General Specifications — Previous Page

NOx EXHAUST GAS SCRUBBERS
Scrubbers shall be designed for specified collection removal efficiency of air contaminants arising from the process equipment listed herein. Collection efficiencies shall apply to the unit as a whole, including mist eliminators downstream of the packing. Overall mass collection efficiency shall be ____% or better at design gas flow.

Field pilot system and stack testing services available. These costs are applicable to purchase of ßeta NOx 2000™ system.

NOTE: Consult factory for field/pilot testing services terms and conditions.

Corrosion Resistance:

  1. Scrubbers, including all internals and appurtenances, shall be completely resistant to chemical corrosion from the process equipment listed herein.
  2. Scrubber housing shall be constructed of Type II, Grade I, high-impact polyvinyl chloride (PVC) conforming to ASTM D 1784-69 Cell 1433D. Outdoor installation shall be white PVC for UV resistance, polypropylene, or FRP/PVC, fiberglass with PVC liner.

Base: Each scrubber shall be complete with a corrosion-resistant coated steel base of sufficient strength to make the unit self supporting when wet.

Scrubber Piping:

  1. Furnish all scrubber internal piping necessary for recirculation of scrubber solution such that installer need only make single external piping connections for scrubbing solution supply and return. Piping shall be polyvinyl chloride (PVC). Wherever possible, piping shall be installed at the factory. Interior piping to be removable through access doors for maintenance.
  2. Spray nozzles shall by full cone non-clogging type of sufficient quantity to insure complete coverage of the packing face. On horizontal scrubbers, overhead spray headers shall be provided to prevent channeling of the gas stream.

Pumps: Recirculation pumps shall be vertical sealless centrifugal chemical duty type, constructed of materials completely resistant to corrosion from all contaminants listed herein are standard. Pump motors shall be single-speed, NEMA Design B, Class-B insulated, 230/460 volts, 3-phase, 60-hertz. All external pump and drive components shall be of corrosion-resistant construction or otherwise epoxy-coated. Pumps shall be securely mounted to sump box or remote tank. Pumps shall be sized to handle a minimum of 40 feet of head on self-contained and 70 feet of head on remote recirculation systems. Horizontal ANSI B73.1 Type Recirculation Pumps are optional.

Remote Recirculation Tanks: If required, each scrubber will be furnished with a remote recirculation tank to be constructed of PVC, Polypropylene, PVC/FRP overlay, or FRP. Fittings will be provided on the tank for pump suction, overflow, and drain. Tanks shall be of sufficient capacity and structural rigidity for intended service. Tank freeboard above the overflow connection shall be of sufficient
volume to contain liquid volume suspended in supply and return pipes and scrubbers. Recirculation pumps shall be mounted on top of tank.

Fans:

  1. The fans shall have been tested and rated according to AMCA Standard 210 and ASHRAE Standard 51. They shall be certified by the Air Movement and Control Association (AMCA) and shall be licensed to bear the AMCA seal.
  2. All fan parts in contact with the airstream shall be resistant to attack by contaminants found in the exhaust air.

Scrubber Packing: The scrubber packing shall be resistant to corrosion from all contaminants specified. Packing shall be non-clogging, non-nesting and of such design and bed depth as to achieve certified collection efficiencies stated herein. Minimum surface area of packing to be 31 square feet per cubic foot.

Mist Eliminator: A mist eliminator shall be provided to effectively remove entrained water droplets prior to leaving the scrubber.

Access Panels: Removable access panels for packing removal, spray nozzles and mist eliminator maintenance shall be furnished. Transparent view parts to allow for inspection of packing and spray nozzles are also standard.

Flow Meter: A flow meter for indicating/adjusting fresh-water make-up will be furnished. Dwyer instruments Series RM that clearly indicates design flow on scale will be utilized.

Pressure Gauge: All Duall fume scrubbers are supplied with a pressure gauge to monitor pressure differential across the filter packing. The Duall specified gauge would be a Dwyer Instruments Series 2000 Magnehelic, or equal.

Options

  • Factory hydrostatic and pressure testing.
  • Pre-purchase stack testing for NOx.
  • Pre-purchase slip stream pilot scrubbing and performance testing.
  • CEM monitoring and chemical feed integration.
  • Performance testing.
  • ANSI horizontal recirculation pumps.
  • Auxiliary pump and fan systems.
  • Air diaphragm chemical feed pumps.
  • Ejector for draft inducement up to 10,000 SCFM.
  • PLC and operator interface.

Complete Electrical Control Systems

  • Integral chemical feed controls
  • Motor starter panels and/or MCC options.
  • Alarm system with interlocks.
  • NEMA 4 control cabinets.
  • Chemical usage and NOx charting or trending.

 

— Previous Page
 
Duall Division
1550 Industrial Drive, Owosso, Michigan 48867
Phone: 989-725-8184 Fax: 989-725-8188
E-mail: info@dualldiv.com
© 2006 Duall Division