PART 1 GENERAL
Oil-fired multi-stage waste incinerator of pyrolytic type shall be installed complete with interconnecting flue gas ductwork between the incinerator and the chimney outlet.
The unit shall be manufactured in accordance with the latest ASME code, BS and DIN standards.
The waste disposal shall be environmentally acceptable and the incineration emission shall comply with the admissible emission limits (international EC-Standards). The visibility of flue gases shall not exceed one Ringelmann. The waste shall be completely burnt and the content of un burnt organic matter of the ash shall not exceed 3%.
The unit shall allow for a minimum of 2.0 seconds retention time.
1.2 QUALITY ASSURANCE:
A. Coordinate the entire assembly of incinerator, stack, controls, fuel supply.
B. Provide written certification that the entire assembly has been coordinated to achieve the required performance and to provide the required features.
C. Equipment, installation, and operation shall conform to NFPA 82. Where conflicts exist between NFPA 82 and this specification, this specification shall govern.
A. Submit in accordance with Section 01 33 23, SHOP DRAWINGS, PRODUCT DATA, AND SAMPLES.
1. Arrangement, description of construction, and outline drawings of incinerator and accessories showing clearances and dimensions.
2. Predicted performance including burn time based on waste composition specified.
3. Calculation of secondary chamber retention time.
4. Piping and stack connection locations and sizes.
5. Technical data including temperature rating and arrangement of refractory and insulation.
6. Weights of unit and loading diagram of foundation. Evidence that contractor has coordinated support requirements with foundation design.
7. Recommended anchorage to foundation. Seismic requirements apply. Submit calculations by professional engineer.
8. Predicted external surface temperatures.
9. Certified test report on performance of similar unit burning waste types which has composition similar to Article, PROJECT CONDITIONS, this specification:
a. Overall burn time and weight reduction.
b. Waste quantity and composition per batch.
c. Emissions in all categories specified in PART 2.
d. Auxiliary fuel use.
10. Catalog data on burners, sound attenuators, fuel trains, motors.
11. Fuel requirements: Flow rate, pressure at inlet to fuel train.
12. Full load power, efficiency, and power factor of all motors greater than one horsepower.
13. Electrical service requirements for all motors and controls.
14. Predicted sound level of all systems.
15. Schematic diagrams of control systems. Catalog cuts on components of control and instrument systems. Description of operation of control system.
16. Arrangement and location of control panels.
C. Stack System:
1. Drawings showing system arrangement and dimensions.
2. Weights of subassemblies.
3. Design, construction, pressure and temperature limitations of entire system including expansion joints and dampers.
4. Support point locations and loads for entire system.
1.4 APPLICABLE PUBLICATIONS:
A. The publications listed below form a part of this specification to the extent referenced. The publications are referenced in the text by basic designation only.
B. ASTM International (ASTM):
C401 91 (2005) Standard Classification of Alumina and Alumina-Silicate Castable Refractories
C612 04 Mineral Fiber Block and Board Thermal Insulation
C. National Fire Protection Association (NFPA):
70 07 National Electrical Code
82 04 Incinerators and Waste and Linen Handling Systems and Equipment
D. Underwriters Laboratories (UL):
50 07… Enclosures for Electrical Equipment
PART 2 PRODUCT
2.1 INCINERATOR INSTALLATION
A. The incinerator shall consist of a low temperature carbonizing changer (primary chamber) in which the waste components are converted into gas by heat which is produced through incomplete combustion as the result of a deficiency of air, and a gas reactor (thermal reactor) in which the gas is burned with a controlled excess of air.
B. The incinerator shall be equipped with water injection nozzle connection. If the temperature in the primary chamber should rise too high (normal temperature between 300 and 800C) during the operating time, the automatic water injection shall be activated to decease the temperature.
