Gas_Burner_Spec.pdf

City of Santa Fe Anaerobic Digester December 2017 – Rev Issued for Construction

DIGESTER GAS EQUIPMENT

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Attachment A

SECTION 46 73 35

DIGESTER GAS EQUIPMENT

3 PART 1 - GENERAL

4 1.1 SUMMARY

A. Section Includes:

1. Digester gas equipment.

14 1.2 QUALITY ASSURANCE

15 A. Referenced Standards:

16 1. American Society of Mechanical Engineers (ASME):

17 a. B16.1, Gray Iron Pipe Flanges and Flanged Fittings: Classes 25, 125, and 250.

18 2. ASTM International (ASTM):

19 a. A182, Standard Specification for Forged or Rolled Alloy and Stainless Steel Pipe 20 Flanges, Forged Fittings, and Valves and Parts for High-Temperature Service.

21 b. A351, Standard Specification for Castings, Austenitic, for Pressure-Containing Parts.

22 3. National Electrical Manufacturers Association (NEMA):

23 a. 250, Enclosures for Electrical Equipment (1000 Volts Maximum).

24 1.3 SUBMITTALS

25 A. Shop Drawings:

26 1. See Specification Section 01 33 00 for requirements for the mechanics and administration of 27 the submittal process.

28 2. Fabrication and/or layout drawings:

29 a. Schematic drawing of gas system showing major components and corresponding initial 30 pressure settings.

31 b. Schematic to include tag numbers assigned to each component by Contract Documents.

32 3. Product technical data:

33 a. Acknowledgement that products submitted meet requirements of standards referenced.

34 b. Manufacturer's installation instructions.

35 c. Calibration constants and pressure settings for devices requiring settings.

36 1) Calibrate settings using certified manometer.

37 B. Contract Closeout Information:

38 1. Operation and Maintenance Data:

39 a. See Specification Section 01 33 04 for requirements for the mechanics, administration, 40 and the content of Operation and Maintenance Manual submittals.

41 1.4 SYSTEM DESCRIPTION

42 A. The components described in this Section shall be supplied by one (1) manufacturer and when 43 interconnected with piping constitute a complete digester gas control system.

44 1. Each component is to be provided to integrate with other components for a complete 45 operating system.

46 2. Match the digester gas control system to all external devices using digester gas.

Paul Heerbrandt Cross-Out

DIGESTER GAS EQUIPMENT

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1 PART 2 - PRODUCTS

2 2.1 ACCEPTABLE MANUFACTURERS

3 A. Acceptable Manufacturers listed below. Only the manufacturers listed are approved for this 4 project, no alternate manufacturers will be considered.

5 1. Varec.

6 2. Groth.

7 2.2 MANUALLY OPERATED DRIP TRAPS

8 A. Design Criteria:

TAG # CAPACITY LOCATION

DT-01 6 quart Gas safety room

DT-02 6 quart Digester Equipment Building Boilers

11 B. Fabrication:

12 1. Manually operated drip traps 1 IN NPT inlet and outlet connection and a 6 quart storage 13 capacity.

14 2. Rotating disc type drip traps with an air inlet port to permit free flow of condensate from 15 bowl when draining.

16 3. Gas cannot exit while draining or revolving operating handle.

17 4. Cast aluminum unit with stainless steel shaft and springs.

18 5. Working pressure: 5 psig.

19 6. Pipe discharge from trap to nearest equipment or floor drain.

20 2.3 FOAM SEPARATORS

21 A. Design Criteria:

TAG #

SIZE

INLET/OUTLET GAS FLOW LOSS (MAX)

FS-01 8 IN 15,000 scfh 0.2 IN WC

FS-02 8 IN 15,000 scfh 0.2 IN WC

23 B. The foam separator shall operate by means of a continuous spray wash of water. The biogas 24 must rise vertically past an internal baffle located in the center of the unit. The foam separator 25 shall be a cylindrical tank 24-in diameter. The tank shall be constructed with 1/4” thick, welded, 26 316L stainless steel. Each separator shall be provided with ANSI 150 FF flanged connections.

27 C. Each tank shall remain gas tight to maximum operating pressure of 18-in WC. Each tank shall be 28 provided with a multiple spray system. The nozzles shall be 3/8” in 316 SS construction and 29 rated for 40 psi pressure with 2 gpm water flow at 2 psi supply pressure. Nozzles shall be spaced 30 on the pipe sections so as to completely cover the base area of the tank. Internal pipe sections 31 shall be constructed of stainless steel.

