ATOM Instrument offers the most versatile Total Sulfur analyzers available. The ATOM SLA-1000 has the fastest analysis time of any commercially available analyzer allowing user-defined , multiple cycle averaging to improve analyzer performance. The analyzer operating software is both intuitive and user-friendly. In addition, the ATOM SLA requires only bottled air (no other gases needed for carrier or combustion) during normal operation and does not require installation in a shelter.
The ATOM SLA-1000 is an online process analyzer utilizing patented Excimer UV Fluorescence (EUVF) technology to measure Total Sulfur in a variety of refinery process applications.

Typical Applications for the SLA-1000 includes Total Sulfur measurement in:
- Diesel (including ULSD)
- Gasoline (including Tier-Ill)
- Reforming and lsomerization
- Other Refinery Grade Fuel
- Blending Operations
- Catalyst Protection
- Natural Gasoline
Excimer UV Fluorescence {EUVF) Provides Low Range Detection and Stability
The Model SLA-1000 is based on field-proven EUVF technology that is exceptionally stable and utilizes an excitation wavelength that achieves high detection sensitivity. The SLA-1000 is an excellent fit for applications in the 0-1O ppm range even at concentrations lower than 1 ppm. In addition, Excimer technology provides little to no Nitrogen interference compared to other UVF technologies. The SLA-1000 is designed for outdoor installation and use in harsh environments as may be required by applications within the petroleum and petrochemical industries.
Simplified Design Improves Reliability
Calibration and Validation routines are seamlessly incorporated into the ATOM operation software. The analyzer has a very fast response time to process changes (within 1 cycle), insuring proper process monitoring with fast-moving processes. The sample injection system design is simplified resulting in greater reliability and lower maintenance, for example, the sample valve only actuates once per cycle increasing lifetime. Finally, the analyzer results are insensitive to sample buildup or interference from oxygenates present in the sample stream.
Principle of Operation
The UV Fluorescence method is the most simple and practical low-level sulfur analytical technique. It has been widely used and proven over many years of use in industrial settings. This method involves the injection of a sample into a high-temperature oxidation furnace, converting all hydrocarbons into water (H20) and carbon dioxide (C02). Total sulfur contained in molecular-bound hydrocarbon species is oxidized at temperatures in excess of 1000°C into sulfur dioxide (S02) by the reaction:
R-SH + O2 → SO2 + CO2 + H2O
The furnace effluent containing these combustion byproducts is directed into a detection chamber where it is excited by high-energy, short-wavelength emission from the excimer source. The UV photons from the excitation source, transfer energy into the SO2molecule and raise its energy level to create back to their lower energy ground state releasing the absorbed energy as a secondary emission known as fluorescence.
SO2 + hv → SO2* → SO2 + hv’
Fluorescence emission is optically filtered to remove undesired wavelengths from excitation source and background scatter within the detector chamber. Detection of filtered fluorescence emission is accomplished using a Photomultiplier Tube and amplified by proprietary high sensitivity electronics.
Graphical User Interface (GUI)
The SLA software incorporates a user-friendly Graphical User Interface (GUI) designed to be both intuitive and easy to use. All aspects of analyzer operation are accessible from the Main toolbar utilizing drop-down menu screens. The home screen displays 3 user selectable digital readout and analog bar graphs updated in real-time from the analysis. Run Cycle Status and current timed events are also refreshed in real-time. Major system control elements are also incorporated in this home screen. The calibrate menu allows complete control of calibration and validation processes, including manual, auto calibration, and validation sequencing. Analytical results acquired during these events may be inspected at any time prior to subsequent calibrations.
All other menu screens such as Timed Events, Detector, Analog Output, Digital 1/0 and System Alarm Settings, allow the user to easily monitor or make changes to all aspects of analyzer control and operation. The GUI software also includes user setup and password security, as well as graphics plotting of real-time analysis data and display of historical settings.

Remote ATOM ACCESS®
The Analyzer Central Communication Ethernet Server Software allows an authorized user to access any ATOM analyzer on the facility network from an internal office or work station. After a successful security login, the network will initiate communication to the selected instrument of choice. Once connected, the instrument can be operated and interfaced with, just as if the user was standing directly in front of the instrument. Instead
of utilizing the analyzer touch screen, the remote connection keyboard and mouse are used for all interface requirements.
Speed of Analysis and Response Time
The ATOM SLA-1000 is specifically designed for high-speed analysis and fast response time. This feature enables more rapid, real-time measurements to be performed, allowing process events and changes to be monitored and quantified in a timely manner. Process variations and detail potentially obscured with slower responding analyzers, may be revealed or become more apparent. The cycle time is completely user-selectable although a 1DO-second cycle time is standard.
Low Concentration Total Sulfur Analysis
The SLA-1000 allows stable and accurate analysis at both high and low sulfur concentrations, even below 1 ppm, using the standard 100 second analysis cycle time. Any number of analysis up to 10 sequential results can be seamlessly averaged to provide a more consistent and reliable concentration measurement. In turn, this allows optimization of low range detection performance and analyzer response time for specific application requirements.
Most Compact Footprint
The following table allows direct comparison of size and occupied volume for the ATOM SLA-1000 vs current standard instrument packages. (Dimensions do not include the size of the mounting framework or stand.
Package 1 | Package 2 | ATOM SGA | |
Height | 45.00 inches | 43.48 inchs | 38.00 inches |
Width | 26.00 inches | 25.50 inches | 26.00 inches |
Depth | 30.00 inches | 18.75 inches | 12.00 inches |
Volume | 20.31 ft3 | 12.03 ft3 | 6.86 ft3 |
SPECIFICATIONS | ||
---|---|---|
Analytical Performance | ||
Measurement Method | Total Sulfur by Excimer UV Fluorescence (EUVF) | |
Measurement Range | 500 ppb- 10% (Application dependent) | |
Repeatability | 200ppb SD or ±2% of measured value, whichever is greater 100ppb SD with 5-min. averaging or ±2% of measured value, whichever is greater | |
Linearity | ±2% of full scale (Dynamic Range Dependent) | |
Response Tim Calibration | 99% (+) in one cycle (60-100 secs typical) | |
Calibration | Automatic or manual | |
Analog/Discrete Data Communications | ||
Analog Outputs Single | 4-20 mA DC (optional) | |
Alarm Outputs | One global dry contact triggered by one or more of the following: Power Failure, Loss of Purge, Low Oxidizer Pressure, Low Furnace Temperature. Other Alarms Incorporated and Available | |
Digital Data Communications | RS-485 or RS-422 Modbus (RS-232 or TCP/IP Ethernet Optional) | |
Local MMI (GUI) | 12" Touchscreen Computer with Embedded Windows 7 allows complete operation and control of all analyzer functions | |
Remote Interface | ATOM ACCESS allows complete control of SGA-1000 , including monitoring of analysis parameters and digital data values | |
Ultility Requirements | ||
Ambient Temperature | -20°C to +40°C (-4°F to +104°F) | |
Power | 120 VAC,50/60 Hz at 2200 watts | |
Instrument Air | 70 psig (4.8 bar), 5 SCFM, Oil Free, -40°C (-40°F) dew point | |
Zero Air Grade | 70 psig (4.8 bar), 200 SCCM | |
Physical Parameters | ||
Dimensions | 965.2 mm (38.0 in) high x 660.4 mm (26.0 in) wide x 304.8 mm (12.0 in) deep | |
Mounting | Wall or Unistrut Stand | |
Certifications | Built to NEC Class1,Div2, Group B,C,D CSA (optional) |