C. The incinerator shall have the following features and facilities:-
a- Fuel oil grade No. 2 (diesel oil) fired burners 220V, 50 Hz, single phase 4 wire electricity supply electric motors insulated to Class “F” suitable for operation at 50C ambient temperature.
b- The incinerator to be fully assembled wired and logic function tested in the factory, prior to dispatch.
c- One high flue gas temperature indicator/alarm to provide an audio/visual warning in the event of high flue gas temperatures occurring in two stages:-
d- First stage audible alarm, second stage incinerator shutdown, with one voltage free contact for connection to a remote alarm system.
e- Flexible wire control linkages to bring under fire air, overfire air and burner slide plate control to front of incinerator.
f- One fire protection system, comprising fusible links over burners, deadweight fire valve, electrically interlocked with incinerator controls.
g- Special feeding door with thermal lock to protect the operator from accident.
h- One set of cleaning tools.
i- Two sets of comprehensive written instructions.
D. The incinerator shall consist of a low temperature carbonizing changer (primary chamber) in which the waste components are converted into gas by heat which is produced through incomplete combustion as the result of a deficiency of air, and a gas reactor (thermal reactor) in which the gas is burned with a controlled excess of air.
E. The incinerator shall be equipped with water injection nozzle connection. If the temperature in the primary chamber should rise too high (normal temperature between 300 and 800C) during the operating time, the automatic water injection shall be activated to decease the temperature.
F. The incinerator shall have the following features and facilities:-
– Fuel oil grade No. 2 (diesel oil) fired burners 220V, 50 Hz, single phase 4 wire electricity supply electric motors insulated to Class “F” suitable for operation at 50C ambient temperature.
– The incinerator to be fully assembled wired and logic function tested in the factory, prior to dispatch.
– One high flue gas temperature indicator/alarm to provide an audio/visual warning in the event of high flue gas temperatures occurring in two stages:-
First stage audible alarm, second stage incinerator shutdown, with one voltage free contact for connection to a remote alarm system.
– Flexible wire control linkages to bring under fire air, overfire air and burner slide plate control to front of incinerator.
– One fire protection system, comprising fusible links over burners, deadweight fire valve, electrically interlocked with incinerator controls.
– Special feeding door with thermal lock to protect the operator from accident.
2.2 PRIMARY CHAMBER
A. The chamber shall consists of a welded steel shell of minimum 6mm thickness plate reinforcing strips and connections for primary air supply, start-up burner, thermal reactor, water injection and all necessary measuring probe sockets.
B. The entire chamber, including all the connections shall be lined with a composition of castable hot face refractory suitable for a continuous service temperature of 1500 deg. C. This lining shall be separated from the steel construction by a second layer of insulation. Heat resistant cast steel plates with many fine holes shall be lied over the refractory lined floor of the unit with a space between the two.
c. The chamber shall be externally primed and sprayed with a silicone enamel paint.
2.3 THERMAL REACTOR
A. The reactor shall consist of welded cylindrical steel sections of minimum 9.5mm thickness plate.
B. The whole chamber shall internally be constructed with a refractory lining.
C. The chamber shall be provided with connection for the low temperature carbonization gas intake, the flue gas outlet, the secondary and tertiary air supply, the reactor burner and all the required measuring probes.
D. Externally the reactor shall be primed and sprayed with a silicone enamel paint.
2.4 FLUE GAS DUCTWORK & CHIMNEY
A. The incinerator shall be provided with a range of interconnecting ductwork between the thermal reactor outlet and the inlet of the chimney. This ductwork shall consist of refractory lined tubes and high temperature resistant tubes made from rolled sheet steel of minimum 3mm thickness, welded along the length.
B. The standard chimney shall be made of carbon steel plates of minimum 3mm thickness.
Cooling air inlet gap shall be provided at the end of the refractory lined tube on the standard chimney.
