into a supersaturated dissolved gas water in the form of dissolved gas molecules and non-dissolved tiny gas nuclei [26,27]. The supersaturated dissolved gas water is injected into untreated water to discharge microbubbles through a specific dissolved gas release head at the end of the system. The tiny bubbles collide with organic matter, the hydrophobic suspension, and algae to form flocculus to be carried the water’s surface by the bubbles in order to realize the separation of the gas–liquid–solid phases [28,29].
The size of the high-speed air flotation device is L × D × H = 8 m × 2.5 m × 3.7 m, with a floor area of 80 m2. The water treatment rate is 80–120 m3/h, and the total weight of the device is approximately 40 tons (under a full load). The whole device is divided into four parts, which include the coagulation zone, flocculation zone, pressurized water mixing zone, and the high-speed air flotation zone, as follows:
(a)
In the coagulation zone, according to the differing quality of the raw waters, the optimal amount of coagulant is determined, based on the coagulation experiment, using polyaluminium chloride (PACL) and or ferric chloride (FeCl3) as coagulants (coagulation time: 1–2 min).
(b)
In the flocculation zone, hydraulic flocculation is used to facilitate the combination of flocculants with microbubbles, with flocculation times of 5–10 min.
(c)
The pressurized water mixing zone includes dissolved gas systems and degassing systems. The dissolved gas system is composed of a reflux booster pump, an air compressor, and a pressure dissolved gas tank. The pressured gas tank is a filler-type dissolved gas tank with an increased mass transfer area of the gas–liquid diphase to improve the dissolved gas efficiency. In the gas release system, the unique dissolved air release head efficiently generates tiny bubbles (with bubble diameters of approximately 40 μm). The arrangement of the dissolved air release head ensures the uniform distribution of microbubbles in the flotation area.
(d)
The area of the flotation area is 2.93 m2, with a hydraulic load of 25.6 m/h and dissolved air pressure water circulation proportion of 5–15%. The unique water trap design enables the entire flotation pool’s surface to be used to collect water. The overall flow state is uniform to reduce the influence of the turbulent flow state on separation, resulting in better anti-interference ability. The formed laminar flow upflows at rate of 20–40 m/h. Since the bubbles and flocculants in the pressured water mixing zone are fully collided, copolymerized, and greatly complexed under the action of wrapping, mesh trapping, and bridging, the upward floating speed is fast during solid–liquid separation. At the same time, the flotation selection area is induced to generate a thicker uniform bubble bed, with the purified water flowing out from the bottom.
To explore the effects of pre-chlorination (NaClO was used to guarantee a free residual chlorine content of 0.1 mg/L) and different combinations of coagulants on the effects of the high-speed air flotation treatment, six treatments were set: no pre-chlorination plus PACl, pre-chlorination plus PACl, no pre-chlorination plus PACl plus FeCl3 (PACl/FeCl3 ratio = 1:1), no pre-chlorination plus PACl plus FeCl3 (PACl/FeCl3 ratio = 2:1), pre-chlorination plus PACl plus FeCl3 dosing (PACl/FeCl3 ratio = 1:1), and pre-chlorination plus PACl+FeCl3 (PACl/FeCl3 ratio = 2:1). The total amount of reagents was constant in the different treatments.
The turbidity of the water samples was measured on a turbidimeter (TL2300, HACH). The ammonia nitrogen content was determined at 420 nm on a spectrophotometer (T6, PERSEE) using Nessler reagent as an indicator. The pH was recorded on a pH meter (FE20, METTLER TOLEDO). The absorbance at 254 nm (UV254) was recorded on a spectrophotometer (T6, PERSEE) as an indicator of humins and aromatic compounds. The alkalinity was determined by acid-base titration using methyl orange as an indicator. The chemical oxygen demand (CODMn) was measured using potassium permanganate as an oxidant. The algal cell concentration was observed by microscope (OLYMPUS BX25). The content of chlorophyll a was determined by the spectrophotometric method [30].

