The American Journal of Engineering and Technology
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TYPE
Original Research
PAGE NO.
79-87
10.37547/tajet/Volume07Issue07-09
OPEN ACCESS
SUBMITTED
06 June 2025
ACCEPTED
24 June 2025
PUBLISHED
22 July 2025
VOLUME
Vol.07 Issue 07 2025
CITATION
Andrii Odnoralov. (2025). Comprehensive Analysis of Physico-Chemical
and Biological Mechanisms of Reverse Osmosis Membrane Fouling with
the Development and Optimization of Preventive Strategies to Enhance
the Operational Stability of Membrane Systems. The American Journal
of Engineering and Technology, 7(07), 79
–
87.
https://doi.org/10.37547/tajet/Volume07Issue07-09
COPYRIGHT
© 2025 Original content from this work may be used under the terms
of the creative commons attributes 4.0 License.
Comprehensive Analysis of
Physico-Chemical and
Biological Mechanisms of
Reverse Osmosis
Membrane Fouling with
the Development and
Optimization of Preventive
Strategies to Enhance the
Operational Stability of
Membrane Systems
Andrii Odnoralov
"Technical Director", Jordan water; "Director", Fisoniya LLC Kiev,
Ukraine
Abstract:
This article presents a comprehensive analysis
of the physicochemical and biological mechanisms
underlying reverse-osmosis membrane fouling, along
with the development and optimization of preventive
strategies to enhance the operational stability of
membrane systems. The relevance of this research is
determined by the growing freshwater scarcity and the
rapid expansion of desalination capacities, where over
65% of produced water is obtained through reverse
osmosis. The work aims to integrate classical and
modern non-invasive fouling diagnosis methods
—
from
SEM-EDS, ATR-FTIR, and XPS to optical coherence
tomography and online ATP/BGP sensors
—
to delineate
four primary foulant types and identify key intervention
points at the early stages of deposit formation. The
novelty of the study lies in the design and optimization
of cascade preventive strategies that combine fine
physicochemical pretreatment, targeted chemistry, and
adaptive control of cleaning and reagent dosing
protocols via machine-learning algorithms. The
proposed closed-loop control model
—
from deep
diagnostics to automatic adjustment of operating
parameters
—
enables a substantial extension of the
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maintenance interval and a reduction in the total cost
per cubic meter of treated water. Key results
demonstrate that: Inorganic fouling can be effectively
suppressed by antiscalants and pH regulation,
preventing irreversible carbonate and sulfate deposit
formation; Organic deposits and colloidal particles are
most robustly removed by combining surfactant-
enhanced cleaning and membrane-surface modification
with hydrophilic coatings; Biofouling is controlled
through two-stage biocide protocols triggered by early
signals from ATP sensors, which reduces cleaning costs
and downtime to a critical minimum. Online monitoring
of hydraulic and biological markers is integrated with
trainable algorithms that flexibly adapt flow parameters
and chemical protection in real-time. This article will
appeal to specialists in membrane technology and
desalination, as well as researchers and developers of
reverse osmosis systems and preventive water quality
management strategies.
Keywords:
reverse osmosis; fouling; membrane
systems; preventive strategies; optical coherence
tomography; antiscalants; biofouling.
Introduction
Global growth in freshwater scarcity has compelled
nations to scale up their desalination capacity rapidly.
Open estimates for 2023 report approximately 18,000
plants in operation, with a combined output of nearly
100 million m³/day, of which over 65% is produced via
reverse osmosis (Ahmed et al., 2023). However, the
economic efficiency of the technology remains
vulnerable
—
membrane fouling complicates hydraulic
regimes, increases required pressure, and accelerates
module degradation. In full-scale systems, biofouling
and associated cleanings can raise operational
expenditures by 30 % or more (Sanawar et al., 2018),
while energy consumption often grows faster than
productivity: at one medium-size plant studied, energy
costs rose by 15 % over four years, while water output
increased by only 8.7 % (Feo-García et al., 2024). Given
that electricity can account for up to half the cost of
producing a cubic meter of water, fouling represents a
key barrier to further reducing desalination costs. It is
thus critically important for water security.
