Note to spec. writer: Tailor these specifications to meet your specific project requirements. Items that are underlined require input regarding the separator model chosen, quantity, or configuration. When a paragraph is bulleted, choose the paragraph that pertains to the separator you wish to specify. Our 350 and 550 gallon separators have some dimensions that vary from the 1000 through 30000 gallon separators. When values are in italic and bold type, the first value pertains to 1000 through 30000 gallon separators and the second value pertains to 350 and 550 gallon separators. Contact McTighe for assistance in preparing specifications on separator configurations not included in this section.

Provide One (1) McTighe Industries, 3405 S. Westport Ave., Sioux Falls, SD 57106 (888)-776-0581, Model (OWS or POWS) corrugated parallel plate oil-water separator having a flow rate of gallons per minute and producing a free oil effluent quality of ppm.

Design Criteria

The oil-water separator shall be a special purpose factory assembled unit which is the standard product of a manufacturer regularly engaged in the production of such equipment with similar units operating for a minimum of five (5) years.

The separator shall be designed in accordance with Chapters 3 and 5 of the American Petroleum Institute (API) Manual on Disposal of Refinery Wastes (Volume on Liquid Wastes) and API Bulletin Number 1630 "Wastewater Handling and Treatment for Petroleum Marketing Facilities"-- First Edition May 1979. Both of these standards are out of print and are replaced by API 421 "Monographs on Refinery Environmental Control -- Management of Water Discharges" -- First Edition February 1990.

Separator shall be designed for intermittent, variable or continuous flows of water, oil and/or any combination of non-emulsified oil-water mixtures. The influent is composed of (list type of hydrocarbons, specific gravities, ambient conditions and water characteristics)

* (Model OWS) -- Separator shall process uncontrolled surges of water, oil, or oil-water mixtures ranging from zero flow up to 100% of maximum hydraulic throughput capacity and produce a free oil effluent quality of 15 ppm or less.

* (Model POWS) -- Separator shall process uncontrolled surges of water, oil, or oil-water mixtures ranging from zero flow up to 100% of maximum hydraulic throughput capacity and produce a free oil effluent quality of 10 ppm or less.

Separator shall be designed in a manner to minimize solids accumulation in the corrugated plate pack to prevent plugging problems. This must include providing corrugated plates inclined upwards at a minimum angle of 30o and allowing an open area beneath the plate pack so that solids can not build-up in front of the plate pack.

Separator shall be constructed for transport to job site as one integral unit, ready for immediate installation. Field splicing or field fabrication is unacceptable.

Construction

The separator shall be cylindrical and construction and thickness shall be in strict accordance with UL-58. In addition, separator steel thickness shall be verified by calculations to include a 2.5 or better safety factor taking into account the design burial depth and using a soil density of 135 lb/ft3.

For direct burial installations, the separator shall include a 30 year limited warranty against external corrosion failure. Separator must be commercially sandblasted to a minimum requirement of SSPC-SP6 and coatings must be applied in the factory. Provide coating kits to touch-up scratches that might occur during shipment or installation.

* (Optional) -- Provide a factory applied interior epoxy coating that is compatible with the hydrocarbon and water characteristics specified above. Separator must include interior seal weld and be sandblasted prior to the application of coatings.

If Double Wall

* (UL-1746 Jacketed design) -- Separator shall be built in accordance with Underwriters Laboratories, Inc. UL-1746 Part III and provide 360o (Type II) secondary containment. Construction shall consist of a steel inner shell built to UL-58 construction criteria, wrapped with a UL listed stand-off and a fiberglass reinforced polyester resin (FRP) outer shell. Secondary containment of the separator manways must be provided to the first manway flange. The exterior fiberglass jacket shall show no holidays (pinholes) when tested with a Tinker & Rasor Model AP-W holiday detector set at 35,000 volts. Separator shall be warranted against external corrosion for 30 years without the need for cathodic protection.

* (UL-58 Type I or Type II design) -- Separator must be double wall and provide 360o secondary containment. Construction shall consist of steel inner shell and steel outer shell built in accordance with (UL-58 Type I or UL-58 Type II) construction criteria.

The inlet pipe shall be a inch 150 lb. flat faced flange connection. An inlet flow diffusing nozzle shall be installed at the inlet end of the separator, located at the furthest diagonal point distant from the outlet, (12", 8") from the top of the separator.

