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 corrugated plate oil water separation 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:

B16.1 Cast Iron Pipe Flanges and Flanged Fittings, Class 25, 125, 250 and 800

American Society for Testing and Materials (ASTM) Publications:

A-36 Structural Steel
A-53 Pipe, Steel, Black and Hot Dipped, Zinc Coated, Welded Seamless
A283 Low and Intermediate Steel Plate of Structural Quality

American Welding Society (AWS) Publications:

D1.1-84 Structural Welding Code, Steel
A5.1 Mild Steel Arc-Welding Electrodes

Standard Welding Terms and Definitions

Standard Welding Symbols

Steel Structures Painting Council (SSPC) Publication:

SSPC-SP-10 Near White

American Institute of Steel Construction (AISC) Steel Construction Manual, 8th Edition

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 oil water separator and accessory equipment including principle dimensions and location of fittings. Data shall include weight and distribution of weight with the unit empty and filled with water.

1.3.2.2 Test results, signed by the manufacturer, which indicate the oil water separator is capable of handling specified effluent concentration, pH, fluid temperature and concentration of oil and grease. Tests on this model shall have been done within the last 3 years.

1.3.2.3 Provide calculations of oil water separator loading rate at the design flow rate.

1.3.3 Submit the following after fabrication:

1.3.3.1 Verification:

1. Written verification on the fabricator’s letterhead that surface preparation and coating application were performed in accordance with the specification and coating specification and system manufacturer’s printed recommendations;
2. That the unit was hydraulically leak tested for a period of at least 4 hours before further surface preparation and coating;
3. That the surface preparation and coating process was performed at a facility owned and operated by the manufacturer;

1.4 MANUFACTURER’S SERVICE REPRESENTATIVE'S REPORT AND CERTIFICATE: Submit service representative's complete signed report of results of the inspection, operation, adjustment, and tests. Report shall include detailed descriptions of points inspected, tests and adjustments made, quantitative results obtained if such are specified, and suggestions for precautions to be taken to ensure proper maintenance. Include the manufacturer’s certificate that equipment conforms to specified requirements and is ready for permanent operation and that nothing in installation will render manufacturer's warranty null and void.

1.5 DELIVERY, STORAGE, AND HANDLING MATERIALS:

1.5.1 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.

1.5.2 Handling: Handle the oil water separator in such a manner as to ensure delivery to final location in sound, undamaged condition. Take special care not to damage interior and exterior surfaces of the inclined plate clarifier. Make satisfactory repairs to damaged material(s) at no cost. Carry and do not drag materials. Handle the oil water separator according to manufacturers information.

1.6 QUALITY ASSURANCE:

1.6.1 Inspection: Examine each component of the oil water separator 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 the oil water separator’s operation, shall constitute cause for rejection.

1.7 WELDER QUALIFICATIONS:

1.7.1 Welders shall be previously qualified by passing the tests prescribed in the AWS Standard Qualification Procedure, or by passing such other tests as the Engineer may accept.

1.7.2 Welders shall have been tested within the past twenty four months and their qualifications shall be considered as remaining in effect unless the welder is not engaged in a given process of welding for a period exceeding six months.

PART 2 - OIL/WATER SEPARATOR DESIGN CRITERIA AND MANUFACTURING SPECIFICATIONS

2.1 Oil/Water Separator Applications & Performance

2.1.1 Applications: The oil water separator shall be used to separate entrained oil droplets from a wastewater stream having a flow rate of   *   gallons per minute. The unit is baffled to dissipate hydraulic flow through the system. A sand trap is incorporated in the inlet baffle compartment to collect and allow for removal of heavy settleable solids.

The oil droplets coalesce from entrainment as the laminar flow moves through the corrugated plates. The oil collects on the ceiling of the flow channel, coalesces into larger droplets and flows upward due to the differential in specific gravity of the oil and water mixture.

