PART 1 - GENERAL
1.1 Scope: The work covered in this section includes furnishing
all labor, material, equipment and incidents to install
complete and ready for operation, a polymer feed system
device as shown on drawings and as specified herein.
1.2 APPLICABLE PUBLICATIONS: The publications listed below
form a part of this specification to the extent referenced.
The publications are referred to in the text by the basic
designation only.
American National Standards Institute (ANSI) Publication:
Pipe Flanges and Flanged Fittings, Class 25, 125, 250 and
800
American Society for Testing and Materials (ASTM) Publications:
ASTM D 1785 Polyvinyl Chloride (PVC) Plastic Pipe, Schedules
40, 80, and 120
A-240 304L Stainless Steel Plate
A-249 Stainless Tubing
A-276 304L Stainless Rounds, Squares, Flats
1.3 SUBMITTALS:
1.3.1 Contracting officer will review and approve all submittals.
1.3.2. Submit the following before fabrication
1.3.2.1 Shop Drawings: Shop drawings for polymer feed system
and accessory equipment including principle dimensions and
location of fittings.
1.3.2.2 Calculations to prove that the mixing turbulence
is at least G=10,000 sec-1 as well as calculations
to prove that the aging chamber is non-turbulent and not
mechanically agitated.
1.3.2.3 Calculations to prove the mechanical mixing section
does not exceed 30 seconds plug flow at a flow rate of 1.5
gallons per minute.
1.3.2.4 Calculations to prove that the non-turbulent aging
chamber has a plug flow retention time of 10 minutes at
a flow rate of 1.5 gallons per minute.
1.3.2.5 Design details proving the diluted polymer is not
subjected to mechanical agitation after leaving the initial
high turbulent mixing section.
1.4 DELIVERY, STORAGE, AND HANDLING MATERIALS:
1.4.1 Delivery and Storage: Inspect materials delivered
to site for damage; unload and store with minimum handling.
Store materials on site in enclosures or under protective
coverings. Protect materials not suitable for outdoor storage
to prevent damage during periods of inclement weather, including
subfreezing temperatures, precipitation, and high winds.
Store materials susceptible to deterioration by direct sunlight
under cover and avoid damage due to high temperatures. Do
not store materials on ground. Store and protect materials
according to manufacturer recommendations.
1.4.2 Handling: Handle polymer feed system in such a manner
as to ensure delivery to final location in sound, undamaged
condition. Take special care not to damage surfaces of the
polymer feed system. Make satisfactory repairs to damaged
material(s) at no cost. Carry and do not drag materials.
Handle polymer feed system according to manufacturers information.
1.5 QUALITY ASSURANCE:
1.5.1 Inspection: Examine each component of polymer feed
system for compliance with requirements specified. Redesign
or modification of equipment to comply with specified requirements,
or necessary redesign or modification following failure
to meet specified requirements, shall receive particular
attention for adequacy and suitability. This element of
inspection shall encompass visual examinations and dimensional
measurements. Noncompliance with specified requirements,
or presence of one or more defects preventing or lessening
maximum efficiency of polymer feed system operation, shall
constitute cause for rejection.
PART 2 - POLYMER FEED SYSTEM DESIGN CRITERIA
AND MANUFACTURING SPECIFICATIONS
2.1 POLYMER FEED SYSTEM - APPLICATIONS & PERFORMANCE
2.1.1 Applications: The automated polymer dilution/feed
system shall consist of an integrated equipment package
capable of automatically metering, diluting, aging, activating,
and pumping liquid polymer and water. After leaving the
initial mixing chamber, the polymer solution shall pass
through a non turbulent aging chamber. After initial dilution,
the dispersed polymer in water shall not be subjected to
shear.
2.1.2 Performance: The system shall have the capability
of handling emulsion and solution polyelectrolytes. The
system shall be designed to mix a 20 - 50 percent concentrated
liquid polymer solution with viscosities up to 60,000 CPS
with water, automatically produce a diluted and aged polymer
solution and to convey the aged polymer solution to the
application point. The system shall be an integrated package,
prepiped, and prewired. The configuration shall provide
for a complete integral polymer feed system, mixing and
aging the polymer, and occupying the smallest possible space.
The feed system input range shall be up to A*
USGPH dilution water and up to B*
USGPH polymer.
2.2 POLYMER FEED SYSTEM - Manufacturing specification
2.2.1 Mixing Requirements: Mixing energy shall be provided
by a motor driven stainless steel multi-bladed impeller.
Mixing chamber impeller shall be powered by a heavy duty
direct drive 1725 rpm motor of at least 3/4 HP with manually
resettable thermal overload protection; belt drives and
static mixers shall not be acceptable. Impeller shall rotate
on a stainless steel shaft supported by stainless steel
bearings and seals. Mixing chamber shall be transparent
acrylic and shall be capable of 100 psig working pressure.
To prevent vortexing and induce uniform back mixing throughout,
the mixing chamber shall contain at least four (4) stainless
steel baffles rigidly mounted near the mixing chamber’s
internal wall.
The polymer mixing/dilution chamber shall provide high
speed high turbulent mixing conditions for a short period
to rapidly disperse the polymer, then to prohibit the destruction
of the fragile long chained freshly activated polymer, the
polymer solution shall not be subjected to mechanical agitation
in the aging chamber.
Per the Camp-Steen equation, the mixing chamber will have
a minimum turbulence of G=10,000 sec-1.
The retention time in the mixing chamber shall not exceed
30 seconds at a flow rate of 1.5 gallons per minute.
