NHVOC-31 NMHC Continuous Monitoring System

NHVOC-31 is a continuous monitoring system for non-methane total hydrocarbons in exhaust gases uses GC-FID (gas chromatography-flame ionization detection) technique to monitor VOCs (volatile organic compounds) in real-time.

Classification:

Product Center

Environmental Monitoring

VOCs Online Monitoring System

Product Documentation:

Monitoring parameters:
- VOCs, NMHC, benzene series (benzene, methylbenzene, xylene), etc.
- Other customized parameters.

Details

This system is technologically advanced, stable, and reliable, featuring a high degree of automation and a wide monitoring range. It responds quickly and can transmit all monitoring parameters to industrial control software and user DCS systems. It also supports communication with environmental protection departments' data systems via data acquisition instruments. The system includes real-time data transmission and remote fault diagnosis, enabling unattended operation at the worksite.

Features

Designed for extreme conditions such as high temperature, high humidity, high concentration, and high dust environments, with a full heat tracing process from sampling to analysis to minimize sample loss and ensure data accuracy.
The sampling pipeline uses PTFE and inert metal with low adsorption properties, with an adjustable heating temperature of 120°C, effectively reducing sample loss due to pipeline adsorption.
The pre-treatment method complies with U.S. EPA standards and Chinese standards HJ1286 and HJ1013 for continuous monitoring of non-methane total hydrocarbons in stationary source emissions, ensuring stability and reliability.
Features a self-cleaning sample pre-treatment device that effectively handles fine particulate matter, water vapor, and other impurities, preventing damage to the analysis system.
Customizable sampling probes are available to meet installation requirements for different materials and specifications of exhaust pipes.
Utilizes GC-FID analysis, meeting international and domestic measurement standards, and offers method development for specific detection factors beyond conventional monitoring parameters.
Designed for various applications including standard and positive pressure explosion-proof configurations, ensuring stable and reliable operation in different safety-critical environments such as explosion-proof Zone 0.
Equipped with multiple data interfaces to meet the data acquisition needs of different users for monitoring data.

Applications

Continuous monitor non-methane total hydrocarbons in exhaust gases.

Detection Principle

FID (Flame Ionization Detection): When organic compounds are burned in a hydrogen flame, ions are produced in the flame. These ions are collected by electrodes with a DC voltage applied, and the current of these ions is measured using an electrometer, generating the corresponding gas chromatography for the substances.

Monitoring Factors

Single FID: THC
Catalytic Oxidation-FID: NMHC, THC
GC-FID: NMHC, THC, benzene series, or other customizable organic compounds

System Composition

Sample Conditioning Subsystem

The sample conditioning system handles the functions of sampling, backflushing, and calibration. The entire process is heated with no cold spots, preventing water vapor and sample condensation. The system's heating temperature is adjustable, and it integrates a high-temperature filter to prevent residual particulates from entering the analyzer, thus extend the service life of the instrument.

Online Analysis Subsystem

Utilizes GC-FID technique to conduct online analysis of various VOC samples. The instrument uses a high-precision quantitative loop for accurate sample quantification. After separation by the chromatographic column, samples are quantitatively analyzed by the FID. A hydrogen generator provides dry, pure hydrogen, while a zero gas generator supplies dry, pure zero-grade air for the chromatograph.

Temperature, Pressure, and Flow Monitoring Subsystem

Employs a pitot tube along with pressure and temperature sensors to measure flow rate, pressure, and temperature.

Oxygen and Humidity Monitoring Subsystem

Uses sensors to measure oxygen concentration and a microprocessor to calculate the humidity and oxygen concentration in the sample gas.

Data Acquisition and Processing Subsystem

Comprises a junction box, host computer, online monitoring software, enterprise DCS networking unit, and data transmission unit. The junction box powers all devices and receives their output signals. Data is transmitted via online monitoring software to environmental protection departments and can be networked with the user’s DCS system.

Specifications

Item	NHVOC-31
Operating Condition
Temp.	0ºC~40ºC
RH	0%～85%(no condensation)
Power Supply
Voltage	AC 220V±10%
Frequency	50Hz±1Hz
Power Consumption	Cabinet: 2KW(excl. Heat tracing pipe, compressor) Heat tracing pipe: 40W/m
Gaseous Pollutant
		NHVOC-31(G)	NHVOC-31(GB)
Measuring Range (customizable)	Methane	(0～50)mg/m³	(0～50)mg/m³
	THC	(0～250)mg/m³	(0～250)mg/m³
	NMHC	(0～200)mg/m³	(0～200)mg/m³
	Benzene	/	(0～50)mg/m³
	Methylbenzene	/	(0～50)mg/m³
	Xylene	/	(0～50)mg/m³
Data Collection and Process
IPC	1-way RS485 communication interface, 6-way RS232 communication interface
	Windows 7OS
Software	NHVOC-31 Control Software
Output	Standard version with 1-way RS232 interface. Customizable.
Dimension of Cabinet
W×D×H	600mm × 960mm × 1800mm

Download

2024-07-12

NHVOC-31 NMHC Continuous Monitoring System

Tel

+86 757 86718778
+86 757 86718629

Qr code

Follow the public account for more information

NHVOC-31 NMHC Continuous Monitoring System

Tel

+86 757 86718778+86 757 86718629

Qr code

Follow the public account for more information

+86 757 86718778
+86 757 86718629