Product Specifications for
Brentwood CFS-3000 Cross Flow Media
DIVISION 11 - EQUIPMENT
Section 113__ - Trickling Filter Media System
A. Installation of trickling filter media support
system, PVC structured sheet media modules and protective surface
grating, as shown on drawings and as specified herein.
1.02 REFERENCE STANDARDS
A. ASTM - American Society for Testing and Materials
B. AISC Code of Standard Practice
C. PCI - Prestressed Concrete Institute
1. Media Support System - Structural system designed and supplied
by Trickling Filter Media System manufacturer to support Structured
PVC Media Modules while maximizing ventilation and drainage. Support
system to be pre-engineered PVC/glass-reinforced ABS piers supporting
pultruded fiberglass grating, or alternatively reinforced concrete
piers and pre-cast, pre-stressed concrete lintels.
2. Structured PVC Media Modules - Media modules are fabricated
from PVC sheets and completely corrugated at an angle of 60 degrees
from the horizontal to form a cross-corrugated pattern between adjacent
sheets, creating a continuous and horizontal redistribution of air
and wastewater. Modules will be either 1 ft. (0.305 m) or 2 ft. (0.610
m) high, 2 ft. (0.610 m) wide, and either 4 ft. (1.219 m) or 6 ft.
(1.829 m) long.
3. Protective Surface Grating - Interlocking polypropylene
panels, a minimum 1-1/4 in. (31.75 mm) height, to absorb hydraulic
impact, provide operator access, provide a protective layer from foot
traffic, and added UV protection to the top layer of Structured PVC
Media Modules. Alternatively, fiberglass grating of similar height
and similar opening size may be substituted.
B. Description of Trickling Filter Media System:
1. System shall provide for the following requirements:
a. Number of Towers: ____
b. Tower Diameter: ____ ft.
c. Depth of Media: ____ ft.
d. Volume of Media Required: ____ cu. ft. (including provisions
2. System includes Media Support System, Structured PVC Media Modules
and Protective Surface Grating.
C. Interface with Adjacent System(s):
1. Install Trickling Filter Media System within the Trickling Filter
tower as recommended by Trickling Filter Media System manufacturer,
or as directed on project drawings. System to be installed in coordination
with Rotary Distributor System work.
1. Media Support System shall be installed true level, plus or minus
__ in. (13 mm) in height.
2. Structured PVC Media Modules shall be constructed to ensure that
solvent bond points are within __ in. (13 mm) from the top and bottom
of the modules on all sheets.
3. Structured PVC Media Modules tolerances for height, width and
length shall be plus or minus __ in. (13 mm) for each dimension (tolerances
may vary by sheet thickness).
4. A maximum of 2-in. (50 mm) is allowed during installation between
the field-cut edges of the Structured PVC Media Modules and the tank
perimeter wall and the center column.
5. The top of the Media Support System and the top of the support
ledge (as specified in Section 3.02 H) should be at the same elevation
and within a maximum tolerance of plus or minus 1/8 in. (3.18mm) in
E. Performance Requirements:
1. Media Support System:
a. Media Support System shall be designed and pre engineered to
support the design load (40 lbs. / sq. ft. per ft. of media (195.3
kgs / m__ per 0.3 m)) of Structured PVC Media Modules. The Media
Support System must allow for field adjustments to meet height tolerances,
and be readily adjustable to allow for variations in floor slope
to ensure vertical alignment of piers. Concrete piers must provide
adequate re-bar reinforcement and the pre-cast, pre-stressed concrete
lintels must be engineered to meet the load requirements and shall
be installed with lintels at a maximum of 2-ft. (0.610 m) center-to-center
spacing. Concrete masonry units such as cinder blocks, underdrain
tiles or other such inadequate structural members will not be acceptable.
Similarly, grouting to achieve leveling requirements will not be
acceptable as structural load bearing material, except as necessary
to secure concrete lintels to piers.
b. Media Support System shall be designed and engineered to maximize
ventilation and drainage requirements, while ensuring sufficient
contact with Structured PVC Media Modules such as to prevent media
from wrapping around supports. Pre-engineered pier caps must allow
for drainage and ventilation. Pre-engineered systems shall incorporate
nominal 12-in. (350 mm) wide pultruded fiberglass grating of adequate
strength to meet the design load, while not allowing excessive deflections.
Concrete lintels must be at least 8-in. (200 mm) wide at the lintel/media
interface. Concrete lintels of 10-in. (250 mm) wide must incorporate
a 2-in. (50 mm) center drain channel.