C. The individual chimney sections shall have flanges on both sides.
D. All sections shall be primed and sprayed with zinc dust enamel paint.
E. Support wires shall be provided on chimney stacks.
F. The following shall be located within ductwork run:-
1. Mounting tubes for optical smoke density instrumentation.
2. Flexible expansion compensator.
3. A connection for a chrome/alum. Thermocouple, which is an integral part of the flue gas temperature indictor/two stage alarm system.
2.5 ACCESS DOORS
A. These shall be hinged from the front plate of the primary combustion chamber and shall comprise
1- A full width access/de-ashing door normally retained in the closed position by two handwheel clamps.
2- A smaller waste charging door hinged from and located in the main door. This door shall have a minimum of 500 mm. x 500 mm. aperture and be normally retained in the closed position by means of quick release latch.
3. A viewing port, so constructed that the observation/protective glass is capable of being cleaned whilst the incinerator is in operation, and located in the waste charging door, to allow the operator to safely observe the progress of combustion.
4. Each door shall be fabricated from mild steel and be internally lined to the same standards as the combustion chambers.
2.6 BURNERS AND BURNER CONTROLS
A. A single burner, suitable for operation on fuel oil shall be mounted on each combustion chamber.
B. The burners shall comply with the requirements of BS 799 or DIN Standards. Each shall be the packed type and incorporate automatic stop/start programmed timer control, flame failure equipment and ignition failure equipment to close off the fuel supply in the event of malfunction.
C. Each burner shall be designed and mounted for ease of access and so that they may be fully maintained from outside the combustion chamber. The burners shall be mounted so that waste cannot block the flame ports.
D. Start-up Burner
a. The purpose of the start-up burner is to ignite waste materials and to maintain the prescribed minimum temperature in the primary chamber. It shall be mounted in the lower part of the primary chamber.
b. The start-up burner shall function automatically when:-
– Pre-heating is completed, or after reaching the adjustable minimum temperature in the thermal reactor.
– The temperature in the primary chamber has dropped below the adjustable minimum value (e.g. 300C). This can occur when a lot of damp waste material is to be combusted.
– The start-up burner shall be of one-stage burner with pre-ventilation, working on the principle of an oil atomizer for diesel oil, consisting of:-
– Fan housing with adjustable air intake.
– Air closure damper with actuating drive
– Burner tube with burner connection and insulating flanges
– Burner plate with automatic oil firing sequence control, ignition transformer
– Electric nozzle rod with quick closing gate valve, electrode block, baffle plate.
E. The mounting point of the waste ignition burner shall be fitted with a manually operated sliding closure plate to protect the burner head when the flame is not in use. The slide plate shall be interlocked with the burner ignition controls to provide operation of the burner when the slide plate is not in the fully open position.
The integral burner air fan shall be wired for continuous running.
F. Reactor Burner
The purpose of the reactor burner is to ignite low temperature carbonization gases and to maintain the prescribed minimum temperature in the thermal reactor at all times but mainly during periods when the energy content of the carbonization gases is low (pre-heat, post combustion phase). It shall be mounted in the entrance area of the thermal reactor.
The reactor burner shall modulate between partial load and full load and automatically function when:
– The temperature in the thermal reactor drops below the adjustable minimum operating value (e.g. 1000C) (full load)
– The temperature is over the minimum and under the maximum required temperature (e.g 1150C) of the thermal reactor (partial load).
When switching off, only the solenoid valve for the fuel supply closes, the burner fan stays on to cool and protect the burner head.
The reactor burner shall be modulating burner with pre-ventilation working on the principle of an oil pressure atomizer with return nozzle for diesel oil, consisting of:
– Fan housing with high-powered fan and cover
– Electric motor
– Oil pressure pump with built-in oil pressure controller
– Burner nozzle rod with return nozzle and baffle plate
– Coupled control with servomotor, rate controller, regulating segment and air valves
– Electromagnetic shut-off dampers
– Burner tube with flame pot, burner connection and insulation flange
– Electrical high voltage ignition with ignition transformer and ignition electrodes
In the control panel:
– Oil firing sequence control automation relay.