3. Results and Discussion

3.1. Raw Water Characteristics

The quality of the raw water over the preceding three years was evaluated and comprehensively analyzed. As shown in Figure 2, the quality of the raw water exhibited periodic variations with the seasons. The turbidity, ammonia nitrogen content, CODMn, and algal cell concentration exhibited pollution features in certain seasons. In particular, from March to May and from September to December, algae grew wildly, with increases in CODMn, ammonia nitrogen content, and odor. Using a conventional process makes it difficult to achieve the desired water purification performance due to a series of complex factors.
Since the turbidity, ammonia nitrogen content, pH, UV254, alkalinity, CODMn, and algal cell concentration changed periodically, the process parameters needed to be regulated frequently in order to deal with the heavy pollution. Particularly, the pH and alkalinity had a great influence on the required dosage of reagents, and they also affected the resultant residual aluminum and residual iron. Therefore, the dosage of reagents was cautiously regulated to guarantee a favorable flocculation performance, especially when the raw water had a high pH and low alkalinity.
Algal cells were major pollutant for the water resources from both the Luan River and the Yangtze River, and it is a predominant problem in all the seasons. Algae would block filters and reduce the backwashing intervals of filters. Meanwhile, the presence of algae would also lead to the increases in turbidity, accompanied by a series of problems, such as odor. The concentration of algal cells generally increased rapidly when switching water resources with the reduction of alkalinity, resulting in difficulty in removing algae.
The water resources had both low temperatures and low turbidity in winter, with temperatures as low as 5 °C and turbidity levels as low as 1.07 NTU. Due to the presence of large amounts of homogenic colloidal particles with low amounts of foreign particles, as well as the strong electrostatic repulsion induced by the negative potential of the particles, the efficient collision and flocculation to form floc particles was inhibited [31,32,33]. To solve this problem, the common method used is to improve the dosage of coagulants. Even so, it is still difficult to achieve the desired flocculation performance. This also increases the burden on filters and the self-consumption of water, with the risk of residual aluminum and residual iron exceeding the allowed standards.
Overall, the raw water was characterized by “low temperature, low turbidity and high algae content”. The turbidity of the raw water was below 10 NTU, with organic pollutants changing periodically. Algae cells are the main removal targets for both the Yangtze River and the Luan River in all seasons. When the raw water was switched from the Yangtze River to the Luan River, the concentration of algae cells in the raw water increased significantly in a short period of time. In winter, the raw water had both low temperatures and low turbidity, with minimum temperatures of below 5 ℃ and turbidity as low as 1.07 NTU.

3.2. Effect of Reagents on Treatment Performance

In the air flotation water purification process, the treatment performance depends heavily on the amount of coagulant. The addition of an appropriate amount of coagulant is helpful for producing flocculants with high compactness and a high probability of collision between them for a good purification performance. When too much coagulant is applied, the coagulant allows the solution to be positively charged [34,35]. The positively charged colloidal particles result in the stabilization of destabilized particles once again, reducing the air flotation treatment performance [36,37,38].
Organic matter and algae usually show a strong disadvantageous influence on the coagulation and precipitation process since multinuclear coordinated complexes composed of aluminum ion and organic matter are hard to destabilize [39]. The experimental results showed that pre-chlorination can significantly decrease the turbidity, with a good algal cell removal rate, since NaClO can kill algae and organisms via a strong oxidation effect. As a result, the interference effect of the organic matter and algae on the subsequent coagulation and precipitation process was alleviated, with the inhibition of algae breeding in the sedimentation tanks and filter tanks to ensure the purification performance.
Individual additions of PACl led to turbidity removal rates of 64.2–83.4% (Figure 3a) with algal cell removal rates of 60.6–86.3% (Figure 3b). The combination of PACl with FeCl3 at a 1:1 ratio provided slightly higher turbidity removal rates of 65.3–85.1% (Figure 3c) with algal cells removal rates of 60.1–90.6% (Figure 3d), while the PACl with FeCl3 at a 2:1 ratio provided obviously higher turbidity removal rates (68.4–88.7%) with algal cell removal rates of 63.5–98.6%. When using PACl alone, large amounts of reagents are required to achieve the desired purification performance, with the occurrence of excess aluminum in the effluent water. Considering the purification performance and operation difficulty, pre-chlorination plus PACl plus FeCl3 (PACl/FeCl3 ratio = 2:1) was selected.
In summary, pre-chlorination treatments significantly improved the turbidity removal rates and algae cell removal rates since NaClO can greatly reduce the interference of organic matter and algae and effectively prevent the growth of algae in the sedimentation tanks and filter tanks. The combination of pre-chlorination with PACl plus FeCl3 (PACl/FeCl3 ratio = 2:1) provided the best water purification performance.