2. Structured PVC Media Modules:
a. Each Structured PVC Media Module shall be 100% cross-flow and
completely corrugated at an angle of 60 degrees from the horizontal
to form a cross-corrugated pattern between adjacent sheets, providing
a continuous and horizontal redistribution of air and wastewater.
The module shall ensure adequate contact and diffusion between liquid,
air and biomass by providing a minimum of 180 mixing or redistribution
points per cu. ft. (6,356 per m3) of module. Random, vertical or
horizontal media are not acceptable.
b. The flute height for each corrugation in the Structured PVC
Media Module shall be 1.20 in. (30.50 mm). There shall be a minimum
of 20 sheets per each 24-in. (0.610 m) wide module.
c. Each Structured PVC Media Module must provide a minimum surface
area of 31 sq. ft. / cu. ft. (101 m_ / m3) with a minimum of 95%
d. Each module shall have a minimum bearing capacity of 400 lbs.
/ sq. ft. (1952.8 kgs. / m?). Modules in the top layer shall have
a minimum bearing capacity of 1000 lbs. / sq. ft. (4882 kgs / m__).
In addition, media modules shall be capable of withstanding a minimum
loading of 40 lbs. / sq. ft. per foot (195.3 kgs / m? per 0.3 m)
of media height above the module as placed in the filter. Media
modules in the bottom layer shall have the designed load bearing
capacity as estimated by the loading of 40 lbs. / sq. ft. per foot
(195.3 kgs / m__ per 0.3 m) of media height or 1000 lbs. / sq. ft.
(4882 kgs / m__), whichever is greater, when placed on media supports.
e. The maximum allowable deflection shall be 1.5 percent at a test
temperature of 75°F (24°C).
f. The finished modules shall be suitable for normal wastewater
temperatures between 50°F and 75°F (10°C and 24°C).
3. Protective Surface Grating:
a. Protective Surface Grating shall be a minimum 1-? in. (31.75
mm) in height for additional top layer UV protection. Additionally,
no greater than a 2 in. by 2 in. (50.80 mm by 50.80 mm) opening
will be allowed for protection from hydraulic impact. Protective
grating must have a non-skid surface. Protective Surface Grating
must not adversely impact or damage media. If fiberglass grating
is selected, cut edges must be properly sealed to prevent damage
to grating and/or operators.
A. Qualifications of Manufacturer:
1. Trickling Filter Media System manufacturer shall certify that
they have a minimum of 10 installations of Structured PVC Media Modules
in wastewater treatment applications, and at least 5 years continuous
experience in manufacture and supply of Structured PVC Media Modules
in wastewater treatment applications.
2. The Media Support System shall be a standard product of the Manufacturer
specifically designed for wastewater applications, and the Trickling
Filter Media System manufacturer shall certify that they have more
than 5 existing Media Support System installations in use in wastewater
treatment applications. Alternatively, an active member of Prestressed
Concrete Institute (PCI) must produce any pre-cast, pre-stressed concrete
lintels in accordance with the PCI Design Handbook and MNL-116, Manual
for Quality Control.
3. The Structured PVC Media Modules shall be a standard product of
the Manufacturer, and the Trickling Filter Media System manufacturer
shall certify that they have the existing installations of the Structured
PVC Media Modules as required in this Section 1.04A.
4. The Protective Surface Grating shall be a standard product of
the Manufacturer specifically designed for wastewater applications,
and the Trickling Filter Media System manufacturer shall certify that
they have more than 5 existing installations of the Protective Surface
Grating, unless fiberglass grating meeting the height and opening
specifications is supplied.
5. Pre-qualification is required for bidding, except for acceptable
manufacturers named herein.
B. Installation Requirements:
1. Install Trickling Filter Media System in accordance with Manufacturer's
2. Trickling Filter Media System manufacturer provides services of
qualified representative onsite to provide instructions on storage,
handling, installation, cutting, etc in accordance with the requirements
of Section 3.03 A.
C. Source Quality Control:
1. All Media Modules shall be formed and assembled in the Manufacturerís
on-going principal manufacturing facility. Assembly in temporary facilities
or field assembly is prohibited.
A. Shop drawings required for following:
1. Media Support System
2. Structured PVC Media Modules
3. Protective Surface Grating
B. Product Data required as follows:
1. Media Support System
b. Installation instructions
2. Structured PVC Media Modules
b. Installation instructions
3. Protective Surface Grating
b. Installation instructions
1. At least 10 days prior to bid, submit to Engineer samples of Media
Support System, Structured PVC Media Modules (2 ft. width x 2 ft.
height by minimum 4 ft. long (0.610 m x 0.610 m x 1.219 m)) and Protective
Surface Grating for any manufacturers to be considered for pre-qualification
to bid. Include with submittal sample 3 copies of complete product
specifications, and written instructions for field cutting and installing
Trickling Filter Media System. Sample to be retained by Owner. Manufacturers
named as acceptable herein are not required to submit samples.