Modern analysis of fouling processes has evolved from
post-mortem autopsies of modules to continuous non-
invasive methodologies. The classical approach involves
characterizing the four dominant foulant types
—
namely, inorganic scaling, organic and colloidal deposits,
and biofilms
—
to inform reagent selection and cleaning
protocols (Ahmed et al., 2023). SEM-EDS, ATR-FTIR, and
XPS elucidate the layer morphology and chemistry,
while growth dynamics are now tracked via permeability
decline, transmembrane pressure rise, and signals from
online ATP sensors. Special attention is devoted to
optical coherence tomography. This method enables
real-time visualization of deposit thickness and
heterogeneity without opening spiral-wound modules,
thereby significantly improving the accuracy of
predictive models (Lee et al., 2023). This rich
experimental foundation supports both empirical
correlations and mechanistic series-resistance models,
complemented by machine learning for early warning of
atypical events.
The development of preventive strategies naturally
follows from this diagnostic paradigm: the finer the
mechanistic understanding, the earlier interventions
can be applied. In practice, the most robust outcomes
are achieved through a cascade combination of fine
physicochemical
pretreatments
(microfiltration,
coagulation, and controlled chlorination) with gentle
biocidal or photocatalytic actions that suppress
microbial activity without damaging the polyamide
membrane skin (Lee et al., 2023).
These measures are supplemented by antifouling,
hydrophilic self-cleaning polymer coatings, alongside
adaptive flow and recovery management, to maintain
shear velocity and salt-saturation levels beneath critical
thresholds. It is precisely the integration of such
measures
—
from deep diagnostics to agile regulation
and considered cleaning chemistry
—
that delivers a real
extension of module lifetime and reduction of overall
water cost, making fouling prevention a central focus of
ongoing research and engineering optimization in
membrane systems.
Materials and Methodology
This research draws on over 20 key publications on
fouling
analysis
in
reverse-osmosis
systems,
encompassing both academic articles and field-scale
reports. The theoretical basis comprises summaries of
operational statistics for 18,000 installations with a
SWRO share exceeding 65% (Ahmed et al., 2023) and
assessments of biofouling impacts on costs and energy
use in full-scale lines (Sanawar et al., 2018; Feo-García et
al., 2024). Methodologically, emphasis is placed on
integrating classical module-autopsy tools with modern
non-invasive diagnostic techniques (Lee et al., 2023).
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For morphological and chemical analyses of deposits,
scanning electron microscopy with energy-dispersive
analysis (SEM-EDS), attenuated-total-reflection Fourier-
transform infrared spectroscopy (ATR-FTIR), and X-ray
photoelectron spectroscopy (XPS) were employed,
complemented by optical coherence tomography (OCT)
for dynamic monitoring of layer thickness and
heterogeneity without breaching spiral-wound modules
(Lee et al., 2023). Fouling dynamics were assessed by
changes in permeability, growth in transmembrane
pressure, and signals from online adenosine
triphosphate (ATP) and biological growth potential
(BGP) sensors (Rezaei et al., 2020; Abushaban et al.,
2020).
Comparative analysis of the four deposit types included
laboratory tests on model foulants: inorganic scaling of
CaCO₃ and CaSO₄ at varied saturation indices and
temperatures (Pomerantz et al., 2006; Ashfaq et al.,
2019); organic deposition of humic acids with and
without nonionic surfactants (Kallapalli & Basu, 2025;
Gao et al., 2023); colloidal flocculation of silica and iron
oxides on unmodified and modified polyamide surfaces
(Lin et al., 2021; Pipich et al., 2021); and biofouling in
industrial-
module autopsies, quantified as CFU·cm⁻² and
correlated with TMP (Kucera, 2019; Hoek et al., 2022;
Vrouwenvelder et al., 2009).
The design and optimization of preventive strategies
were based on pilot- and full-scale trials of cascade
pretreatment
—
coagulation,
microfiltration,
and
controlled chlorination
—
to reduce organic and colloidal
fouling (Ahmed et al., 2023; Lee et al., 2023); application
of phosphonates and acrylic copolymers as antiscalants
(Verbeke et al., 2020; Lakner & Lakner, 2025); and
biocidal protection schemes employing metabisulfite
and photocatalytic complexes. For real-time control of
cleaning regimes and reagent dosing, machine-learning
algorithms were implemented to analyze flow data,
pressure differentials, and salt passage, automatically
adjusting process parameters (Roth et al., 2024).