2.1.2 Performance: The oil water separator shall remove 100% of oil droplets 60 micron or larger at the designed flow rate. Calculations showing flow rate, plate pack area oil droplet buoyancy shall be provided to demonstrate that the specified oil water separator will remove 100% of oil droplets larger than 60 microns.

2.2 OIL WATER SEPARATOR Manufacturing specification

2.2.1 The manufacturer of the oil water separator and related components shall have been manufacturing oil water separators of the following specified design for at least five years. The oil water separator and components shall be fabricated and assembled at the steel fabrication facility owned and operated by the manufacturer. Sandblasting and coating operations shall also be performed at the manufacturers’ facility. The manufacturer shall maintain a quality control staff to perform quality assurance checks during fabrication and assembly.

2.2.2 Corrugated plates shall be set at a minimum of 45 degrees above the horizontal plane and the space between plates shall be at least 0.75 inches.

2.2.3 The maximum flow rate through the inclined plate pack shall not exceed 0.40 gallons per minute per square foot of horizontal projected area. (Horizontal projected area of an inclined plate set at 45° is 70% of the total surface area).

2.2.4 To ensure full utilization of all plate areas. Velocities through the unit shall be kept below 1 FPS. Flow velocity calculation shall be submitted for feed ducts, feed bay and plate separators.

2.2.5 The oil water separator shall be provided with minimum 4 inch freeboard at design flow rate.

2.2.6 The minimum plate spacing shall be 0.75 inches. Plates shall be fabricated of fiber reinforced plastic. The plates shall be supported by dividers constructed of stainless steel, Teflon or molded plastic inserts.

2.2.7 The plates shall be a minimum of 0.06 inches thick FRP. The plates shall have a resin rich surface to prevent fiber show. The plates shall be produced by contact molding or machine extrusion, "hand or spray lay-up fabrication" will not be acceptable.

2.2.8 The plates shall be 42" wide supported on the sides and center, such that unsupported distances shall not exceed 12". Settling plates wider than 48" shall be supported on 12" center or provide documentation and test results that the plates will withstand a load of 100% filled with sludge, specific gravity 1.4 or above, with all water drained from the separator, without plate collapsing. Manufacturer shall provide a minimum of five installation references with at least five years service without failure.

2.2.9 Gasket materials utilized in the plate construction shall be Viton or Teflon. All assembly clips shall be constructed of Teflon.

2.2.10 Inlet and outlet shall be flanged connections drilled to ANSI B16.1.

2.2.11 The oil overflow weir and the final effluent weir shall have adjustable weir plates.

2.2.12 All outlets shall be flanged fittings and there shall be outlets for the sand trap, sludge collection area, oil collection weir and final effluent.

2.2.13 The unit shall be equipped with a cover constructed in easily removal sections and at least one section shall have a 4" flange to vent accumulated gases.

2.3 STRUCTURAL:

2.3.1 All structural and tank steel stresses shall be within the allowable limits shown in the Steel Construction Manual of the American Institute of Steel Construction, Eighth Edition.

2.3.2 The unit to be structurally designed for installation in Seismic Zone   *  in accordance with 1998 Uniform Building Code.

2.3.3 Oil Water Separator shall be fabricated from ASTM A-36 steel.

2.3.4 All exterior welds shall be continuous seal weld or the weld must be caulked before surface coating.

2.4 TESTING:

2.4.1 All seal welds shall be visually checked for continuity, pinholes, and voids.

2.4.2 The entire unit shall be shop-hydrostatically tested. Documentation of hydrostatic test shall be provided.

2.5 SURFACE PREPARATION AND COATING

2.5.1 Surface Preparation: The steel surfaces must be dry and clean in accordance with the following requirements. Remove all grease, oils and contaminants as outlined in SSPC SP1. Remove all weld splatter and grind burrs on cut edges and rough welds smooth. Blast clean all surfaces after fabrication in accordance with SSPC SP10 with profile depth of 1.5-2.0 mils. Apply first primer before any rust bloom forms.