3.3. Effect of Operating Parameters on Treatment Performance

3.3.1. Pressure of Dissolved Air

Whether the flocculent particles can be fully removed is mainly determined by the quality of the dissolved gas condition. Dissolved gas pressure affects the size and number of formed microbubbles. When the microbubbles are stable, the pressure of the dissolved gas is proportional to the amount of dissolved gas. However, excessive pressure will reduce the amount of gas-dissolved water, resulting in undissolved gas in the dissolved gas tank and release of the larger bubbles, causing a strong disturbance in the air flotation system [40]. This is not conducive to the air flotation process, with an increase in the energy consumption of the dissolved gas pump. Therefore, the appropriate pressure of dissolved gas is of great importance.
At a relatively low pressure (0.35 MPa) of dissolved air, the turbidity removal rates were 42.6–71.6% (Figure 4a) and the algal cell removal rates were 68.6–82.4% (Figure 4b). Due to the low release frequency of the fine bubbles, the suspended floc could not adhere to the bubbles and float up sufficiently. These results indicate that the treatment process was dominated by the flocculation and coagulation process at low pressure. As the pressure increased from 0.35 MPa to 0.40 MPa, the turbidity and algal cell removal rates increased to 87.2% and 97.9% at coagulant dosages of 18 mg/L, respectively. The emulsification phenomenon was observed in the pool, indicating that the dissolved gas system was normal under this pressure. When the pressure was larger than 0.40 MPa, the turbidity and algal cell removal rates improved greatly for all dosages of coagulant. Meanwhile, the effect of increasing the dosage on the turbidity and algal cell removal rates was the same, regardless of the pressure is used. This was likely due to the turbulence of the water flow during the floating process. Comprehensively considering the purification performance and energy consumption, the appropriate pressure was 0.4 MPa.

3.3.2. Reflux Ratio

A reflux ratio can approximately represent the amount of air in an air flotation process. When the pressure of the dissolved air and water flow are fixed, the reflux ratio is proportional to the amount of the dissolved air in the liquid [38,41,42,43]. We investigated the influence of the reflux ratio using the pre-chlorination plus PACl plus FeCl3 (PACl/FeCl3 ratio = 2:1) treatment under 0.4 MPa pressure.
When the reflux ratio was 5%, both the turbidity (Figure 4c) and algal cell removal rates (Figure 4d) were low. This was due to the small amount of bubbles generated by the air flotation system to allow for the copolymerization of the bubbles and flocs. When the reflux ratio was raised from 5 to 8%, the removal rates of turbidity (74.7% to 86.8%) and algal cells (from 74.2% to 98.1) improved greatly due to the increase in bubbles in the liquid. However, when the reflux ratio was further improved to 10%, the removal rates only increased slightly. In view of both energy consumption and purification performance, 8% was the optimal reflux ratio.