Results and Discussion
The physicochemical picture of fouling in reverse-
osmosis modules can be reduced to four archetypes,
each distinguished by its dominant nucleation
mechanism, typical nutrient sources in the stream, and
characteristic permeability loss. Inorganic fouling
—
primarily carbonate and sulfate scaling
—
begins when
the local supersaturation rises faster than hydrodynamic
shear dispersion can mitigate. Autopsies of industrial
SWRO modules treated only by ultrafiltration showed
that calcium deposits comprise up to 77.5 % of the
foulant layer’s mass; the addition of an adsorptive pre
-
treatment halved this proportion while simultaneously
reducing transmembrane-
pressure (ΔP) in
crease by 10
–
30 % (Wang et al., 2022).
Retained salts crystallize as calcite, aragonite, or gypsum
and, under extreme concentrate-recovery ratios, can
collapse permeate flux to half its initial value (Rezaei et
al., 2020). Manufacturers, therefore, recommend
initiating acid cleaning once ΔP has risen by 15% to
prevent the transition into an irreversible stone‐crust
stage (Lakner & Lakner, 2025).
Organic fouling is generated by humic acids, surfactants,
and low-molecular-weight polar compounds that adsorb
onto the hydrophobic domains of polyamide and
penetrate pores via hydrogen bonding and π–π
interactions. In a laboratory test, humic acid alone
yielded 57 % irreversibly bound carbon after a standard
hydraulic rinse. In contrast, the inclusion of nonionic
surfactants reduced that fraction to 20 % and
maintained operating pressure between 83 and 105 kPa
(Kallapalli & Basu, 2025). A combined humic-protein-
alginate mixture at only 50 mg/L lowered flux by 21.7 %,
and in the presence of 0.5 mM Mn²⁺ accelerated
permeability decline to 66.8 % due to the formation of
dense organo-mineral co-aggregates, as shown in Figure
1 (Gao et al., 2023).
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Fig. 1. Effect of different Mn2+ concentrations on RO membrane fouling caused by HBS (Gao et al., 2023)
This effect is most pronounced at neutral pH and high
Ca²⁺ concentration since these ions are complex with
NOM oxygen groups, promoting layer compaction.
Biofouling begins with the colonization of the adsorbed
organic film, leading to the exponential growth of an
exopolysaccharide matrix that obstructs feed channels
and impairs shear cleaning. Global expenditures for the
prevention and remediation of biofouling in desalination
are estimated to be approximately $ 15 billion per year.
Industrial lines reach the cleaning threshold, and TMP
increases within 6
–
10 weeks, underscoring the relative
inexpensiveness of timely prevention versus downtime
(Ahmed et al., 2023). According to DuPont FilmTec
guidelines, cleaning should be initiated at a 15 %
increase in hydraulic gradient, lest the biofilm progress
to a dense, mineralized crust that is poorly soluble at
elevated pH (Lakner & Lakner, 2025).
Colloidal fouling is formed by silicates, iron-oxide flocs,
and organo-clay particles ranging from 100 nm to
several micrometers. Their deposition intensifies when
the polyamide surface charge is partially screened by
divalent cations, resulting in reduced dispersion due to
coagulation. On unmodified membranes, a layer of
amorphous silica reduced flux by 53% and left less than
1% reversible fouling after rinsing; modification with
cationic monomers reduced the irreversible fraction to
13
–
33%, highlighting the key role of electrostatic forces
in colloidal cake formation (Lin et al., 2021). Although
colloids generally do not chemically interact with
polyamide, they form a diffusion barrier and provide a
scaffold for subsequent biofilm and crystal growth,
making their early removal an essential element of
comprehensive protection.
Thus, each foulant group has its primary driver:
supersaturation for inorganics, hydrophobic and ionic
interactions for organics, microbial metabolism for
biofouling, and colloidal destabilization for solid-
dispersed particles. Despite their differing natures,
these mechanisms reinforce one another, forming a
hierarchical deposit layer. Effective prevention,
therefore, requires precise identification of the
prevailing foulant type and deployment of targeted
measures before the TMP increase exceeds the
operational threshold. The classification above
establishes the analytical framework for subsequent
sections, which will examine detailed nucleation
mechanisms, growth kinetics, and optimal suppression
strategies for each fouling type.
