Beijing Qinglian Measurement and Control Technology Co., Ltd

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Beijing Qinglian Measurement and Control Technology Co., Ltd

Tel：18500242456
Email：sales@qingliancekong.com

Address: Inside Beijing Taixing Art Institute, Shuipo Village, Gaoliying Town, Shunyi District, Beijing

OMA Hydrogen Sulfide Online Analysis

AAI’s best-selling analyzer

Using the advanced NOVA II UV-Vis diode-array spectrophotometer, we can achieve full-spectrum monitoring, avoid component interference, eliminate measurement errors, and enhance accuracy.

The measurement range spans from as low as 0–10 ppm to as high as 0–100%, and the range can be adjusted at any time. It simultaneously measures up to four additional components.

High-intensity sample measurement flow cell that allows direct measurement of hot and humid samples. The sample does not come into contact with the analyzer, ensuring high safety.

The extractive sampling method offers a faster response time. With a solid-state design and no consumables, it features low maintenance costs.

Product Features

Performance

Fast, continuous readings T90 response time is less than 10 seconds. No false alarms Measure hydrogen sulfide concentration only in the absence of interference from other substances. Extremely wide dynamic measurement range It can maintain high accuracy even when the sample concentration varies significantly.

Safety and Reliability

Fully automated operation under unmanned supervision Automatic purging and zeroing function; optional remote automated control A Safer Hydrogen Sulfide Analyzer The sample never comes into contact with or enters the interior of the analyzer housing. Customize various alarm and communication outputs. 4-20mA analog output, MODBUS; HART, etc.

Flexibility

Can measure hydrogen sulfide concentrations across any range. From 0-10 ppm to 0-100% Samples that can directly measure heat/humidity The standard configuration can withstand 150° and 3,000 psi; higher configurations are available upon request. Can directly measure liquids or gases. Use the sample pretreatment system An additional 4 other components can be measured. Measure the concentrations of other components.

Maintenance cost

No consumable materials or reagents. In addition to purging with standard gas, Low maintenance requirements Simply require wiping the lenses once a month. Long-life xenon light source Average service life of 5 years Instrument with an all-solid-state structure Stands out among competitors due to the absence of moving parts.

Compatibility

Explosion-proof certificate Class I Div 1 & 2; ATEX; GOST... View certifications No-analysis cabin Can be installed directly outdoors.

Application fields

H ₂ S becomes as low as 10 ppm, it becomes toxic to humans; at 800 ppm, it is lethal. It also exhibits strong corrosive properties toward metal pipelines and equipment. Because of these effects, it has earned a notorious reputation among humans. When H ₂ When the concentration of S in the air reaches 4.3%, it becomes flammable; and at just 1 ppb, it produces an odor that both workers and residents find unbearable.

Hydrogen sulfide is abundantly present in fossil fuels and can be produced through various biochemical processes. To obtain clean, combustible fuels, prevent the formation of acid rain, protect pipelines from corrosion, and keep workers safe from hazards, it is essential to continuously monitor hydrogen sulfide concentrations.

Since 1994, thousands of OMA units have been installed in factories around the world, and OMA hydrogen sulfide has been proven to be successfully applicable in a wide variety of applications across different industrial sectors.

Technical concept

Monitoring Principle

The OMA online analyzer uses the principles of ultraviolet and visible spectroscopy to determine the concentrations of chemical components in a sample. The OMA system analyzes the absorbance of the sample across wavelengths from 200 to 800 nanometers, and the data is captured by a 1024-element photodiode array detector and transmitted to a processor for data analysis, yielding high-resolution absorption spectra.

Optical structure

The OMA process online analyzer uses a long-life xenon lamp as its light source to transmit signals that come into contact with the sample via a flow cell. This signal is emitted by the light source and transmitted through an optical fiber cable into the flow cell, where it interacts with the sample gas. Samples composed of various chemical substances exhibit unique absorption characteristics for light. The resulting light signal then exits the flow cell, travels back to the detector via another optical fiber cable.