3.4. Effect of the Dissolved Air Releasing System on Treatment Performance

3.4.1. Effect of Dissolved Air Release Head

The dissolved air release head is an important unit for generating microbubbles. The performance of the dissolved air release head will directly affect the quality of the dissolved air bubbles, thus affecting the water purification efficiency and energy utilization of the entire air flotation process [44,45,46,47]. Here, we selected three types of release heads (SUEZ-1# (inlet diameter: 7.5 mm, outlet diameter: 3.5 mm, and outlet flow: 1.3–1.6 m3/h), SUEZ-2# (inlet diameter: 5 mm, outlet diameter: 2 mm, and outlet flow: 0.5–0.8 m3/h), and HuaM-3# (inlet diameter: 5 mm, outlet diameter: 3 mm, and outlet flow: 0.7–0.85 m3/h)) to explore their impacts on the water purification performance.
It was observed that the water purification performance of the SUEZ-1# and SUEZ-2# emitters was significantly better than that of the HuaM-3# emitters (Figure 5). Moreover, the turbidity removal rates and algae cell removal rates of the SUEZ-1# emitters were slightly higher than those of the SUEZ-2 # emitters. The relatively large diameter of the SUEZ-1# release head ensured good pressure relief and energy dissipation performance.
For the SUEZ-2 # and HuaM-3# emitters, the turbulence intensity was large due to the small opening diameters and the local resistance coefficients at the openings of the release heads becoming larger. Turbulence increased the probability of microbubbles colliding with each other, and it was not conducive to the uniformity and stability of the bubbles, leading to a reduction in water purification performance. Further, HuaM-3# was noisy in actual operation. Considering the water purification performance and environmental safety, SUEZ-1# was chosen as the best dissolved gas release head for this process.

3.4.2. Effect of Filler on Water Purification

To explore the influence of filler on the water treatment performance, a plastic stepped ring was added, with filling ratios of 0%, 50%, and 100%, respectively. In the absence of filler in the air tank, the turbidity removal rates were 53.6–86.5% (Figure 6a) and the algae cell removal rates (Figure 6b) were 79.8–97.9%. When filler ratios of 50% and 100% were added to the air tank, the removal rates of algae cells were reduced slightly. After long-term operation, plastic biofilms formed on the surface of the plastic stepped ring, which reduced the gas–liquid contact area in the air tank and the gas dissolution efficiency. Therefore, it was unnecessary to add filler to the air dissolving tank.

3.5. Effect of Water Resource in Different Seasons on Treatment Performance

To explore the stability and applicability of the high-speed air flotation system, the water purification performance in summer and winter was investigated (Figure 7). In winter, with low turbidity, the high-speed air flotation system still afforded turbidity removal rates of up to 86.2% with algae cell removal rates of up to 92.5%. In the high algae period of summer, the turbidity removal rates reached 86.2% with algae cell removal rates as high as 98.1%. These results confirmed that the high-speed air flotation system could stably and efficiently function throughout the whole year, with superior stability and applicability. Comparatively, the water treatment performance in summer was slightly better than that in winter, likely due to the influence of temperature on the coagulation process. In winter, the hydrolysis of PACl and FeCl3 was 2–4 times slower than that in summer, with low movement rates of colloidal particles in water, which is adverse to the destabilization and flocculation of the colloidal particles [15].
Through optimizing the reaction conditions, the dissolved air pressure of 0.40 MPa, reflux ratio of 8%, and SUEZ-1# dissolved air release head were selected, without adding filler to the air tank. Under this condition, large amounts of microbubbles of a small size were generated, affording the best performance. Even in the high algae period of summer and low turbidity period in the winter, the high-speed air flotation system still provided turbidity removal rates as high as 80.9–86.2% and algae cell removal rates as high as 92.5–98.1%, verifying the excellent stability and applicability of the high-speed air flotation system.

4. Conclusions

In this study, we comprehensively evaluated the applicability of a high-speed air flotation technology for the purification of actual water sources as an alternative to the traditional process. The raw water had periodic pollution characteristics. Algae cells were the main removal targets in all seasons. In winter, the raw water had both low temperatures and low turbidity. Through optimizing the reaction conditions, a dissolved air pressure of 0.40 MPa, reflux ratio of 8%, and SUEZ-1# dissolved air release head, in combination with pre-chlorination by PACl plus FeCl3 (PACl/FeCl3 ratio = 2:1), were selected to attain a good purification performance. Even in the high algae period of summer and low turbidity period in the winter, turbidity removal rates as high as 80.9-86.2% with algae cell removal rates as high as 92.5–98.1% were achieved, proving the superior stability and applicability of the high-speed air flotation system.

Author Contributions

Conceptualization, S.G. and H.W.; methodology, Q.H.; software, Q.H.; validation, S.G., H.W. and S.Z.; formal analysis, S.J.; investigation, S.Z.; resources, X.Z.; data curation, X.Z.; writing—original draft preparation, H.W.; writing—review and editing, H.W.; visualization, S.J.; supervision, S.Z.; project administration, S.G.; funding acquisition, S.G. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Conflicts of Interest

The authors declare no conflict of interest.