The active polyamide‐skin surface layer is
the primary
reactive center, and any chemical attack rapidly
translates into performance loss. Among the most
aggressive factors is active chlorine: 50 ppm NaOCl at pH
4 for just 2.5 hours reduced water permeability by
approximately 40% due to hydrogen-bond cleavage and
amide-group chlorination, whereas alkaline treatment
produced only moderate compaction and a slight
increase in selectivity (Verbeke et al., 2020). In addition
to oxidants, Fe²⁺/Cu²⁺ ions catalyze the radical
-driven
crosslinking and hydrolysis of polyamide, and the
sorption
of
surfactant
organics
increases
hydrophobicity, facilitating subsequent inorganic
deposition.
Acid-base conditions fundamentally alter the charge
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architecture of the active layer. At pH ≈ 3–
4, carboxyl
groups are largely
undissociated, and the ζ
-potential is
near zero; at pH 8
–9, it shifts to ≤ –
10 mV, enhancing
electrostatic repulsion of colloids and macro-ions (Pipich
et al., 2021). A comprehensive study showed that the
addition of sticky monocations (Cs⁺ > Na⁺ > Li⁺) o
r
polarizable Cl⁻ ions could partially screen or even invert
the negative surface charge, directly affecting ion
permeation and water flux (Roth et al., 2024), as
illustrated in Figure 2.
Fig. 2. Correlation between membrane zeta potential and ion permeability (Roth et al., 2024)
Divalent Ca²⁺ and Mg²⁺ ions form ionic bridges between
carboxyl groups and promote the layering of organic
acids and humic substances, thereby preparing the
substrate
for
a
mixed
organo-mineral
cake.
Temperature simultaneously accelerates diffusion and
increases the rate constants of crystallization. Under
high cross-flow, this amplifies the concentration
gradient in the boundary layer. In an industrial cell, this
is equivalent to an increase in local salinity at the
membrane surface relative to the bulk, which directly
raises the osmotic pressure and consumes net driving
pressure, accelerating the transition from concentration
polarization to actual salt scaling.
When the surface concentration reaches the product-
critical threshold, nucleation processes commence. For
CaSO₄ at a saturation index up to 3.0, the induction
period in a continuously stirred solution was 150
–
270
min; periodic flow reversal was sufficient to reset the
induction time and completely suppress precipitation
for up to 8 h (Pomerantz et al., 2006). Once
crystallization begins, permeability declines in an
avalanche-like manner: laboratory tests revealed that
flux-versus-time curves at varying Reynolds numbers
and temperatures converge toward a critical flux.
Increasing temperature accelerates the growth of
acicular
gypsum
crystals,
thereby
increasing
hydrodynamic resistance and deposit mass (R² ≥ 0.97
between deposit mass and T) (Ashfaq et al., 2019).
Under pH-dependent reductions in carbonate solubility,
a similar pattern emerges at even lower saturation
indices
—local pH rises due to CO₂ degassing in the outer,
dehydrated layers are sufficient to trigger scale
formation.
Thus, chemical modifications of the active layer, changes
in its charge, and surface energy induced by pH and ionic
composition, together with kinetic effects of
temperature and concentration polarization, mutually
reinforce one another and set the initial conditions for
crystallization.
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The bacterial load in feedwater is rarely sterile. Analysis
of 150 autopsied industrial modules revealed that at just
10,000 CFU·cm⁻² on the membrane surface, the system
enters the problematic category according to biofouling
indicators. A concentration of 1000 CFU·
mL⁻¹ in the
concentrate reliably correlates with an accelerated rise
in transmembrane pressure (Kucera, 2019). For rapid
online control, bacterial growth potential via ATP is
increasingly employed: at a full-scale SWRO plant,
raising the BGP in the feed fr
om 100 to 950 µg C·L⁻¹ led
to a monotonic increase in normalized ΔP and a parallel
decrease in permeability over three months of
operation, confirming the metric’s predictive value
(Abushaban et al., 2020). Such biological nutrient load of
the feed stream determines the initial colonization of
the fresh polyamide surface, whose properties by that
time have already been altered by the pH- and ion-
induced charge shifts described above.
The first stage of biofilm formation involves the
conditioning of an organic film, a coating a few
nanometers thick, which neutralizes the membrane’s
native hydrophilicity and provides sites for the
reversible electrostatic adsorption of bacteria. Modeling
aligned with nutrient-profile data indicates that, given
an easily assimilable substrate, biofilm thickness near
the inlet of an element reaches ≈ 200 µm by day 20. In
contrast, at the outlet, it remains around 1 µm
—
this
gradient reflects nutrient depletion along the channel,
as illustrated in Figure 3 (Hoek et al., 2022).
