CHEMICAL FILTER UNIT

PART 1 - GENERAL
1.01 DESCRIPTION

A. This specification covers the procurement, manufacture,

installation and commissioning of package fresh air filter unit
in accordance with the provisions of the system of which these
materials form part.

1.02 CODES AND STANDARDS

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Codes and Standards issued by the listed professional societies
and organizations shall form the reference basis for requirements

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of this project.

A. ASME American Society of Mechanical Engineers Publication

B. ASTM
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American Society for Testing and Materials
Specification
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C. ASHRAE American Society of Heating, Refrigerating and
Air-Conditioning Engineers Publications

D. ARI Air-Conditioning and Refrigeration Institute

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Standards

E. ADC Air Diffusion Council Test Code

F. AMCAAir Moving and Conditioning Association Inc.

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G. NFPANational Fire Protection Association Standards

H. SMACNA Sheet Metal and Air-Conditioning Contractors National

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Association Inc. Publications

I. ARAMCO SAES-K-002

1.03 SUBMITTALS

A. Copies of the following are required to be submitted for review:

1. Detail Drawings and/or Shop Drawings.

2. Quality Assurance.

3. Certificates of Compliance.
4. Test Reports.
 5. Manufacturers Instructions.

6. Operating and Maintenance Manuals.

PART 2 - PRODUCTS
2.01 GENERAL

A. The drawings indicate the extent and general arrangement of the

air conditioning systems requiring package filter unit.

2.02 DESIGN

A. The package fresh air filter unit shall be manufactured to meet

the capacities and dimensions specified on the drawings and/or in

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the equipment schedules and shall fit into the spaces allotted
and shall allow adequate and acceptable clearances for entry,

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servicing and maintenance.

B. The manufacturer shall have a minimum of 5 years of history in

design, fabrication, and testing of similar air purification

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systems. The system shall provide a minimum airflow capacity as
outlined in the specification parameters.
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C. The air purification system shall have filters, chemical media
cells, and final filters to suit the specific requirements.

D. The manufacturer shall guarantee a minimum life expectancy for

the system according to the inlet and outlet contaminant levels
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for this application. Discharge contaminants levels shall not

exceed defined parameters at any time before media expiry.

E. The manufacturer shall have the capability of providing in house

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laboratory analysis for testing media and air samples to assist

in determining media bed consumption rates.
F. Where corrosion control is involved the equipment manufacturer
shall have corrosion monitoring assistance for the controlled
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space. In house production and analysis of corrosion coupons

shall be provided by the equipment manufacturer.

G. The chemical media shall have the capability of being loaded and
unloaded, this shall be accomplished through the removal cells.

2.03 CONSTRUCTION AND FABRICATION

A. The base frame shall be structural steel epoxy coated channel.

B. The unit casing shall be welded with similar metals. Any
dissimilar metals shall be fastened together by mechanical
fasteners.
 C. To produce high quality low distortion welds, the GTAW
(TIG)welding process shall be used.

D. All access doors and hatches shall use closed cell neoprene
gasketing to prevent any air leakage.

E. All gasket material shall be ¼” thick by 0.75” wide closed cell

neoprene foam.

F. Service doors and all unit access shall be oriented to suit field
conditions or requirements.

G. Hinges shall be continuous piano type pin, and constructed of 300

series stainless steel. Doors shall be held closed with quick
release, snap acting type, positive pressure latches.

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H. Any preheating, cooling, or humidification to temper the incoming

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air stream shall be provided by equipment manufacturer.

2.04 PRE-FILTER SECTION

A.

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The pre filter section shall prevent particulates
downstream sections of the air purification system.
into the
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B. The filter section shall include a 40% roughing prefilter, based
on ASHRAE Standard 42.1, and shall carry Class 2 certification
in accordance with UL Standard 900.

C. Filter face velocities and filter resistances shall not exceed

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the allowances for the project.

D. Any mist elimination and grease prefilter systems shall be

provided when required.
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E. Extruded aluminum particulate filter tracks with positive air

seals shall be used to allow easy changing of the filters, and
to ensure air does not bypass the filters.
F. Access doors to the filters shall be with quick release, snap
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acting type, positive pressure latches.

G. The prefilter section shall be monitored by a magnehelic

differential pressure gauge or a photohelic pressure
switch/gauge.

2.05 CHEMICAL MEDIA

A. The chemical media(s) shall be as selected for this application

with minimum performance and physical characteristics as defined
for the application. Media data sheets, current MSDS information
and original samples are to be provided by the manufacturer.
B. The media cells, cell stages, and residence times shall meet or
 exceed the minimum requirements.

C. Media bed face velocities shall not exceed the specified rate for
this application.

D. Media pressure losses shall not exceed the design limitations.

2.06 FINAL FILTER

A. The particulate final filter section shall include a 95% high

efficiency after filter based on ASHRAE Standard 52.1, and shall
carry Class 2 certification in accordance with UL Standard 900.

B. Filter face velocities and filter resistances shall not exceed

the allowances for the project.

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C. Extruded aluminum particulate filter tracks with positive air

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seals shall be used to allow easy changing of the filters, and
to ensure air does not bypass the filters.

D. Access doors to the filters shall use quick release, snap acting

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type, positive pressure latches.
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E. The final filter section shall monitor the pressure drop by a
magnehelic differential pressure gauge or a photohelic pressure
switch/gauge.

2.07 BLOWER SECTION

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A. Standard plenum fan blower arrangement shall be used for a draw

thru or blow thru application. The blower shall be an industrial
centrifugal type of suitable corrosion resistance construction.
Bearings shall be used on L10 minimum life of 40,000 hours of
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average life of 20,000 hours. Adjustable motor base shall have a

two point leveling and tension adjustment.
B. The blower assembly shall be installed utilizing isolation mounts
for vibration purposes.
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C. Sheaves shall be sized for a minimum of 150% of motor horsepower,

fully machined, cast iron, keyed and securely attached to the
shaft. The blower shall be driven using a heavy industrial
adjustable V belt assembly which is oil and heat resistant and
non-static conducting per RNA standards.

D. The blower section shall have accessibility for maintenance

purposes, including balancing, grease nipples, tachometer (RPM)
opening.

E. Optional spark proof blower construction shall be provided for

such rated environments.
 F. The motor shall be totally enclosed fan cooled (T.E.F.C.) type
rated for the intended duty cycle.

G. Optional disconnect, starter, and controls shall be provided as

required to suit the application.

2.08 PACKAGING AND HANDLING

A. The package fresh air filter unit shall be capable of preventing

any deflection during rigging, handling, transportation,
operation, or servicing.

B. Lifting lugs and/or anchor bolt locations shall be provided for

safe handling and operation of the system.

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PART 3 – EXECUTION

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3.01 INSTALLATION

A. The package fresh air filter unit shall be installed in the

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locations as shown on the contract drawings, in accordance with
the manufacturer’s recommendations.
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3.02 TESTING AND COMMISSIONING

A. The package fresh air filter unit shall be tested with the
completed air conditioning system in accordance with the
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recommendations of the agencies listed in Part 1 Para 1.02.

B. Tests to demonstrate the performances shall be made by competent

and experienced engineers in the presence of the Ministry
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Representative unless otherwise directed. Any adjustments

necessary to conform to the specification and/or the duties
required shall be made at no cost to the Ministry.
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