Hydrogen Sulfide Absorption Spectroscopy Diagram

To detect the concentration of hydrogen sulfide, the OMA identifies the unique absorption spectrum of pure hydrogen sulfide and uses mathematical methods to separate and isolate the hydrogen sulfide absorption spectrum from that of the sample being measured. Based on Beer-Lambert’s law, the OMA correlates the unique hydrogen sulfide absorption spectrum with the actual hydrogen sulfide concentration.

User interface

AAI’s proprietary ECLIPSE software processes the acquired spectral data into actual concentration readings. On the touchscreen controller, the analyzer operator can easily switch between different interfaces—such as trend graphs, spectra plots, concentration readings, and more—and can independently and at any time set and adjust alarms, outputs, purge functions, zeroing, and other parameters.

Multi-component measurement

Most analyzers directly introduce the sample into the analyzer’s housing for measurement. However, if the sample is toxic, highly corrosive, or explosive, this could be extremely dangerous. The OMA design is unique: instead of introducing the sample into our analyzer, we guide the optical signal into the sample itself. The sample flows only through a flow cell and never comes into contact with the analyzer. The flow cell is connected to the analyzer via an optical fiber cable.

Technical Comparison

A Comparison of Four Relatively Common Hydrogen Sulfide Analysis Methods

	OMA Hydrogen Sulfide Analyzer	Lead acetate paper strip method	Tunable diode laser	Chromatography
Response time	Less than 10 seconds	From 20 to 180 seconds—the actual response time is determined by the hydrogen sulfide concentration.	Less than 10 seconds	5 to 10 minutes
The impact of moisture	The water has no absorbance from 200 to 240 nanometers.	None	The absorption of moisture can severely affect the measured wavelength.	None
Hydrogen sulfide concentration range	Measurements range from as low as 0–10 ppm to as high as 0–100%; users can adjust the measurement range at any time and as desired.	Suitable only for use with small measurement ranges; the paper strip reaches saturation at concentrations greater than 1000 ppm, requiring a titration dilution pretreatment system.	Designed for concentration ranges below 500 ppmv. Systems exceeding 500 ppmv will trigger an alarm and will not display any readings.	Wide
Simultaneously measure other substances	Can additionally measure four other substances simultaneously.	The special paper strip can only measure the concentration of its corresponding substance.	Each TDL device can measure only one substance.	Yes
Maximum sample pressure	Standard configuration: 3000 psig	The sample must be at standard atmospheric pressure.	Up to 20 psig	The sample must be at standard atmospheric pressure.
Maximum sample temperature	The standard flow cell can withstand high temperatures up to 150°C and features temperature compensation.	High	Extremely sensitive to temperature; temperature changes can cause reading errors. The temperature must not exceed 50° to 60°.	Low
Movable parts	None. All-solid-state structure	Yes. The paper tape often gets jammed.	None	There is
Consumable expenditure	Only the automatic purging and zeroing standard gas needs to be replenished. The xenon lamp light source has a service life of at least 5 years.	One roll of paper tape can last a month and must be manually replaced. The acetic acid solution needs to be replenished frequently.	Copper nano-washers need to be replaced annually. The internal liquid consumption is also quite high.	The carrier gas, chromatographic separation column, and detector all need to be replaced frequently.
Maintenance volume	Optical lenses need to be cleaned regularly—once a month is recommended, taking just over ten seconds each time.	The paper tape needs to be replaced every month, and it often gets clogged. When the system is overloaded, it has to be manually diluted.	Optical lenses need to be cleaned regularly.	It is well known that the maintenance workload is enormous.

Sample system

The OMA series analyzers can directly measure hot and humid samples, simplifying the sampling process. We have extensive experience in hydrogen sulfide analysis, and while many application principles are similar, actual conditions often vary significantly. Therefore, for projects that require it, we offer customized design of sample pretreatment systems or sampling systems tailored to our clients’ specific needs.