Fig. 3. Model illustration of local substrate-limited biofilm growth kinetics and biofilm thickness (Hoek et al.,
2022)
Exponential growth is accompanied by the incorporation
of Ca²⁺ and Mg²⁺ into the
EPS matrix, creating a porous
micro-reactor within which pH and ionic strength
deviate from bulk values, further promoting local scaling
and cementation of the biofilm.
A direct consequence of these processes is increased
hydraulic resistance. In membrane simulators,
increasing the load by 100
–
400 µg C/L (as acetate
equivalent) accelerated biomass accumulation. It
caused ΔP to grow by 0.2 bar over 7 days, whereas
lowering the substrate load slowed the trend and
allowed reversible ΔP reduction by merely decr
easing
the cross-flow velocity (Vrouwenvelder et al., 2009).
Biofilm accumulation also alters flow distribution.
Computational analysis has shown a shift in the peak flux
from leading elements toward the tail due to a decline
in inlet TMP and the forced redistribution of load, which
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induces additional internal polarization (Hoek et al.,
2022). Beyond purely hydraulic losses, microbial
metabolic activity affects selectivity: acidic and
amylolytic enzymes, as well as free chlorine generated
within the biofilm, can increase water permeability by
up to 70 % while simultaneously linearly reducing salt
rejection, indicating degradation of the polyamide
matrix (Kucera, 2019).
Thus, biofouling unites the trigger aspects of chemistry
and
hydrodynamics
—
nutrient
micro-pulses,
electrostatic
screening,
and
concentration
polarization
—
forming a self-sustaining layer that not
only physically blocks channels but chemically ages the
active composite. It is precisely at this intersection that
the key intervention points lie, and these are discussed
further in the section on preventive strategies.
The reliable operation of RO trains begins with precise
monitoring of primary fouling markers. Spiral-wound
module manufacturers recommend initiating cleaning
as soon as the normalized
ΔP increases noticeably, the
permeate flux drops measurably, or the salt passage
rises relative to the startup values. These three
parameters
—
a module pressure drop, normalized flux,
and salt passage
—
remain the foundation of daily
monitoring, as they can be temperature-corrected and
restored to baseline after cleaning, thereby objectively
assessing membrane fatigue and the effectiveness of
the cleaning process.
Hydraulic indicators detect an already established layer,
whereas biological signals respond earlier. Flow
cytometry and ATP sensors detect viable-cell growth
long before a notable ΔP rise, and a monotonic increase
in permeate bacterial potential reliably predicts
subsequent growth in channel resistance. Such early
warning affords the operator time for rapid disinfection
or
antifoulant-dosing
adjustment,
preventing
unplanned shutdowns.
When membranes are finally opened, a vast arsenal of
autopsy techniques is applied. SEM-EDS locates
crystallization centers even within multilayer organo-
mineral
crusts,
while
infrared
spectroscopy
distinguishes humates and polysaccharides in the
biofilm. Combined with confocal tomography, these
methods yield a three-dimensional map of layer
thickness and porosity, serving as the basis for validating
hydrodynamic polarization models.
Diagnostic data forms the architecture of prevention.
The first barrier is deep pretreatment, which involves
coagulation with iron or aluminum salts to aggregate
particles, shift their charge into the near-neutral range,
and markedly reduce th
e ΔP rise compared to cartridge
filtration alone. When combined with ultrafiltration,
only traces of colloids larger than the micron range
remain in the feed, significantly reducing the likelihood
of early colloidal-cake formation and delivering energy
savings through lower operating pressure.
For the control of inorganic scaling, antiscalants
—
phosphonates and acrylic copolymers
—
play a key role
by suppressing gypsum and calcite nucleation across
operating saturation‐index ranges. In contrast,
optimized dosing control extends the cleaning interval
several-fold. Concurrent mild acidification reduces
carbonate‐ion activity, further decreasing crystallization
rates and lowering inhibitor consumption without
compromising recovery.
Biofouling is countered in two stages: first, by
dechlorination with excess metabisulfite, and then by
periodic pulses of a non-oxidizing biocide. This scheme
maintains ΔP within the operating corridor and permits
significantly longer intervals between complete clean‐
in‐place cycles than
standard schedules.