32 D. Each tank shall be provided with float-operated high and low level switches with termination 33 wiring in an explosion proof junction box.

34 E. A stainless steel bodied, double window, rotor type sight flow indicator shall be provided for the 35 4” operating overflow line of each separator.

36 2.4 ACCUMULATORS

37 A. Design Criteria: Condensate and sediment accumulators meeting the following:

DIGESTER GAS EQUIPMENT

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TAG #

SIZE

INLET/OUTLET GAS FLOW LOSS (MAX)

ST-01 8 IN 15,000 scfh 0.2 IN WC

ST-02 8 IN 15,000 scfh 0.2 IN WC

2 B. Fabrication:

3 1. Unit constructed from fabricated steel with flanged end connections.

4 a. Minimum storage capacity: 6 GAL of sediment and 6 GAL of condensate.

5 b. Tangential inlet nozzle to cause a circular motion of gas entering accumulator.

6 2. Piping connections shown on Drawings.

7 3. 1 IN NPT blowout connection, 1 IN NPT drip trap connection, and 3/8 IN NPT connections 8 for sight glass.

9 a. 1/2 IN Pyrex glass tube sight glass with two (2) isolating valves to permit cleaning.

10 b. Guard rods to protect glass tube and drain cock on lower valve.

11 4. Removable top cover for interior access and an inspection pipe for content level 12 measurements.

13 2.5 FLAME ARRESTERS

14 A. Design Criteria: Flame arresters meeting the following:

TAG #

INLET/OUTLET

SIZE

MAXIMUM GAS

FLOW BASE PRESSURE

MAXIMUM

PRESSURE

LOSS

FA-001 8 IN 15,000 scfh 10 IN WC 0.5 IN WC

FA-002 8 IN 15,000 scfh 10 IN WC 0.5 IN WC

17 B. Fabrication:

18 1. Flame arresters with ASME B16.1, Class 125 flanged end connections and working 19 pressure of 10 psig.

20 2. Aluminum housing.

21 3. Bank assembly:

22 a. Aluminum material.

23 b. Easy removal from housing for inspection and cleaning.

24 4. Net free area through bank assembly:

25 a. Not less than four (4) times connection size.

26 b. Construct grids of bank as individual corrugate stamped and rectangular shaped sheets.

27 c. Arrange for individual removal.

28 d. Horizontal or vertical configuration as indicated on Drawings.

29 2.6 PRESSURE RELIEF-FLAME TRAP ASSEMBLY

30 A. Design Criteria: Pressure relief flame trap assemblies meeting the following:

TAG #

INLET/OUTLET

SIZE

MAXIMUM GAS

FLOW

BASE

PRESSURE

MAXIMUM

PRESSURE

LOSS

PR-901 8 IN 15,000 scfh 1.5 IN WC 10 IN WC

33 B. Fabrication:

34 1. ASME B16.1, Class 125 flanged end connections.

35 a. Unit to include both a pressure relief section and a flame trap section.

36 2. Pressure relief portion:

DIGESTER GAS EQUIPMENT

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1 a. Back pressure regulator valve actuated by a spring loaded diaphragm.

2 b. Include a spring barrel with a glass enclosed pointer and scale to indicate relief pressure 3 setting.

4 c. Unit to permit setting adjustments without disassembling the diaphragm housing.

5 d. Cast aluminum unit with stainless moving parts and spring and synthetic rubber fiber 6 reinforced diaphragm.

7 e. Setting range: 2 to 12 IN WC.

8 f. 1/2 IN NPT connections for gas pressure sensing tap and atmospheric vent.

9 3. Flame trap portion:

10 a. Cast aluminum.

11 b. Bank assembly: All aluminum construction.

12 c. Easy removal for cleaning.

13 d. Net free area through bank assembly: Minimum of four (4) times inlet connection size.

14 e. Construct grids of bank individual corrugate stamped and rectangular shaped sheets.

15 f. Arrange for individual removal.

16 C. Controls:

17 1. Interconnect (functionally) pressure relief regulator and flame trap by a thermal shut-off 18 valve assembly which will automatically close the regulator by applying full upstream gas 19 pressure on the top of the diaphragm housing in the event a fusible element is released due 20 to gas temperature reaching 260 DegF at the flame trap outlet.

21 2. Fusible element replaceable without disassembling the valve.

22 D. Spare Parts for Each Size of Pressure Relief-Flame Trap Assembly:

23 1. Fusible elements: Four (4) each.

