Section 11161 SILO DISCHARGER (SLIDING FRAME)

Section 11161

SILO DISCHARGER (SLIDING FRAME)

PART 1 - GENERAL

1.1 SUMMARY

A. Section Includes:

1. Sliding frame discharge assemblies. B. Scope:

1. The silo discharge assemblies, each consisting of a lower hopper section, sliding frame collector, screw conveyors, and gate, will be installed on the existing cake silos following demolition of the existing systems.

2. The system Work must be performed in the proper sequence and phasing as detailed in Section 01140, Work Restrictions. This includes installation of discharger assemblies in phases.

C. Related sections include but are not necessarily limited to:

1. Division 01, Additional General Requirements

2. Section 01140, Work Restrictions

3. Section 05505, Metal Fabrications

4. Section 09800, Protective Coating

5. Section 11005, Equipment: Basic Requirements

6. Section 11121, Screw Conveyors

7. Section 16220, Electric Motors

8. Section 16418, Variable Frequency Drives Below 100 HP

9. Section 16442, Control Panels

10. Section 17300, Control Strategies

11. Section 17405, Process Instrumentation and Control

D. Coordination:

1. Discharge to Cake Silo Pumps.

2. Coordinate delivery, installation, and startup of sliding frame and cake silo pumps.

1.2 QUALITY ASSURANCE

A. Referenced Standards:

1. American Iron and Steel Institute (AISI):

a. Steel Products Manual

2. ASTM International (ASTM):

a. A36 Standard Specification for Carbon Structural Steel

3. American Welding Society (AWS):

a. A5.1 Standard Specification for Carbon Steel Electrodes for Shielded Metal

Arc Welding

b. D1.1 Structural Welding Code Steel

B. Qualifications:

1. Supplied by a single manufacturer or supplier.

2. Manufacturer shall have a minimum of three similar size and configuration units in operation.

1.3 WARRANTY

A. The silo discharger and all components specified in this section shall be warranted by the manufacturer for a minimum three (3) year period after Beneficial Occupancy of the Work pursuant to “use prior to final completion” of the general conditions, against defects in workmanship and materials.

1.4 SUBMITTALS

A. Shop Drawings:

1. See requirements in Section 11005, Equipment: Basic Requirements.

2. Manufacturer's literature, illustrations, specifications, detailed drawings, data and descriptive literature on all valves and appurtenances.

3. Complete motor data, as required by Section 16220, Electric Motors.

4. A letter from the discharger manufacturer confirming compatibility between the drive motor and VFD being provided.

5. Control panel layout and construction Drawings, as required by Section 16442, Control Panels and as required in section 17405.

6. Panel elementary control diagrams and interconnect wiring diagrams including power wiring.

7. Functional description of internal and external instrumentation and control.

8. Deviations from Drawings and Specifications.

9. Engineering data including dimensions, materials, size and weight.

10. Structural design calculations sealed by Professional Civil or Structure Engineer registered in the State of California.

11. Fabrication, assembly and installation details, and wiring diagrams.

B. Operation and Maintenance Manuals in accordance to Section 01783, Vendor

Equipment Manuals.

1.5 PROJECT CONDITIONS A. Location:

1. Dewatered municipal biosolids storage facility.

2. Interior location.

PART 2 - PRODUCTS

2.1 ACCEPTABLE MANUFACTURERS

A. Subject to compliance with the Contract Documents, the following manufacturers are acceptable:

1. Putzmeister.

2. Schwing Bioset.

3. Biosec Enviro.

4. Or Equal.

2.2 MATERIALS

A. Steel Plate: Stainless steel, ASTM A276, Type 304

B. Steel Shapes: Stainless steel, ASTM A276, Type 304

C. Silo Extension: Stainless steel, ASTM A276, Type 304

D. Sliding Frame: Steel, ASTM A36

E. Structural Members: Stainless steel, ASTM A276, Type 304

F. Screw Flights: Stainless steel, ASTM A276, Type 304

G. Screw Torque Tubes: Stainless steel, ASTM A276, Type 304

H. Hardware: Stainless steel, ASTM A320, Type 316

I. Gates, Slide Gate Blade: Stainless steel, ASTM A276, Type 304

J. Slide Gate Frame: Stainless steel, ASTM A276, Type 304

2.3 EQUIPMENT

A. Performance and Configuration Requirements:

1. Material Description:

a. Maximum Sludge Density, 65 lb/cu. ft. (1040 kg/m3). b. Minimum Sludge Density, 60 lb/cu. ft. (960 kg/m3).

c. Maximum Sludge Moisture, 75 percent. d. Minimum Sludge Moisture, 65 percent. e. Abrasive.

f. Corrosive.

g. Contains oil, grease, ferric chloride, and polymer. h. Maximum Lump Size 1 inch.