D. Operating and Maintenance (O&M) Instructions:
1. O & M Instructions shall include:
a. Storage and installation procedures
b. Operating instructions
c. Maintenance instructions
1. Provide certificate of compliance with Quality Assurance requirements
of Section 1.04 A and C.
STORAGE & HANDLING
1. Structured PVC Media Modules shall be shipped and delivered to
job site on pallets for ease of handling and to prevent damage.
1. All material and equipment shall be shipped, stored, handled,
and installed in such a manner as to not degrade quality or serviceability.
2. Structured PVC Media Modules shall not be stacked more than 8-ft.
(2.4 m) high (one over the other). All modules shall be stored on
the shipping pallets.
3. All modules shall be stacked such that the PVC sheet planes are
in a vertical position (similar to the manner of their placement inside
4. A light colored cover shall cover all modules required to be stored
in the open beyond two months. Ideally these covers should be double
sided such as a white on black. The white side, facing out, is used
to reflect light away. Clear covers are prohibited. Black is not recommended.
Black will absorb heat and if the cover comes in direct contact with
the media, this heat can be quickly transferred to the media.
5. Covers cannot be wrapped tightly around the media. There should
be at least a 6-in. (150 mm) air gap between the cover and top of
media. The ends of the cover should be securely anchored on all sides
with at least a 12-in. (300 mm) air gap at the bottom. These covers
should provide shading while allowing air to pass through to prevent
heat from building up.
6. Modules should be checked at least once a week. Covers can become
loose over time due to wind or rain and must be re-secured. A check
of the stored area should be done to make any minor repairs to the
cover or to restack any modules that may have fallen.
7. Structured PVC Media Modules exposed to extended non-operational
periods in the tower shall be adequately protected to prevent damage
by temperature and weather conditions.
1. Structured PVC Media Modules shall remain on shipping pallets
until ready to install.
2. Abusive handling of the material shall not be permitted.
3. Structured PVC Media Modules may get brittle at low temperatures
or softer at high temperatures. Therefore, care should be used in
the handling of modules.
1. Install Media Support System.
2. Install Structured PVC Media Modules.
3. Install Protective Surface Grating.
1. Schedule shall be consistent with project completion date and
account for Trickling Filter Media System manufacturer's production
and shipping terms.
ACCEPTABLE MANUFACTURERS, TRICKLING FILTER MEDIA SYSTEM
A. Brentwood Industries, Inc. of Reading, Pennsylvania.
1. AccuPier®Media Support System
2. AccuPac® CF-1900 Cross-Flow Structured PVC Media Modules
3. AccuGrid® BioGrating
B. Approved equal. (Pre-qualification required per Section 1.05 C).
A. Media Support System:
1. The Media Support System stanchion shall be constructed of rigid
2. The Media Support System base and cap shall be constructed of
glass-reinforced ABS to allow the base and cap to be solvent bonded
to the stanchion.
3. Pultruded fiberglass grating shall be used to span from pier to
4. Alternatively, concrete piers and concrete lintels of adequate
structural integrity may be substituted for manufacturer's pre-engineered
system. If concrete piers and lintels are substituted, Trickling Filter
Media System manufacturer is responsible for ensuring adequate structural
integrity consistent with the requirements of Sections 1.03 E 1 a
and 1.04 A 2.
B. Structured PVC Media Modules:
1. The material of construction shall be flame resistant, self-extinguishing,
rigid corrugated PVC sheets that are conducive to biomass and UV protected.
The media modules shall be resistant to rot, fungi, bacteria and inorganic/organic
acids and alkalies as commonly found in municipal wastewater.
2. The PVC sheets shall be of uniform thickness and free from holes,
air bubbles, foreign matter, undispersed raw material or other manufacturing
defects that may adversely affect their performance.
3. The PVC sheets shall be prime, rigid PVC conforming to commercial
standard ASTM D1784:12454B with the following properties.
||gm / cu.cm
||D638 / D882
||D638 / D882
||in. lbs. / mil
||°F (264 psi)
||self-extinguishing < 5 sec.