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Figure 1. Schematic illustration of the high-speed air flotation equipment.
Figure 1. Schematic illustration of the high-speed air flotation equipment.
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Figure 2. (a) Turbidity and ammonia nitrogen content of the raw water from 2019 to 2021; (b) pH and alkalinity of the raw water from 2019 to 2021; (c) CODMn and UV254 of the raw water from 2019 to 2021; and (d) algal cell concentration and chlorophyll a of the raw water from 2019 to 2021.
Figure 2. (a) Turbidity and ammonia nitrogen content of the raw water from 2019 to 2021; (b) pH and alkalinity of the raw water from 2019 to 2021; (c) CODMn and UV254 of the raw water from 2019 to 2021; and (d) algal cell concentration and chlorophyll a of the raw water from 2019 to 2021.
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Figure 3. (a) Impact of the dosage of PACl on turbidity removal rates with or without pre-chlorination; (b) impact of the dosage of PACl on algal cell removal rates with or without pre-chlorination; (c) impact of the dosage and ratio of PACl and FeCl3 on turbidity removal rates with or without pre-chlorination; and (d) impact of the dosage and ratio of PACl and FeCl3 on algal cell removal rates with or without pre-chlorination.
Figure 3. (a) Impact of the dosage of PACl on turbidity removal rates with or without pre-chlorination; (b) impact of the dosage of PACl on algal cell removal rates with or without pre-chlorination; (c) impact of the dosage and ratio of PACl and FeCl3 on turbidity removal rates with or without pre-chlorination; and (d) impact of the dosage and ratio of PACl and FeCl3 on algal cell removal rates with or without pre-chlorination.
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Figure 4. Impact of the pressure of the dissolved air on the turbidity removal rate (a) and algal cell removal rate (b); and the impact of the reflux ratio on the turbidity removal rate (c) and algal cell removal rate (d).
Figure 4. Impact of the pressure of the dissolved air on the turbidity removal rate (a) and algal cell removal rate (b); and the impact of the reflux ratio on the turbidity removal rate (c) and algal cell removal rate (d).
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Figure 5. Impact of the dissolved air release head on the turbidity removal rates (a) and algal cell removal rates (b).
Figure 5. Impact of the dissolved air release head on the turbidity removal rates (a) and algal cell removal rates (b).
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Figure 6. Impact of filler on turbidity removal rates (a) and algal cell removal rates (b).
Figure 6. Impact of filler on turbidity removal rates (a) and algal cell removal rates (b).
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Figure 7. The turbidity removal rates (a) and algal cell removal rates (b) for the water resources in different seasons.
Figure 7. The turbidity removal rates (a) and algal cell removal rates (b) for the water resources in different seasons.
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MDPI and ACS Style

Gong, S.; Wang, H.; Zhang, S.; Jiang, S.; Zhao, X.; Hou, Q. Evaluating the Applicability of High-Speed Air Flotation Technology for Water Supply: A Case Study in Tianjin Binhai New Area. Separations 2022, 9, 362. https://doi.org/10.3390/separations9110362

AMA Style

Gong S, Wang H, Zhang S, Jiang S, Zhao X, Hou Q. Evaluating the Applicability of High-Speed Air Flotation Technology for Water Supply: A Case Study in Tianjin Binhai New Area. Separations. 2022; 9(11):362. https://doi.org/10.3390/separations9110362

Chicago/Turabian Style

Gong, Shuyan, Hongpeng Wang, Shuang Zhang, Shaohong Jiang, Xinjuan Zhao, and Qidong Hou. 2022. "Evaluating the Applicability of High-Speed Air Flotation Technology for Water Supply: A Case Study in Tianjin Binhai New Area" Separations 9, no. 11: 362. https://doi.org/10.3390/separations9110362

APA Style

Gong, S., Wang, H., Zhang, S., Jiang, S., Zhao, X., & Hou, Q. (2022). Evaluating the Applicability of High-Speed Air Flotation Technology for Water Supply: A Case Study in Tianjin Binhai New Area. Separations, 9(11), 362. https://doi.org/10.3390/separations9110362

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