Inlet to flow against a, 10 gauge minimum thick, single corrugated plate set at a 33o angle and bolted to steel supports. Incoming flow must be directed on the single corrugated plate at a minimum angle of 85o to reduce the flow velocity and spread the flow out over the cross sectional area of the separator.

A second series of corrugated parallel plates shall be downstream of the first and set at a (45°, 30°) angle. The corrugated parallel plates shall be constructed of 10 gauge minimum thick carbon steel and shall be removable from steel corrugated plate pack housing. Plate pack shall be as close to the inlet pipe as possible to effect coalescence of the oil particles as soon as possible.

A sludge baffle shall be installed (12", 8") in height and located directly below the separator access manway for ease of maintenance.

The discharge pipe shall be installed at the outlet end of the separator, located at the furthest diagonal point distant from the inlet, (6", 4") from the bottom of the separator and tack welded or supported to the end plate of the separator. The outlet shall be a inch 150 lb. flat faced flanged connection.

* (Model OWS) -- The separator shall be equipped with one (1) (30", 24") I.D. manhole UL approved complete with extension to within 1' 0" of grade, gasket, cover and bolts. (Note: in non-traffic area, manway can be extended above grade.)

* (Model POWS) -- Separator shall be furnished with an oleophilic oil coalescer designed to intercept oil droplets down to 20 microns in size. The polypropylene media shall be 6" thick and come housed within a 304 stainless steel frame with lifting hook and retrieval arm.

Separators equipped with an oleophilic coalescer must include access to completely remove and reinstall the coalescer from grade without entering the separator vessel. If coalescer is in multiple pieces, separate channels must be provided for each piece and the width and length of the access manway must be greater than or equal to the total cumulative width and length of the oleophilic coalescer to facilitate easy removal and reinstallation during maintenance operations.

Separator shall be furnished with fittings for vent, waste oil removal and gauge. Separator shall include lifting lugs located at the balance points.

Submit prototype test report information that demonstrates the ability of proposed separator to meet performance requirements called for in this specification. Samples must have been performed by an independent test laboratory and separator design and symmetry must be similar to unit proposed. Testing time period shall have lasted a minimum of three (3) tank volume changes with continuous water flow and continuous oil injection in the influent. Starting and stopping of the influent flow is unacceptable. Influent oil concentrations must be a minimum of 3000 ppm.

Accessories - Note: this listing includes some of our standard accessories, contact McTighe for details and specifications on equipment not listed below.

* (High Oil Alarm) -- A solid state oil alarm indicating system shall be provided by the separator manufacturer and shall consist of one (1) (NEMA 4 or NEMA 4/7) control panel A and one (1) stainless steel oil interface level sensor. Control panel shall include alarm light, alarm horn and silencer. Level sensor must be UL approved intrinsically safe.

* (Automatic Oil Pump-out) -- An automatic oil pump-out system shall be provided by the separator manufacturer and shall consist of one (1) (NEMA 4 or NEMA 4/7) control panel B, one (1) stainless steel level sensor, and one (1) self-priming, centrifugal pump with a hp, phase, 60 Hz, explosion proof motor to provide gpm at ft of head. System must be designed to prevent the transfer of water to storage.

* (Inlet Shut-off Valve) -- Separator must include an automatic inlet shut-off valve consisting of a butterfly valve with extension stem and torque tube and a NEMA 4/7 electric actuator with manual override. Valve must not be placed in the separator discharge piping which can cause flood-out and/or pressurization of the separator. Manual oil stop valves will not be acceptable.

* (Automatic Water Pump-out) -- Separator must include an automatic water pump-out system and shall consist of one (1) (NEMA 4 or NEMA 4/7) control panel B, one (1) water level sensor, and one (1) (or two (2) pumps for duplex system) submersible pump with a hp, phase, 60 Hz, explosion proof motor to provide gpm at ft of head. Pump must be installed in an integral water compartment on the end of the oil-water separator. Compartment must include a UL approved manway with extension, gasket, cover, bolts and be properly sized to remove and reinstall submersible water pump. Provide guide rails or cables mounted in access manway for removal and reinstallation of pump from grade. Check valve must be placed in pump discharge piping.

* (Sludge compartment paragraph to be inserted under Construction specification section) Separator shall include an integral solids interceptor on the inlet end of the oil-water separator for collecting and storing sludge and debris. Compartment must include a UL approved manway with extension, gasket, cover, bolts for access and solids removal. Solids interceptor design must not allow oil to accumulate in the interceptor.