C. Protective Surface Grating
1. The Protective Surface Grating (BioGrating), when installed per
manufacturer's recommendations shall provide a continuous protective
surface for the Structured PVC Media Modules, minimizing hydraulic
impact on the media, providing additional UV protection, and allowing
operator access to all areas of the tower. Such grating shall comprise
of multiple square mesh of 2 in. x 2 in. (50 mm x 50 mm) openings,
molded together to provide a strong, lightweight panel. Each panel
of the grating will measure about 24 in. (610 mm) in width, 24 in.
(610 mm) in length, 1-? in. (31 mm) in height, and shall weigh approx.
2 lbs. (0.9 kgs).
2. The material of construction shall be rigid polypropylene specifically
UV stabilized for inhibiting UV degradation of the BioGrating under
extended exposure to the sun. The material shall be inert and resistant
to naturally occurring wastewater constituents.
3. BioGrating shall be installed in panels side-by-side and placed
on top of the Structured PVC Media Modules as shown on the manufacturers'
installation drawings. Each panel shall be snapped together with the
adjacent panel with locks at the edges of each panel. The grating
panels shall be placed on top of the media such that the grating is
in contact with the media.
4. The BioGrating shall be designed to prevent damage to the media,
and allow for ease of placement and removal. The BioGrating material
design shall be such that hold down ties, clips or fasteners are not
5. Alternatively, fiberglass grating meeting the requirements of
1. Minimum height of 1-? in. (31 mm) and; 2. A multiple square mesh
of a maximum of 2-in. x 2-in. (50 mm x 50 mm) openings may be used.
Fasteners shall be used with fiberglass grating to lock panels together.
A. Media Support System:
1. The Media Support System shall be comprised of four elements:
the base assembly, the stanchion, the cap and the pultruded fiberglass
2. The base assembly shall be comprised of two interlocking pieces:
a. The base disk shall have indentations in the interior perimeter
to allow ready alignment with the grid pattern marked on the tower
floor. Additionally, the base disk shall have an indentation to
indicate slope when lined up with the base flange.
b. The base flange shall have a broad base providing stability.
The base shall further have pre-drilled locations to allow the base
assembly to be fixed in location and slope using power-driven nails
(nail gun) to the tower floor once alignment and leveling is complete.
c. The base flange shall have percent slope markings on the perimeter
providing for a quick approximation of the slope of the tower floor.
3. The stanchion shall allow for field cutting to length to accommodate
varying stanchion lengths to ensure the entire Media Support System
is installed within elevation tolerances established in Section 1.03
4. The cap shall be specifically designed to support the entire width
of pultruded fiberglass grating, while allowing drainage and ventilation
through the cap.
5. The base assembly, stanchion and cap shall be solvent bonded in
the field after cutting to elevation and leveling complete to provide
a strong, rigid pier.
6. Pultruded fiberglass grating shall be placed on top of the pier
7. Alternatively, concrete piers and concrete lintels of adequate
structural integrity consistent with the requirements of Sections
1.03 E 1 a and 1.04 A 2 may be substituted upon the review and approval
of the Engineer.
B. Structured PVC Media Modules:
1. All PVC sheets shall be thermoformed into corrugated sheets and
have dedicated bond points to allow precise alignment of sheets during
assembly and installation. Non-thermoformed sheets, which do not provide
dedicated bond points for precise sheet alignment, are not acceptable.
2. The self-supporting Structured PVC Media Modules shall be made
from the assembly of the corrugated sheets. These corrugated sheets
shall be solvent bonded together at these dedicated bond points to
give a cross-corrugated pattern, providing a finite number of contact
points thereby forming strong and homogenous media modules. Adhesive
glues shall not be allowed since they may weaken with time. Similarly,
thermal welding of sheets is not acceptable since the bond strength
is inadequate for the rugged structural requirements.
C. Protective Surface Grating:
1. The BioGrating shall be molded in individual units with integral
2. Alternatively, fiberglass grating meeting the requirements of
this Section 11___ may be substituted. Fiberglass grating must be
clipped together using stainless steel clips to prevent separation
when the tower is in operation.
A. Field measurements:
1. Field verify all dimensions affecting installation, particularly
tower diameter. If any discrepancies are found between actual field
measurements and the enclosed drawings, Contractor must notify Engineer
and Trickling Filter Media System supplier immediately.
2. Layout all work prior to installation.
1. Protect adjacent surfaces, piping and other items as may be required.
2. Protect Trickling Filter Media System material as outlined in
Section 1.06 B.
A. Approval for installation or incorporation in this project will
be made only after submittal of shop drawings, or other data as specified
B. The Media Support System shall be installed in accordance with Manufacturer's
recommendations. The tower base shall be cleaned of any debris prior
to proceeding with installation of the Structured PVC Media Modules.