B. Sliding Frame Storage Silo (15MGAT803; 15MGAT823; 15MGAT843; 15MGAT863):

1. Quantity: Four (4)

2. Approximate Size:

a. Diameter: 12 feet (plus or minus)

b. Height: As shown in Drawings.

c. Existing bin increases height an additional 30 feet.

C. Bin Extraction screw conveyors (15MCVY804; 15MCVY824; 15MCVY844;

15MCVY864;)

1. Quantity: Four (4)

2. Size: 24-inch diameter.

3. Type: Shafted with ribbon flights.

D. Gates (15MGAT805; 15MGAT825; 15MGAT845; 15MGAT865):

1. Size 24 inches x 24 inches

E. Capacity

1. Discharge Rate per Silo: 175 gpm

2.4 COMPONENTS A. General:

1. Design for both continuous and for intermittent operation at a capacity not less than that specified while material level is maintained.

2. Static and dynamic loading of the mechanical and structural components shall be calculated using the maximum density of the dewatered sludge. Structural calculations shall assume bins are 100 percent full of maximum density sludge. All bin structural design calculations shall be sealed by a registered Professional Civil or Structure Engineer in the state of California.

3. The compatibility of the equipment with the feed equipment and all other related equipment shall be the responsibility of the CONTRACTOR.

4. The entire system (bins, dischargers, conveyors, gates, etc.) will be supported from the existing silo to which it is attached. No supports or bracing will be permitted from the floor or from the adjacent platform.

B. Storage Bin:

1. The bins will be constructed of plate of minimum 1/4 inch thickness or as required by the structural analysis, whichever is greater, and will be reinforced as required.

2. Maximum deflection to the hopper shall be limited to less than 1/200 of the span. Reinforcing members such as angles, beams, stiffeners, and gussets shall be externally mounted to provide a smooth interior surface.

3. Each bin shall be provided with hinged, gasketed and bolted access hatch located at the bin floor level. Size nominal 30-inch diameter.

C. Sliding Frame Discharger:

1. General:

a. Fabricate with integral structural support members to ensure integrity throughout the entire silo operating range.

b. The frame shall be hydraulically driven and shall move across the flat bottom. On the front stroke, the beveled edge of the frame shall undercut the biomass. On the return stroke, the face of the frame will plow the material into the discharge screw.

c. The leading edge of the sliding frame shall include a beveled edge of less than 45 degrees from horizontal to sweep under the biomass in the hopper.

d. The inside edge shall have a bevel greater than 45 degrees from horizontal to draw biomass to the extraction screws and to impart a downward force on the trailing edge of the sliding frame to maintain contact with the silo floor.

e. The sliding frame will assure that the discharge conveyor is constantly filled with sludge cake.

f. The cycle time of the sliding frame shall be adjustable between 1 minute to 2 minutes per cycle. The cycle time of the sliding frame shall be defined as one forward and one reverse stroke of the sliding frame.

g. Two sliding frame guides shall prohibit any vertical movement of the frame;

guides shall be bolted to the floor bottom or side wall.

2. Seal Packing Box:

a. Designed for maximum sludge pressures anticipated from a full silo height.

b. Compressible packing gland type design, with a minimum of three rows of teflon impregnated packing ropes or shall be sealed with multiple chevron ring seals with a grease purged lantern ring via a central grease lubricator located adjacent to the packing box or on the hydraulic power unit.