Optional models

OMA products of various models share the same electronic architecture, and their monitoring functions and performance are identical. The differences among these models lie in their external structural designs and the materials used, with the aim of meeting the diverse requirements of different applications.

Technical Parameters

The following technical specifications are based on the premise that all components and the sample system are supplied by AAI, and that the system installation has been approved by AAI. For technical specifications under other conditions, please consult AAI’s sales team directly.

General

Operating environment
Measurement principle	Dispersion Ultraviolet-Visible Spectrophotometry
Detector	nova II™ UV-Vis Diode Array Spectrometer
Spectral detection range	200–800 nm
Light source	Pulsed xenon lamp light source, with a service life of five years.
Signal transmission	600-micron core, 1.8-meter-long optical cable; other lengths available upon request.
Sample Preprocessing	Customized design for different applications
Analyzer calibration	Before leaving the factory, the instrument is calibrated using a standard gas that has been certified by the manufacturer; users do not need to calibrate it again. The system’s accuracy is ensured by an automatic zeroing function.
Reading verification	Quick and easy verification via standard samples and self-diagnosis functions.
Controller	Industrial controller equipped with an LCD touch screen and ECLIPSE™ operating software.
Data storage	Pure solid-state drive
Analyzer environmental conditions	Suitable for both indoor and outdoor use; no analysis cabin required.
Ambient temperature	Standard: 0 - 35 °C (32 - 95 °F)
	Optional: -20 to 55 °C (-4 to 131 °F)
	To avoid thermal radiation, it is recommended to install the analyzer under a sunshade when exposed to direct sunlight.
Sample temperature	Standard: -20 – 70 °C (-4 – 158 °F)
	Optional: When equipped with a cooling extension, the maximum temperature can reach up to 150 °C (302 °F).
	If the temperature exceeds 150 °C (302°F), please contact AAI.
Sample pressure	Standard flow cell: 206 bar (3000 psi)
	Insertion probe: 100 bar (1470 psig)
Power requirements
Electricity	85 - 264 VAC 47 - 63 Hz
Power consumption	45 watts
Output
Standard output	One measured substance corresponds to one 4-20 mA analog output (up to three channels are available; additional options available after upgrade).
	Two digital outputs correspond to alarm and pre-processing control.
Optional output	Modbus TCP/IP; RS-232; RS-485; Fieldbus; Profibus; HART;
Appearance features
Select the analyzer housing	OMA-300 Wall-Mounted
	OMA-206P Portable
	OMA-406R Rack-Mounted

Measurement parameters

Accuracy	Measuring hydrogen sulfide in liquids	Measuring hydrogen sulfide in gases
	The following are example measurement ranges; customized measurement ranges are also available. 0–100 mg/L: ±1% of full scale or 1 mg/L*	The following are example measurement ranges; customized measurement ranges are also available. Generally, accuracy increases as pressure rises. 0-10 mg/m ³ ±1% of full scale (pressure greater than 10 bar) 0–10 ppm (@1 bar): ±1 ppm (accuracy increases with increasing pressure); ±0.2 ppm (@5 bar) 0–100 ppm: ±1% of full scale or 1 ppm* 0–10,000 ppm: ±1% of full scale 0-100%: ±1% of full scale
	*Take the larger one as the standard.
Repetitiveness	±0.4% of full scale
Response time (T90)	Less than 10 seconds
Zero-drift	After the instrument is powered on, it can achieve an accuracy of ±0.1% within one hour and remain stable for 24 hours (under constant ambient temperature).
Lower Limit of Detection	0.14 ppm or 0.19 mg/m³

Certificate

The following are typical explosion-proof certificates; other types are also available:

Standard design	Non-explosion-proof
Offer optional	ATEX, IECEx, EAC, PESO, JPN, KTL
For other certificates, such as CSA, FM, etc., please contact your sales representative.