Process Description
The flash chamber is designed to promote
complete dispersion of the injected polymer throughout the chamber.
Complete dispersion assures intimate contact of the polymer with the
small coagulated particles. Performing this
basic process will improve overall treatment quality and reduce overall
chemical consumption.
The flocculation tank gently mixes the contents, allowing the
flocculated particles to grow in both volume and mass, allowing
easy removal by downstream clarification equipment
(sedimentation or floatation).
The Equipment:
The basic system is
comprised of a dual compartment flash mix flocculation tank, a flash
mixer, a variable speed floc mixer, a polymer injection system
(featuring either an automatic poly makeup system or a manual day
tank setup),
and a
control panel.
Skid:
A steel skid is provided for supporting the
entire system. The skid features a welded 4" steel "C" channel
frame, and a 1/4" steel deck plate. The entire skid is blasted to an
SSPC-SP6, and coated with a 2 part self priming epoxy finish for
corrosion resistance. The skid color is OSHA Safety Blue,
unless otherwise specified.
Optional Containment Pan: As an
option, a containment / drip pan can be provided for protecting
the steel skid from leaking or spilled corrosive fluids. A drain
connection is provided for plumbing the containment pan to a
suitable location. The pan can be fabricated from polypropylene,
stainless steel, etc. and features 8" high walls.
The Reaction Tank:
When designing the reaction tank, size and
materials of construction are the primary consideration.
Typically, the tanks are sized for approximately 30
seconds of flash mix capacity and 3 minutes of floc residence time.
These basic guidelines will vary based on the chemistry employed at
your facility.
Material of construction is typically epoxy
coated carbon steel, but
we can
fabricate the system from any commercially available material
including polypropylene,
stainless steel, FRP, exotic alloys and all thermoplastics.
Hydro-Flo addresses these items, as well as others, in order to properly size the
system and choose the correct materials of construction for the
application.
Reagent Storage Tanks:
Chemicals for treatment are pumped directly
from 55 gallon DOT drums. An alternate to pumping directly
from DOT drums is utilization of day tanks, which can be
automatically refilled from the customer's bulk chemical delivery system
within the plant. Redundant level sensors and redundant fill valves
provide protection against overfilling.
Valves:
All ball valves are true union, field
serviceable valves. All diaphragm valves are flange mounted. Elastomers are EPDM and Teflon, except on concentrated acid lines
where the elastomers are Viton and / or Teflon.
Plumbing:
All recirculation, transfer and discharge
lines are fabricated from solvent welded, PVC SCH 80 pipe. All
reagent delivery lines are flexible, PFA tube double contained within
a clear flexible PVC hose, clamped at each end to seal leaks.
The Mixers:
The mixers are one of the
key elements of the system. The system will not generate
consistent results without properly designed mixers.
The flash mixer is typically a direct drive,
continuous output device, but variable speed can be included as an
option.
The floc mixer is typically a gear reduced, low
RPM variable speed device.
Chemical Metering Pumps:
Properly sizing the
chemical metering pumps is important in order to achieve the correct
chemical reactions. Also, metering pump sizing has an impact
on total chemical consumption. Properly sized pumps will help
you reduce overall chemical costs.
Control Package:
Control packages (depending on your specific requirements) are
available in either basic relay logic controls, or a full state of the art
PLC
with touch screen HMI and our
sophisticated treatment algorithms. The relay logic controls
package allows basic reconfiguration of the original system settings,
while the PLC based package allows maximum flexibility
to change the process parameters as well as tight control that
minimizes chemical usage. We can include a variety of options
including digital data logging of critical
process parameters, ethernet access to process data, communication
with Building Management Systems, and even remote system access
using cellular wireless technology.
All enclosures are NEMA 4X. Where metallic
enclosures are used, they are provided with epoxy or polyester
finishes for corrosion resistance. All conduit is plastic coated,
where possible. Low voltage 24VDC is used throughout to minimize
service personnel exposure to high voltage. All panels are OSHA LOTO
and NFPA 79 compliant. UL-508 listing is available.
System Packaging:
The system is supplied as a completely
fabricated "turnkey" package. All devices are pre-wired and plumbed.
You need to make the plumbing connections to
and from the system and a single electrical connection point for
incoming power. The disconnect on the MCP provides OSHA Lock
Out / Tag Out and NFPA 79 compliance. LSystems requiring
compressed air, also require only one connection and the valve is
supplied for OSHA LOTO.
Additional Information
For specific equipment information, contact us
directly. We can provide the specifying engineer with a formatted
specification package that thoroughly describes any of our systems
for bidding purposes. This includes detailed drawings, and detailed
equipment specifications.
Flash
mix and flocculation refer to the process by which fine
particulates are caused to clump together into larger "flocculated"
particles. The floc may then float to the top of the liquid, settle
to the bottom of the liquid or, depending on it's characteristics,
remain suspended. Depending on the results, the solids can be
separated by the use of a sedimentation clarifier, a flotation
system or filtration system.