2.7 CONTROL UNIT
A. The entire processing cycle and the combined effect of the individual components of the incinerator shall be achieved by a central control unit.
B. The control panel shall consist of a standardized sprayed sheet steel shell with doors and the necessary mounting supports and contains all the devices such as relays, time switch, safety device, contactors, regulator, display devices, recorder, selection, on, off and main switches, and indicator lamps required for the control, regulating and registration.
PART 3 EXECUTION
A. Equipment Access Openings: Arrange all equipment and piping to allow access to openings without disassembly of equipment or piping. Provide space which permits full opening of all doors, panels, and other access openings.
B. Operating Space: Do not reduce or alter personnel working spaces shown except with prior approval of Resident Engineer.
C. Fuel Oil System: Coordinate set pressure of house fuel oil system with requirements of burner mounted pumps. Do not exceed inlet pressure limitations (typically 14 kPa or 2 psi or less), or suction lift capabilities of burner mounted pumps.
D. Pipe all drains to floor drain.
E. Anchor all equipment to building floor or structure as shown or as recommended by manufacturer with allowance for thermal expansion as necessary.
F. Control and Instrument Panel: Rigidly attach enclosure to structural element of the building. Locate panel so that all control switches and indicators are within 1700 mm (5.5 feet) of the floor and are located alongside the area where personnel will be loading the unit.
G. Clean interior and exterior of all equipment before placing in service.
H. Initially operate incinerator at firing rates and time periods recommended by the manufacturer of the refractory to provide proper curing of the refractory. Provide printed curing instructions from refractory manufacturer at the site prior to first start up.
I. Personnel Protection for High Surface Temperature: If incinerator has surface temperatures exceeding 40 degrees C (70 degrees F) above ambient, provide removable chain barricades mounted on 1070 mm (3 1/2 feet) high removable steel posts spaced 1200 mm (four feet) on centers. Locate barricade at least 900 mm (three feet) away from hot surfaces. Provide yellow polyethylene chain with removable hooks at each post. Provide sign attached to each chain reading, “Caution, High Temperature”.
3.2 INSPECTIONS AND TESTS:
A. General: Demonstrate to the Department of Veterans Affairs that all equipment complies with requirements. The Contracting Officers Technical Representative (COTR)/Resident Engineer (RE), or their representative shall witness all tests. Representatives of the pollution control authority that has jurisdiction shall also witness emissions tests. Provide two weeks advance notice to the COTR/RE of all testing. Pretest all items prior to the final testing that is witnessed by the COTR/RE.
B. Condition of Equipment after Delivery, Rigging, Placement: After setting equipment on foundations, and prior to making any connections to equipment, the Contractor and COTR/RE jointly shall inspect interior and exterior for damage. Correct all damage by repair or replacement to achieve a like new condition.
C. Incinerator Tests:
1. Reduction of Waste:
a. Test shall be conducted by factory authorized representative of incinerator manufacturer.
b. Demonstrate required weight reduction of specified waste. Waste shall be fed in a single batch to the unit. After termination of manufacturer’s predicted burning period, inspect and weigh the residue.
c. Emissions testing may be deleted if not required by state or local authorities. List all additional tests required by state and local emission authorities.
a. Test shall be conducted by independent testing organization provided by Contractor which has a minimum of three years experience in emissions testing and which has been approved by the pollution control authority that has jurisdiction.
b. Conduct tests during the reduction of waste test specified above.
c. Test methods must comply with EPA Reference Method 5, 40 CFR 60, Appendix B, “Determination of Particulate Emissions from Stationary Sources”.
d. Demonstrate that incinerator complies with specified emission limits.
3. Sound Levels: Demonstrate conformance to sound level limitation.
4. Report: Furnish complete written report (three copies), which includes test data, calculations, results compared with requirements, list of personnel, and other pertinent information. Furnish report within three weeks of test date.