High-Quality
Control
Disodium
Hydrogen
Phosphate
(Na2HPO4)
MEE
Evaporation
&
Vacuum
Crystallization
Line
Engineered
multi-effect
falling/thin-film
evaporation
with
integrated
vacuum
crystallization
to
produce
high-purity
Disodium
Hydrogen
Phosphate
crystals
with
consistent
particle
size,
low
moisture,
and
reliable
batch-to-batch
quality.
Optimized
steam
economy,
compact
footprint,
and
full
PLC
automation
make
it
ideal
for
fine
chemicals
and
food/pharma-adjacent
applications.
Tight
Quality
Control
Online
density/conductivity,
mother-liquor
recycle
logic,
and
crystal-size
control
(saturation
curve
&
residence
time)
to
meet
specification
consistently.
Steam
Economy
Each
effect
reuses
vapor
from
the
previous
effect
as
the
heating
medium;
optional
TVR/MVR
modules
further
cut
utilities.
Clean
Operation
Vacuum,
low-temperature
evaporation
minimizes
product
degradation;
mirror-polished
tubes
reduce
scaling
and
simplify
CIP.
Process
Description
-
Feed
Preparation:
Filtered
Na2HPO4
solution
is
metered
to
the
pre-heater
and
first
effect.
-
Multi-Effect
Evaporation
(MEE):
Falling-film
evaporation
across
2–4
effects.
First
effect
uses
live
steam;
subsequent
effects
use
secondary
vapor
as
heating
media.
-
Vacuum
Crystallization:
Concentrated
liquor
flashes/ages
under
vacuum
to
the
selected
supersaturation;
crystal
seeds
can
be
dosed
to
tune
PSD.
-
Solid–Liquid
Separation:
Crystals
are
discharged
to
centrifuge/pressure
filter;
mother
liquor
is
recycled
to
the
effects
for
yield
improvement.
-
Drying
&
Packaging:
Low-temperature
drying
to
target
LOD;
screened
and
packed
per
specification.
System
Structure
Effects
(heaters
&
separators),
pre-heaters,
vacuum
crystallizer,
condenser
&
vacuum
set,
feed/circulation/discharge/condensate
pumps,
crystal-handling
unit
(seed
tank,
centrifuge),
CIP
skid,
and
complete
instrumentation
(T/P/vacuum/flow/level/cond.).
Key
Features
-
Capacity:
500
kg/h
–
80
t/h
water
evaporation.
-
Materials:
SS304
/
SS316L
(others
on
request).
-
Low-temperature
operation:
Gentle
vacuum
evaporation
limits
hydrolysis
and
discoloration.
-
High
concentration
ratio:
Falling-film
hydrodynamics
handle
viscous
brines
with
short
residence
time.
-
Automation:
PLC/HMI
with
recipe
&
historian;
interlocks
for
vacuum/level/temperature.
-
CIP
friendly:
Seamless,
mirror-polished
tubes
simplify
cleaning
and
mitigate
scaling.
-
Flexible
integration:
TVR/MVR
add-ons,
mother-liquor
recycle,
optional
seed
dosing
and
crystal
classification.
Typical
Three-Effect
Falling
Film
—
Illustrative
Specifications
|
Parameter
|
Unit
|
Value
(Example)
|
|
Evaporation
capacity
|
kg/h
|
3,000
–
50,000
|
|
Raw
steam
consumption
|
kg/h
|
~30–40%
of
single-effect
(e.g.,
900
kg/h
@
3,000
kg/h
duty)
|
|
Evaporation
temperature
(1st
/
2nd
/
3rd)
|
°C
|
~99
/
76
/
53
(vacuum)
|
|
Steam
pressure
for
1st
effect
|
MPa
(abs)
|
0.6
–
1.0
|
|
Feed
solids
(Na2HPO4)
|
%
w/w
|
8
–
12
(typical)
|
|
Crystallizer
outlet
|
—
|
Target
supersaturation
per
grade;
mother-liquor
recycle
|
Quality
&
Compliance
-
Process
analytics:
density/conductivity,
temperature,
vacuum,
and
flow
trending
for
batch
traceability.
-
Welds
&
pressure
parts
to
applicable
standards;
material
certificates
available.
-
Validation
support
for
cleaning
and
product
changeover
where
required.
Delivery
Workflow
Feed
&
target
→
Lab/pilot
(optional)
→
Process
&
heat
balance
→
Detailed
engineering
&
fabrication
→
Installation
&
commissioning
→
Performance
test
&
training
→
O&M
support.