2.5.2 Caulking: All exterior non-seal welding joints shall be filled with rubber caulking before painting.

2.5.3 Exterior Surfaces:

Shop First Coat: Apply one coat average dry film thickness of two mils minimum, of a high-build catalyzed epoxy. Apply to all steel surfaces except the areas within 2 inches adjacent to field welds and surfaces specified to be hot-dip galvanized. The paint shall be Hempel 4563U.

Shop Finish Coat: Apply one coat average dry film thickness of 1.0 mils minimum, of a polyurethane paint. Recoat at time interval recommended by the manufacturer, the final coat shall be Hempel 5595U.

Third Coat: Field touch-up of damaged and unpainted areas shall be the same as specified first and second coats at the same film thickness.

The total dry film thickness shall be an average of 4 mils.

2.5.4 Interior Surfaces:

Shop First Coat: Apply one coat average, dry film thickness of four mils, of an immersion grade high-build catalyzed epoxy. Apply to all steel surfaces except the areas within 2 inches adjacent to field welds and surfaces specified to be hot-dip galvanized. The paint shall be Hempel 15409.

Shop Finish Coat: Apply one coat average, dry film thickness of 4 mils, of an immersion grade high-build catalyzed epoxy. Recoat at time interval recommended by the manufacturer, the final coat shall be Hempel 15409.

Third Coat: Field touch-up of damaged and unpainted areas shall be the same as specified first and second coats at the same film thickness. (Liquid Contact).

The dry film thickness shall be an average of 6 mils.

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 the oil water separator in such a manner as to ensure delivery to final location in sound, undamaged condition. Take special care not to damage interior and exterior surfaces of oil water separator and associated supports and pipe coatings or linings. Make satisfactory repairs to damaged material(s) at no cost. Carry and do not drag materials. Handle oil water separator according to manufacturers information.

PART 4 - EXECUTION

4.1 Installation: Oil water separator 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 the oil water separator fully operational. Do not weld tank surfaces, interior or exterior, it will permanently damage the interior lining. If welding has inadvertently occurred, the interior surface affected shall be abrasively ground to white metal and two coats of Hempel 15409 applied, with air dry between coatings.

4.2 Field Inspection Services: Examine each component of the oil water separator 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 the oil water separator operation, shall constitute cause for rejection.

4.3 Start-Up Testing: Manufacturer’s field representative shall inspect and test unit and certify that the installation has been performed in accordance with manufacturer’s recommendations and that the system is ready for operation by others. Inspection shall consider, but not be limited to, the following:

1. Soundness (without cracked or otherwise damaged parts).
2. Completeness in all details, as specified.
3. Correctness of settling alignment, set points and relative arrangement of each component.
4. Confirm that the unit is level within ¼" side to side and end to end.
5. Inspect unit for leakage.
6. Inspect coating integrity to insure installation contractor has applied touch-up paint to all scratches, blemishes and/or coating discontinuity that occurred during shipping and installation.

PART 5 - SUGGESTED MANUFACTURER:

The oil water separator shall be model number #  *   manufactured by:

Hoffland Environmental, Inc.
10391 Silver Springs Road
Conroe, Texas 77303

(936) 856-4515 phone / (936) 856-4589 fax
e-mail: hoffland@flex.net

*Model Number  *  
*Check following page for alternates.

HOFFLAND ENVIRONMENTAL, INC.
OIL / WATER SEPARATOR

MODEL NUMBER Pack Size Nominal Flow Rate Section Variable 2.3.2 OWS-050 OWS-100 OWS-200 OWS-400 OWS-800 OWS-1200 OWS-1600 OWS-2000 OWS-2400 1/4 1/2 1 2 4 6 8 10 12 50 100 200 400 800 1200 1600 2000 2400 S E I S M I C Z O N E 1 O R A S A R E A R E Q U I R E S