Overview
Dewpoint transmitter is suitable for continuous measurement of moisture in industrial process gas or liquids and convert it to dew point, or ppm(v).
Principle
MZD dew point analyzer uses a dual ceramic film capacitive sensor based on nanotechnology. The sensor is composed of two specially developed Low Temperature Cofired Ceramics (LTCC), the isolation layer and the moisture absorption layer. Its characteristic is that the response is very fast and very stable. The ceramic isolation layer is 10 nanometers thick and the DC impedance exceeds 2 megohms, forming an electrical isolation layer, which can effectively prevent the sensor from short-circuiting. The ultra-thin ceramic hygroscopic layer is only 24nm thick and sintered with the ceramic isolation layer. It has strong hygroscopicity and quickly responds to changes in the partial pressure of water vapor, and reacts to changes in its capacitance. The use of ceramic isolation layer allows us to minimize the thickness of the response layer, thereby obtaining a faster response speed than similar products.
Advantages
● Fast response
● Nano-based dual ceramic film capacitive sensor
● Wide pressure range (vacuum to 300 bar)
● Not sensitive to flow rate
● Built-in self-diagnostic system
● Robust mechanical construction
● Automatic calibration system, according to international standards (NPL)
Features and technical parameters
● Range: -100°C ~+20°C dew point or 0~1000ppm
● Accuracy: better than ± 2°C dew point
● Available output units: °C & °F dew point, ppm(v), ppb(v), g/m3, lb/MMSCF
● Temperature compensation
● Troubleshooting
● Long-term stability
● Fast response time
● IP66 / NEMA4X protection level
● Explosion-proof optional (intrinsically safe Ex ia)
Installation
● Installation is simple and can be installed directly on the pipe.
● Avoid installing at the bottom of the pipe bend where condensate is easy to deposit.
● Sampling points should be representative.
● Avoid contact with particles and oil droplets
● Use high-quality sampling tubes, especially for gases with a very low dew point, use low-hygroscopic materials such as stainless steel tubes or PTFE tubes.
Controller features
• Quick and convenient
The navigation menu contains 6 languages, which can be operated easily.
• Process safety
4.3" or 7" large size color LCD touch screen, convenient and safe touch operation and debugging
Large size screen with red flashing alarm, clearly visible from long distances and in dark areas
Alarm immediately, safe the process
• Alarm event record
Real-time data curve display
Record function for up to 6000 alarms
• Optional mass flow measurement and controller
• Expert calibration function
Multi-point calibration function up to 9 point
• Powerful self-diagnosis function
Built-in heartbeat monitoring function and watchdog
Monitor the status of controllers and sensors, and promptly remind customers to take necessary maintenance
High-standard hardware and software security and password protection
• Powerful control function
High(low) limit control function
Optional: Timer control(automatic cleaning) function
Optional: analog PID controller
Optional: PWM controller
• Flexible fieldbus communication functions for IOT4.0
Optional fieldbus MODBUS, HART, Foundation Fieldbus FF, PROFIBUS PA, PROFIBUS DP, etc.
Typical application
● Sulfur hexafluoride SF6 in circuit breaker
Sulfur hexafluoride is used as an insulating gas in circuit breakers. If the moisture in it is too high, it will cause an arc, which will cause the circuit breaker to operate and cut off the power transmission.
● Moisture in natural gas
The water in the high-pressure natural gas from the production wellhead may cause pipelines and valves to freeze. Excessive water content will also lead to the formation of liquid hydrocarbon hydrates, which will cause greater trouble. At the same time, the moisture in the gas will also reduce its calorific value, affecting product quality and price.
● Vacuum and gas recharge of oil-filled transformer
The moisture content is continuously monitored during the vacuuming and gas recharging of the oil-filled transformer. The water in the sealing gas dissolved in the oil will affect the dielectric properties of the oil.
● Instrument aire
It is used as a filling gas in the instrument, and the moisture in it may cause corrosion problems, and the change is too large during calibration, and at the same time affects the sensitivity of the instrument.
● Breathing
Excessive moisture in the breathing gas may cause the pressure regulator to freeze and block the orifice, resulting in interruption of the air supply.
● Hydrogen annealing furnace
If the hydrogen in the annealing furnace contains high moisture, it will cause the metal to oxidize and cause the surface finish of the product to be damaged.
● Ethylene gas in HDPE production
Excessive moisture content in the ethylene feed gas will reduce the catalyst activity and reduce the output of the ethylene reactor.