24 2. Diaphragm assembly: One (1) each.

25 3. Springs: One (1) set.

27 2.7 WASTE GAS BURNER

28 A. Design Criteria: Waste gas burner meeting the following:

TAG # INLET SIZE MAXIMUM GAS FLOW

PRESSURE

LOSS

PILOT

SUPPLY

B-001 6 IN 30,000 scfh 0.5 IN WC 0.5 IN WC

31 B. Fabrication:

32 1. Burner with ring type pilot that develops a flame curtain completely surrounding the gas 33 nozzle.

34 a. Baffles in the ignition chamber to direct digester gas through the curtain flame.

35 b. Shutter-type air-gas mixture adjustment.

36 2. A pedestal, insulated internally, enclosing the pilot gas line and digester gas line.

37 a. Base plate on pedestal suitable for mounting on concrete base support.

38 3. 1/2 IN NPT connection for pilot gas.

39 a. Pilot observation and igniting port on ignition chamber.

40 4. Burner: Steel with heat resistant iron alloy ignition ring, cast iron cover and frame of pilot 41 ignition port and stainless steel orifices of pilot gas supply.

42 5. Secondary stack:

43 a. Integrally mounted to the burner.

44 b. Schedule 10, Type 304 stainless steel pipe.

45 c. Spacing suitable to sustain flame in high wind conditions.

46 6. Automatic, electric, pilot igniter for each burner.

47 a. Igniter suitable for operation using 120 V, 1 PH, 60 Hz power supply.

48 7. Sense flame condition using an optical type flame sensor not in direct contact with the 49 flame.

DIGESTER GAS EQUIPMENT

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1 a. Sparking type ignition with replaceable electrodes.

2 8. Cables and other heat sensitive devices properly shielded and enclosed.

3 C. Controls:

4 1. In the automatic mode, unit will continually check for pilot flame.

5 2. Upon loss of flame, unit will automatically restrike the flame.

6 3. If a flame is not ignited, the unit continue to strike for a preset time period.

7 4. If, at the end of this time period flame is still not ignited, the unit will shut down and an 8 alarm activated.

9 D. Spare Parts for Each Size of Burner:

10 1. Spark electrodes: Two (2) sets.

11 2. Optical sensor: One (1) each.

13 2.8 DUAL COMBINATION PRESSURE/VACUUM RELIEF VALVE AND FLAME

14 ARRESTORS MOUNTED ON SAFETY SELECTOR VALVE

15 A. Acceptable Manufacturer:

16 1. Varec: 2 Series 5810B valves mounted on SSV valve.

17 2. Groth 2 Model 1200A/7618 valves mounted on 8800SDV valve.

19 B. Design and Fabrication:

20 1. Materials:

21 a. Low copper cast aluminum valve body and stainless steel trim.

22 b. Low copper cast aluminum flame arrestor housing with low copper 23 aluminum extensible bank assembly flame and stainless steel sheets.

24 2. Pressure relief lead pallet weights for adjustment in increments of 1/4 IN water column.

25 3. ASME B16.1, Class 125 FF flanged connections.

26 4. Insulating jackets:

27 a. Provide each assembly with insulated jacket to prevent freezing 28 b. Suitable for a temperature range of -40 to 220 DegF.

29 c. Insulated jacket constructed with silicone impregnated woven glass cloth lining with 30 a 1 IN thick, 6 LB density fiber glass insulating material.

31 d. Jacket to provide firm support to insulation preventing from shifting.

32 e. Insulated jacket designed to provide uniform heat retention.

34 C. Schedule:

TAG # INLET/OUTLET

SIZE

MAXIMUM

GAS FLOW

RELIEF

PRESSURE

VACUUM

PRESSURE

MAXIMUM

PRESSURE

DROP

PVRV 1 10 IN 15,000 scfh 11 IN WC 2 IN WC 0.5 IN WC PVRV 2 10 IN 15,000 scfh 11 IN WC 2 IN WC 0.5 IN WC

35 2.9 BACK PRESSURE CHECK VALVE

36 A. Design Criteria: Back pressure relief valves meeting the following:

TAG # INLET/OUTLET GAS FLOW

MAXIMUM

PRESSURE

LOSS

CV-01 8 IN 30,000 scfh 0.8 IN WC

39 B. Fabrication:

40 1. Back pressure check valves of heavy cast aluminum construction with removable seat ring 41 and stainless steel hinge pin.