3. Hydraulic Cylinder:

a. Rigidly supported by a structural member integral to the silo support system. This support shall be designed to withstand the weight of the hydraulic cylinder and connecting rod.

b. The hydraulic cylinder supports shall be designed to withstand the force transmitted at the maximum hydraulic pressure.

c. Minimum diameter of 5.5 inches and a stroke length of 27 inches.

d. The hydraulic cylinder rod shall be hard chrome plated to a minimum thickness of 0.025 millimeter. The hydraulic cylinder assembly shall include a nitrided steel extension rod that passes through the silo wall.

D. Extraction Screw Conveyor:

1. General:

a. One (1) or more extraction screw conveyor(s) will in general consist of conveyor with continuous flighting, shafts and couplings, high strength shaft bolting, trough ends, seals, bearings, electric motors, speed reducers, supports and grease fittings.

b. Provide means to remove and replace the extraction conveyor within the location and structure it is housed.

2. Screws:

a. The extraction screw conveyor(s) shall be furnished complete with supports suitable for mounting in the bottom of the bin.

b. The extraction screw conveyor assembly shall be an integral unit with the bin with a single center discharge for each screw.

3. Drive:

a. The extraction screw conveyor assembly will incorporate a drive assembly to power the screws separately.

b. The drive assemblies will consist of a 15 HP (minimum), 480 Volt, 3 phase, TEFC motor with an AGMA Class I helical gear screw conveyor drive with adapter flange mounting and end thrust capacity to achieve specified speed.

c. The motor shall be inverter duty rated for 6 to 90 Hz with sufficient power to start and continuously operate when under full bin load.

d. Motors shall be in accordance with 16220, Electric Motors.

4. Flighting:

a. Multiple pitch flight to promote even draw-down. b. Minimum of 1/4 inch thick.

c. Torque tube shall be of sufficient size to limit deflection to 0.2 inch maximum. Pipe ends shall have a sleeve coupling with shear bolt to stub shaft to mount the drive.

5. Shafting: End shafts will be fabricated from C 1045 steel, minimum.

6. Trough End Bearings: Each screw will include regreasable roller bearing at non- drive end. The bearing will be capable of handling all impending radial loading.

7. Stuffing Box:

a. Shaft seals will be provided at the trough ends and shall be of the packing gland type with a minimum 4 rows packing.

b. A lantern ring with grease purge connection shall be provided for additional sealing.

8. Troughs:

a. Troughs shall be integral to the silo and shall transport sludge to outlets.

b. Minimum thickness of 1/4 inch complete with external stiffeners as required.

9. Slide Gates:

a. Slide gates (one for each conveyor) under the bin shall be provided to seal the bin when not in use.

b. Gate opening shall be 24 inches x 24 inches. c. Pneumatically operated.

d. Designed to operate as an integral part of the system and shall be supplied by the manufacturer.

e. In closed position, the gate blade shall seal against an elastomer seal. Seal leakage shall not exceed 0.05 GPM per linear foot of perimeter.

10. Guarding: OSHA style guarding will be provided by the manufacturer at all rotating components.

E. Hydraulic Power Unit:

1. General:

a. Provide a hydraulic power unit for driving the sliding frame discharger. b. Provide one separate unit for each discharger system

c. Completely self-contained and factory assembled.

d. The frame shall be made of welded steel construction adequate to support all components and designed to be anchored to a suitable base.

2. Electric Motor:

a. 15 HP (minimum), TEFC, 1,800 rpm, with a service factor of 1.15, suitable for 480V/3 phase/60 Hz supply voltage.

b. Electric motors shall be provided in accordance with Section 16220, Electric

Motors.

3. Hydraulic System:

a. An axial piston type hydraulic pump, providing variable displacement volume shall operate the sliding frame.

b. Axis positioning shall be via a proportional solenoid to vary the pump swash plate angle.

c. Peak discharge pressure shall be limited by a factory tested pressure compensator, relief valve and pressure switch.

d. The power unit shall include hydraulic oil (coordinate brand of oil with Owner), clean-out cover, reservoir breather/filler cap, oil temperature and level indicator, return line filter (10 micron absolute) with flow bypass, filter contamination sensor, high oil pressure mechanical relief valve, high oil temperature switch, high oil pressure switch, low oil level switch, and 3/4-inch reservoir drain with shut-off valve.

e. Oil reservoir shall be installed such that it can be easily drained by gravity into an 8-inch high container.

f. Hydraulic oil reservoir shall be designed and sized with a minimum of 2-1/2- minute detention time at maximum hydraulic oil flow.

g. The reservoir shall be baffled into two sections.

h. Manufacturer of sliding frame silo shall provide high pressure hydraulic tubing and fittings, hoses, and ancillary equipment between the power unit and sliding frame hydraulic cylinder,

i. Hydraulic tubing shall be rated for a minimum working pressure of 4,000 pounds per inch.