Polymer mixing system shall be specifically designed to
invert, disperse, age, and activate solution, emulsion and
dispersion polymers with viscosities from 200 - 60,000 CPS.
2.2.2 Aging Chamber: A non-turbulent aging chamber shall
form the base of the polymer mixing device with the high
turbulent mixing chamber integrally attached to the top
of the aging chamber. The aging chamber shall not be subjected
to any mechanical agitation and shall be of non-metallic
construction. The aging chamber shall have PVC internal
baffles to prohibit channeling or short circuit flows.
The aging chamber shall provide a retention time of at
least 10 minutes at a flow rate of 1.5 gallons per minute.
2.2.3 Water Flow: The system shall have a switch to shut
power off to the unit in case of low water pressure, an
electrically operated solenoid valve for on/off control
of dilution water supply, and a rotameter type indicator
equipped with an integral rate adjusting valve. The flow
indicator shall have a valve stop and guided float. Water
flow rate shall be adjustable to A*
USGPH. Water supply input shall be C*
" FNPT and stock solution outlet fitting shall be D*
" FNPT. Polymer feed system shall be capable of operating
with a water supply pressure of 30 PSIG.
2.2.4 Controls and Metering Pump: Components shall include
but not be limited to: solenoid valve and rotameter with
rate valve on water; water pressure regulator, and metering
pump.
Metering pump shall have a variable stroke rate and stroke
length. Output volume shall be adjustable while pump is
in operation.
Metering pump shall be of the electronic solenoid operated
type. Pump shall be positive displacement with no mechanical
linkage. Power supply will be 115 volt, 60 Hz.
OPTIONAL 2.2.5 (Slave Pump) Metering Pump 4-20 mA Controllable:
Metering pump shall be upgraded to a model that is controllable
by means of either a 4 - 20 mA signal or manual control
to automatically proportion the polymer.
OPTIONAL 2.2.6 (Smart Pump) Low Flow Shutoff Switch: A
low flow shutoff switch is available as a replacement to
the standard low pressure shutoff switch. This option would
be useful should the solution flow exiting the polymer system
be blocked (by a valve down stream being in the wrong position).
OPTIONAL 2.2.7 Calibration Tube Assembly: The calibration
tube assembly is an 8 oz. tube mounted to the side of the
aging chamber that tees into the polymer line leading to
the metering pump. The standpipe shall allow convenient
observation of maximum speed settings. The tube is used
to isolate a precise amount of polymer (8 oz.), allowing
for observation of seconds elapsed during use of the precise
amount. With this information, the operator can calculate
gph of polymer use and, with knowledge of the wastewater
stream flow, can also calculate dosage in ppm.
2.3 CONTROL PANEL
2.3.1 Central Controls: The central controls shall be housed
in a NEMA 4 enclosure. Controls requiring operator adjustment
shall be surface mounted. Control panel shall be mounted
on the polymer mixing and aging unit.
2.4 TESTING
2.4.1 The entire unit shall be shop hydrostatically tested.
Documentation of hydrostatic test shall be provided.
PART 3 - DELIVERY, STORAGE AND HANDLING MATERIALS
3.1 Delivery and Storage: Inspect materials delivered to
site for damage; unload and store with minimum handling.
Store materials on-site in enclosures or under protective
coverings. Protect materials not suitable for outdoor storage
to prevent damage during periods of inclement weather, including
subfreezing temperatures, precipitation and high winds.
Store material susceptible to deterioration by direct sunlight
under cover and avoid damage due to high temperatures. Do
not store materials directly on ground. If special precautions
are required, prominently and legibly stencil instruction
for such precautions on outside of equipment or its crating.
Store and protect materials according to manufacturers recommendations.
3.2 Handling: Handle polymer feed system in such a manner
as to ensure delivery to final location in sound, undamaged
condition. Take special care not to damage surfaces of polymer
feed system. Make satisfactory repairs to damaged material(s)
at no cost. Carry and do not drag materials. Handle polymer
feed system according to manufacturers information.
PART 4 - EXECUTION
4.1 Installation: Polymer feed system to be installed as
indicated and as recommended by the manufacturer. Equipment
delivered to the site in advance of installation to be stored
per the manufacturer’s requirements. Make all connections
as required to make polymer feed system fully operational.
PART 5 - SUGGESTED MANUFACTURER:
The polymer feed system shall be model number # *
manufactured by:
Hoffland Environmental, Inc.
10391 Silver Springs Road
Conroe, Texas 77303-1602
(936) 856-4515 phone / (936) 856-4589 fax
e-mail: hoffland@flex.net
*Model Number *
| Model No. |
Dilution
GPH
"A" |
Polymer
GPH
"B" |
Inlet
"
"C" |
Outlet
"
"D" |
| PM-100-0.2 |
100 |
0.2 |
1/2 |
1 |
| PM-100-1.0 |
100 |
1.0 |
1/2 |
1 |
| PM-300-1.0 |
300 |
1.0 |
1/2 |
1 |
| PM-300-1.0 |
300 |
1.0 |
1/2 |
1 |
| PM-600-1.0 |
600 |
1.0 |
1 |
1 |
| PM-600-1.83 |
600 |
1.83 |
1 |
1 |
| PM-600-5.0 |
600 |
5.0 |
1 |
1 |
| PM-1200-5.0 |
1200 |
5.0 |
1 |
1 |
| PM-1200-9.0 |
1200 |
9.0 |
1 |
1 |
|