42 2. Removable cover to provide access to seat ring and pallet.

DIGESTER GAS EQUIPMENT

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1 3. ASME B16.1, Class 125 flanged connections.

2 2.10 MANOMETERS

3 A. Design Criteria: Manometers meeting the following:

TAG # PRESSURE RANGE

PD-901 0-15 IN WC

B-902 0-3 psi

6 B. Fabrication:

7 1. U-tube type manometers calibrated to read in inches and tenths of water column.

8 2. Units with heavy wall annealed glass U-tube protected on three (3) sides by rigid steel 9 channel body.

10 3. Red mineral oil indicating fluid.

11 a. Fluid specific gravity of 1.0 compared with water.

12 4. Large bore U-tubes allowing for an essentially flat meniscus regardless of indicating fluid 13 used.

14 a. Easy removal of U-tube for cleaning or replacement without disturbing piping.

15 5. Mount manometers on common stainless steel panel designed for wall mounting with edges 16 extending to wall.

17 a. Panel:

18 1) Minimum 10 GA, Type 304 stainless steel.

19 2) Stainless steel attachment hardware.

20 3) Mount stainless steel isolation valves on panel and common atmospheric vent.

21 2.11 FLAME CHECKS

22 A. Design Criteria: Flame checks meeting the following:

TAG # LOCATION SIZE

FC-901 Manometer Vent 1/2 IN

25 B. Fabrication:

26 1. Flame check with NPT end connections.

27 2. Suitable for both digester gas and natural gas service.

28 3. Design housing similar to pipe union to permit easy removal for inspection and cleaning.

29 4. Construct union housing of cast aluminum.

30 5. Provide element constructed of aluminum compressed woven wire.

31 2.12 COVER POSITION INDICATOR (GAGEHEAD TYPE)

32 A. Design Criteria: Gagehead type cover position indicators meeting the following:

33 B. Fabrication:

34 1. Indicate cover position in feet, tenths and hundredths by counter located in gagehead.

35 a. Counter movement: Simultaneous with cover movement.

36 b. Calibrate counter to read zero when cover is resting on corbels.

37 c. Protect counter by a tempered glass window built into the gagehead housing.

38 d. Vent counter compartment to atmosphere.

39 2. Power working mechanism of gagehead by a negator-type motor completely enclosed 40 within a sealed, weatherproof housing meeting requirements for NEMA 4 rating.

41 a. Actuate mechanism by combination perforated tape and 1/8 IN stainless steel cable 42 connected directly to the digester cover.

43 b. Enclose tape and cable in stainless steel pipe conduit and provide weatherproof 44 enclosed sheave elbows and conduit.

DIGESTER GAS EQUIPMENT

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1 3. Gagehead and elbow housing:

2 a. Cast aluminum.

3 b. Aluminum and stainless steel gagehead working mechanism and stainless steel sheaves 4 in aluminum elbows.

5 c. Conduit constructed from stainless steel.

6 4. Teflon or Oilite bearings for all moving parts and stainless steel shafts.

7 5. Accommodate electrical position transmitted for remote reading equipment without 8 gagehead modification or removal from service.

9 C. Controls:

10 1. Position transmitter that converts movement in a proportional 4-20 mA DC signal.

11 2. Transmitter mounted in gagehead in a sealed enclosure meeting NEMA 4 requirements.

12 3. Transmitter suitable for operation using 120 V, 1 PH, 60 Hz power supply.

13 4. Place a desiccant in the transmitter housing after unit is installed.

14 D. Limit Switches:

15 1. Limit switches integrally mounted to gagehead.

16 2. Limit switches are totally enclosed NEMA 4 construction.

17 3. High limit switch to activate when top of cover is within 6 IN of the cover stop.

18 4. Lower limit switch to activate when cover is 6 IN above corbels.

19 5. Operation of limit switches is independent from position transmitter and suitable for 120 V, 20 1 PH, 60 Hz power supply.

21 PART 3 - EXECUTION

22 3.1 INSTALLATION

23 A. Pipe insulation.

24 B. Insulate sludge and gas piping which is exposed to ambient conditions below 40 DegF.

25 1. Use minimum 2 IN thick insulation with aluminum jacket in compliance with Specification 26 Section 40 42 00.

27 3.2 FIELD QUALITY CONTROL

28 1. Instruct Owner' personnel per Section 01 75 00 at jobsite on operation and maintenance of 29 the grinder equipment.

31 END OF SECTION