THE NEED
Accurate, reliable measurement of H2S and SO2 in the tail gas from a Claus sulfur recovery plant is critical.
Unfortunately, tail gas analysis has historically been one of the most difficult applications because of common
problems with sample line plugging due to sulfur vapors present in the sample. DIRECT MEASUREMENT
AMETEK Western Research, the leader in tail gas analysis for over 25 years, is proud to present the Model
880-NSL (No Sample Line) tail gas analyzer. The Model 880-NSL uses field-proven UV techniques to accurately
monitor the H2S and SO2 concentrations in the tail gas. This compact, rugged, transmitter-style analyzer mounts
directly on your process pipe, eliminating sample line plugging. The 880-NSL is also equipped with anticlogging
blowback features that automatically initiate an air blowback of the analyzer should any internal fault
condition occur. In addition to these reliability-enhancing design features, the 880-NSL comes standard with an extraordinary longlife
lamp which will last for up to five years! Reliability is further enhanced as the detector assembly is solid state
with no moving parts. The analyzer is also provided with self-monitoring and self-diagnostic features including a
calibration filter for performing automatic span verifications. Both the Zone 1 and Class 1, Div 2 versions of the
Model 880-NSL are housed in weatherproof, stainless steel enclosures which are suitable for direct outdoor
installation in most parts of the world.
APPLICATIONS
••• Sulfur recovery tail gas analysis
– Claus process
– Claus with tail gas cleanup
– Claus with oxygen enrichment
SUPERIOR BENEFITS
• No Sample Line!
• Outdoor installation
• High reliability / low maintenance
• Fast response time
• Extraordinary lamp life
• Automatic zero and span check
• Hot water back-flush for salts removal (optional)
• Self-diagnostic and self-preservation features
PERFORMANCE SPECIFICATIONS
Methodology: Non-dispersive ultraviolet
Measurement Range: 0 to 1% SO2, 0 to 2% H2S, -1 to 1% excess
H2S typically (0 to 2% SO2 / 0 to 4% H2S optional)
Accuracy: H2S and SO2: ±2% of full scale
Sensitivity: ±0.15% full scale
Reproducibility: ±1% of full scale
Speed of Response: 90% in less than 15 seconds, typical
Sample Flow: 2 LPM typical
Ambient Temperature: -20OC to 50OC (-4OF to 122OF)
Utilities
Electrical: 120/240 VAC 50/60 Hz 720W, single phase
Instrument Air: 490 to 700 kPa (70 to 100 psig )
Steam Pressure:
For optional ball valve jacket: 515 to 690 kPa (75 to 100 psig)
For optional blow back: 210 to 345 kPa (30 to 50 psig)
Outputs
Three (3) 4-to-20 mA, self-powered, linear, 1200 ohms load
proportional to H2S, SO2, and either Excess H2S or Ratio
One (1) digital, System Alarm incorporates concentration,
overrange, system errors, and Watchdog alarm (30 Vac,
60 Vdc, 50 VA, maximum, resistive load)
One (1) digital, Data Valid Signal (30 Vac, 60 Vdc, 50VA, maximum,
resistive load)
RS-485 Serial Communication Port, half duplex, two-wire
Inputs
One (1) digital input for remote auto calibration, contact closure,
5 Vdc @ 2.5 mA
One (1) digital input for remote blowback, contact closure,
12 Vdc @ 100 mA
Note: Provide isolated contact closure only. Do not apply voltage.
Digital Communication: RS485 serial port. Remote dial-in
capabilities available with AMETEK Western Research software
Noise: ±0.5% full scale
Zero Drift: Less than ±0.5% of full scale in 24 hours through
periodic automatic zero standardization using instrument air
Calibration: Automatic with span filter, manually operated from the
controller
Process Sample Pressure: Not critical
Customer-Supplied Items: 2 in.-150 lbs. or DIN equivalent RF
stainless steel flange connection
Enclosure Material: 316 stainless steel
Approvals and Certifications
UL/CSA General Safety Requirements
UL/CSA Class I, Division 2, Groups A, B, C, and D
ATEX II 2 G, EEx p mde [ib] IIC T3
Complies with all relevant European directives
Physical Dimensions: (H x W x D): 950 x 1037 x 305 mm
(37.3 x 41 x 12 inch)
Approximate Weight: 115 kg (250 lbs.)