The growth of operational data volume has enabled
automated
regime
optimization.
Deep-learning
algorithms, trained on flux, pressure drop, and salt
passage variations, already demonstrate the ability to
select feed pressure and recovery to sustain near-
complete salt rejection at minimal energy consumption,
while simultaneously postponing CIP dates. When
coupled with digital biological-activity sensors, these
controllers transform diagnostics into a closed-loop
control system in which any detected anomaly
automatically triggers adjustments to flow, pH, or
chemical dosing.
The synergy of real-time indicators, advanced analytics,
and adaptive control underpins the longevity of
membrane systems. The earlier a deviation is
detected
—
whether a
jump in ΔP, a spike in biological
activity, or a change in spectral signature
—
the gentler
and cheaper the corrective action. By unifying fine
pretreatment, targeted reagents, biological monitoring,
and machine optimization into a single cycle, operators
achieve stable permeability and a predictable cost per
cubic meter of produced water
—
the ultimate goal of a
fouling-prevention strategy.
Thus, the comprehensive analysis of reverse‐osmosis
fouling mechanisms demonstrates that the key to
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stable, economical membrane operation lies in
sequential implementation of integrated preventive
measures: from deep pretreatment and pinpoint
chemical protection to online monitoring of hydraulic
and biological markers, followed by adaptive control of
wash cycles and reagent dosing. Only by accounting for
the interdependence of carbonate, organic, colloidal,
and biological fouling
—
as well as the influence of pH,
ionic composition, and temperature
—
can the operating
strategy be adjusted in time to minimize irreversible
deposits and extend maintenance intervals. This holistic
combination of diagnostics, targeted chemistry, and
intelligent control lays a robust foundation for further
development of membrane systems. It guides the final
recommendations for optimizing and enhancing the
cleaning process and improving water security.
Conclusion
The comprehensive analysis of physicochemical and
biological fouling mechanisms in reverse‐osmosis
membranes has revealed that the primary drivers of
deposit formation and development are local
supersaturation of salt components, hydrophobic and
ionic interactions of organic substances, microbial
metabolic activity, and colloidal instability. Each foulant
type
—
carbonate and sulfate scaling, organic fouling,
biofilm formation, and colloidal cake
—
contributes to
hydraulic-regime degradation, including reduced
permeability, increased transmembrane pressure, and
accelerated deterioration of the polyamide active
surface. Moreover, interactions among foulant groups
amplify one another, creating a hierarch
ical, hard‐to‐
remove cake, which necessitates early diagnosis of the
predominant foulant type before TMP reaches critical
levels or permeate flux declines significantly.
Modern fouling-diagnosis methods, including SEM-EDS,
ATR-FTIR, XPS, and especially optical coherence
tomography, enable real-time tracking of deposit
thickness and morphology without module disassembly.
Combining these tools with online sensors for pressure
drop, normalized flux, and biological markers (ATP
analysis, BGP) generates the rich experimental database
required for both empirical correlations and the
development of mechanistic models and machine‐‐
learning algorithms. This approach provides early
warning of abnormal events and enables rapid
adjustment of operating parameters, thereby markedly
improving forecast accuracy and the efficacy of
preventive interventions.
The practical implementation of preventive strategies is
built upon the integration of deep pretreatment
(coagulation,
microfiltration,
and
controlled
chloramination),
targeted
chemical
reagents
(phosphonates, acrylic copolymers, non-oxidizing
biocides, and photocatalysts), and adaptive control of
cleaning and flow regimes. A cascade combination of
fine physicochemical feed preparation with gentle
biocidal measures suppresses organic and biological
fouling without damaging the polyamide layer.
Antifouling
surface
coatings
and
shear-rate
management, combined with deep-learning algorithms
for automatic adjustment of pressure, reagent doses,
and recovery, create a closed control loop that unites
diagnostics, response, and real-time performance
analysis.
Consequently, a systematic approach
—
from precise
identification of the dominant foulant type to adaptive
control and intelligent optimization
—
emerges as the
key factor in extending membrane life and reducing the
cost per cubic meter of produced water. The sequential
integration of diagnostic technologies, targeted cleaning
chemistry, and machine‐‐driven operation control
ensures stable permeability, predictable operating
expenses, and minimization of irreversible deposits.
Such a comprehensive suite of measures provides a solid
foundation for future engineering optimizations of
membrane systems and enhanced water security.
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