4. Motion of the sliding frame shall be governed by solenoid operated valves located on the power unit.

2.5 LOCAL CONTROL PANEL

A. Provide a control panel for Sliding Frame Storage Silo. The panel shall include all interface, alarm and indicating devices as shown on the P&IDs and electrical Drawings for local and remote operation of the sliding frame gate. 4 LCP shall include controls to operate the hydraulic power unit, and independently operate each sliding frame gate. Panel requirements are found in separate section.

B. Equipment control panel shall be factory pre-assembled, pre-wired, and shall contain all necessary control devices for the operation of the frame, extraction screw conveyor, slide gate, and other devices specified herein. Control devices shall include motor starters, overloads, control power transformer, control switches, pilot lights, relays, programmable controller, and other devices as required for a complete and operating system. Entire control panel assembly shall be UL listed and mounted to the hydraulic power unit

C. Control panel shall be provided per the requirements of Section 16442, Control Panel, and applicable sections of Section 17405, Process Instrumentation and Control. Enclosure shall be NEMA 4X, 316 stainless steel construction with 14 gauge minimum thickness.

D. The control panel shall be suitable for connection to a single 480 volt AC, 3 phase, 60

Hz power supply.

E. The control panel shall include a main circuit breaker disconnect with externally operable handle lockable in the OFF position.

F. The control panel shall include a motor starter with overload protection for the hydraulic power unit.

G. A separate VFD (Variable Frequency Drive) shall operate the extraction screw conveyor.

H. Programmable Logic Controllers:

1. Digital solid state logic systems

2. Central processor unit, memory, input/output cards, racks, power supply, and all interconnecting cables.

3. Configure to implement the sludge pumping unit control and monitoring functions specified herein.

4. Modular design permitting the expansion of the programmable logic controller system through the addition of input/output modules and system programming.

5. Include provisions for the future addition of one analog and one discrete input and/or output signal module without any modification to the programmable logic controller processor, memory, rack, or power supply systems.

6. The PLC shall be Modicon as specified in Section 17405, Process

Instrumentation and Control.

2.6 SPARE PARTS

A. Extra Materials.

1. Furnish the Owner the following extra parts:

a. One set of rope packings for each Conveyor and Sliding Frame seal. b. One set of hydraulic filters for each power unit.

2. Initial supply of necessary lubricants, as recommended by the manufacturer.

PART 3 - EXECUTION

3.1 PREPARATION

A. Field verify dimensions of existing silos prior to fabrication.

B. For protective coating of all components and required surface preparation refer to section 09800, Protective Coating.

3.2 INSTALLATION

A. See Section 11005, Equipment: Basic Requirements.

B. Vertically and horizontally align, level and plumb units into position.

3.3 MAINTENANCE OF INSTALLED EQUIPMENT, GATES AND VALVES

A. Maintain the operability and functionality of all installed equipment, gates and valves between the time of installation and the commissioning period. See Specification section

01660 for requirements.

3.4 MANUFACTURER’S FIELD SERVICES

A. Furnish the services of authorized technical representatives of the Manufacturer to assist/inspect the installed equipment and to certify that the equipment has been properly installed and is ready to operate, train OCSD personnel, conduct pre-operational mechanical checkout of the equipment, place equipment into operation, optimize the performances of the equipment and perform the field performance testing.

B. At a minimum, conduct three separate site visits as follows:

1. Inspection of equipment installation (8 hours minimum)

2. Training of OCSD Personnel: See Specification section 01820, Training of OCSD Personnel, for requirements.

3. Commissioning: See Specification section 01810, Commissioning, for requirements. Number of hours shall be as required to meet all testing and commissioning requirements, but shall not be less than 16 hours.