C. The Structured PVC Media Modules shall be installed in accordance
with Manufacturer's recommendations. Media modules shall be conveyed
to the top of the filter wall by mechanical conveyor or crane. Cranes
shall be used or conveyors shall be constructed as necessary to transport
the media to the working level inside the trickling filter, and the
media modules shall be moved by hand for final placement.
D. The media module edges should be protected from damage due to workmen
walking on them. To prevent such damage and to prevent toppling over
of modules in case of cantilever support system, the Contractor shall
use plywood or other suitable temporary planking.
E. The Structured PVC Media Modules shall be carefully cut or trimmed
to fit the tower to within the tolerances specified in Section 1.03
D 4. The shaping, cutting and trimming of the media modules may be done
in the trickling filter provided that precaution is taken by the Contractor
to prevent any chips, broken pieces, or debris from falling into the
media by using canvas tarpaulins or similar working materials to cover
the media modules. All media modules shall be cleared of any such fallen
material before a new layer of media is added. The top layer of media
should also be completely protected from damage and such falling material
due to any subsequent work prior to start up of the system.
F. The media modules shall be placed in the trickling filter to provide
the closest possible fit with adjacent modules without damaging the
modules. The module packing arrangement shall be as recommended by the
media manufacturer and shown on the installation drawings. Media modules
within each layer shall be installed such that the sheets of all modules
are parallel to each other. Modules in respective layers shall be installed
at right angles to the layer immediately below and above.
G. The media modules in the bottom layer shall be placed on the Media
Support System as shown on the installation drawings. A support ledge
(minimum of 4 in. (100 mm) wide) must be provided around the center
column and the tank perimeter wall, and is the responsibility of the
Contractor. Support ledge and Media Support System elevations must meet
the tolerances specified in Section 1.03 D 5.
H. The Protective Surface Grating shall cover the entire media surface
and shall be installed in accordance with Manufacturerís recommendations.
I. After completion of installation of the Trickling Filter Media System,
the Contractor shall submit a written Certificate of Proper Installation
A. Trickling Filter Media System manufacturer shall provide the services
of a qualified field installation supervisor. Such supervision shall
be provided for ___ working days (max.) (not to exceed 8 hrs per day),
and ____ trips (max.) with a maximum stay of 30 days per trip.
A. The Trickling Filter Media System, including Media Support System,
Structured PVC Media Modules and Protective Surface Grating, shall be
guaranteed to be free from defects in material and workmanship for a
period of 1 year from date of Substantial Completion by Owner, or 14
months from date of shipment, whichever is earlier.
A. The Trickling Filter Media System manufacturer shall provide one
structural test (four modules per test) for each different thickness
of Structured PVC Media Modules to be used in the project. The test
shall simulate service conditions and conform to the following criteria:
1. The test sample shall consist of four full-size media modules
stacked two modules high with two modules in each layer. The arrangement
of the stack shall simulate the geometry as placed in the filter towers.
The top modules shall be perpendicular to the bottom modules, and
the PVC sheet planes shall be in a vertical position.
2. Modules intended for the base layer shall be tested on a simulation
of the Media Support System. Modules intended for all other layers
shall be tested on a flat base.
3. Test loads shall be the design load of the media as specified.
The test load shall be at a temperature of 75°F (22.8°C) plus
or minus 2°F (1.2°C).
4. A preload equal to 10% of the design load shall be applied to
act as a seating load. This seating load shall be retained for a 1-hour
5. After 1 hour, the deflection shall be noted and considered zero
and the load increased in 10% increments of the design load. Each
loading increment shall be held for 5 minutes and the deflection recorded
at the end of the 5-minute period. Incremental loading shall continue
6. Maximum allowable deflection at the test load shall be 1.5 percent.
The term "deflection" shall mean the vertical deflection
expressed as percent of the vertical distance between the top and
bottom faces of the media stack under the pre-load conditions.
B. Testing shall be completed in Manufacturers' facilities, and shall
result in a report certified by a Professional Engineer prior to installation
of Structured PVC Media Modules.
C. Trickling Filter Media System manufacturer's with a minimum of 10
installations of Structured PVC Media Modules in wastewater treatment
applications, and at least 10 years continuous experience in manufacture
and supply of Structured PVC Media Modules in wastewater treatment applications
without an incident of Structured PVC Media Modules failure may provide
reports on similar gauge media from prior testing in lieu of testing
of media produced specifically for this project.
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