● Hydrogen-cooled generator
Hydrogen is used to cool large stationary generators due to its high specific heat capacity and low viscosity. In order to ensure its specific heat capacity and viscosity characteristics, hydrogen must be kept dry. The moisture in the environment is regarded as a factor that affects the above-mentioned characteristics.
● Injection
Excessive moisture in the air used to dry the plastic particles will adversely affect the quality of the final plastic product.
1. Reduce product strength.
2. The surface finish of the product is poor.
3. Make transparent plastic products turbid.
All these product defects will affect product output and increase production costs.
● Nuclear reactor
The gas-cooled reactor uses carbon dioxide gas to transfer heat from the nuclear reactor to the boiler to produce steam. The moisture content needs to be kept low to avoid corrosion, and moisture measurement can also be used for leak detection.
● Food packaging
For foods packaged in foil, if the trace gas in the foil is replaced with hydrogen with very low moisture content, the shelf life of the food will be prolonged.
Corrosive gas application note
MZD dew point analyzer can be used in some corrosive gases. The following table gives some guidelines in this regard. A certain amount of corrosive gas is allowed in the dry gas, but it cannot be used in some samples with high moisture content. It can be applied to all samples with water content if it is marked "no limit".
corrosive gases | Maximum allowable content ppm | Maximum allowable DewPoint temperature °C | Explosion limit in air (%LEL) | |
exhaust | no limit | no limit | ||
Freon | no limit | no limit | ||
natural gas | no limit | no limit | ||
Aromatic alcohols | no limit | no limit | ||
petroleum | no limit | no limit | ||
Br2 | Bromine gas | no limit | -12°C | |
CCl2F2 | Dichlorodifluoromethane | no limit | -12°C | |
CCl4 | Carbon tetrachloride | no limit | no limit | N/A |
CF4 | Carbon tetrafluoride | no limit | -12°C | |
Cl2 | Chlorine gas | Prohibited | ||
CH4 | Methane | no limit | no limit | 5,0-15,0% |
C2H2 | Acetylene | ^ | 0°C | |
C2H6 | Ethane | no limit | no limit | 3,0-12,5% |
C3H8 | Propane | no limit | no limit | 2,2-9,5% |
(CH2)2O | Ethylene oxide | Prohibited | ||
CH3OH | Methanol | 20 ppm | no limit | |
C4H11O | Ethylene glycol | no limit | no limit | |
C6H | Benzene | no limit | no limit | 1,4-7,1% |
C6H5CH3 | Toluene | no limit | no limit | 1,3-6,8% |
C6H5(CH3)2 | Xylene | no limit | no limit | 1,0-6,0% |
CO | Carbon monoxide | no limit | no limit | 12,5-76,2% |
CO2 | Carbon dioxide | no limit | no limit | N/A |
COCl2 | Carbonyl dichloride | no limit | -20°C | |
CS2 | Carbon disulfide | no limit | no limit | |
F2 | Fluorine | 10 ppm | -20°C | |
HBr | Hydrobromic acid | Prohibited | ||
HCl | Hydrochloric acid | Prohibited | ||
HCOOH | Formic acid | Prohibited | ||
HF | Hydrofluoric acid | 500 ppm | -20°C | |
Hg | Mercury | Prohibited | ||
HNO3 | Nitric acid | 10 ppm | ^ | |
HClO4 | Perchloric Acid | Prohibited | ||
HOCH2CH2OH | Ethylene glycol | no limit | no limit | |
H2O2 | Hydrogen peroxide | Prohibited | ||
H2S | Hydrogen sulfide | no limit | no limit | 4,3-45,5% |
H2SO4 | Sulfuric acid | 10 ppm | -20°C | |
NaOH | Sodium hydroxide | Prohibited | ||
NH3 | Ammonia | 1400 ppm | -10°C | 16,0-25,0% |
NO2 | Nitrogen Dioxide | no limit | ^ | |
N2O | Nitrous oxide | no limit | ^ | |
O2 | Oxygen | no limit | no limit | |
O3 | Ozone | Prohibited | ||
SO2 | Sulfur dioxide | no limit | no limit | N/A |
SF6 | Sulfur hexafluoride | no limit | no limit | |
SO3 | Sulphur trioxide | no limit | -20°C |
*The data above might change with the deepening of research and experiment of the MZD laboratory and user experience.
Product datasheet: DewPoint Transmitter/Analyzer SMART-DP , if you need more information, please contact us at info@mzdd.de.