Measurement of hydrogen and carbon monoxide in industrial trade?

In industrial trade settlements, high-pressure hydrogen and carbon monoxide are typically measured using thermal mass flow meters or turbine flow meters. Standard conditions volume is usually used for settlement (that is, the volume of a gas at a standard temperature and pressure). The models of the accompanying flow meters include Shanghai Tongxin FC6000; the parameters that need to be set include the type of gas, pressure, temperature, flow rate, etc. When purchasing a flow meter, parameters such as the medium type, maximum and minimum flow ranges, operating pressure, fluid temperature, and pipe size need to be provided. .

Flow meter type: Hydrogen flow meter – Due to the flammable and explosive nature of hydrogen, flow meters with explosion-proof features are usually chosen. For example, the hydrogen flow meter mentioned in Reference Article 1 has a fully metal construction, making it suitable for use in high-temperature, high-pressure, and highly corrosive environments, as well as in hazardous areas where flammability and explosiveness are a concern. Carbon monoxide flow meter: Although there are no specific requirements regarding the type of flow meter for carbon monoxide, it is still necessary to take into account factors such as the pressure and temperature of the medium in order to select a suitable flow meter. Settlement method: In industrial trade settlements, the volume under standard conditions is usually used as the unit of measurement. This is because the standard condition volume eliminates the influence of pressure and temperature on gas volume, allowing gas flow rates under different conditions to be compared and calculated. Manufacturer and model of the flow meter: The Shanghai Tongxin FC6000 you mentioned is a model of flow meter, but to determine whether it is suitable for measuring high-pressure hydrogen and carbon monoxide, it is necessary to consult the technical specifications and user manual for that model. On the manufacturer side, Jiangsu Aoke Instrument Co., Ltd. is also a company that produces flow accumulators; its products may include flowmeters and accumulators suitable for various media and conditions. Settings for FC6000: If it is chosen to use the Shanghai Tongxin FC6000 flow meter, the settings that typically need to be configured include: flow measurement unit (such as volume at standard conditions), medium type (hydrogen or carbon monoxide), flow range, pressure and temperature compensation (if supported by the meter), communication settings (if communication with other systems is required), and other advanced function settings (such as power failure memory, password protection, etc.). Parameters required when purchasing the flow meter include: medium type (hydrogen or carbon monoxide), operating pressure, operating temperature, flow range, pipe diameter, connection method (such as flange, thread, etc.), and any other special requirements (such as explosion protection, corrosion resistance, etc.)

Gas metering generally uses flow rates under standard conditions as the unit of measurement. The method you employ involves using external temperature and pressure compensation to measure flow rate, pressure, and temperature; thereafter, an integrator is used to convert the flow rate under actual operating conditions into a value corresponding to standard conditions. As mentioned in the answer on the first floor, hydrogen requires explosion-proof measures, so it is necessary to take into account the explosion-proof requirements for the three sensors used to measure flow rate, pressure, and temperature. Additionally, it is important to know the following parameters: pipe material requirements, pipe diameter, connection requirements, flow rate range, operating pressure, operating temperature, and signal output. As for how to set it up, that’s something the supplier will take care of for you.

Received, thank you! I’d like to ask further: the company uses steam from another company; the pipelines are quite long, and at that company the pressure is likely around 0.5 Mpa with a temperature of 180 degrees Celsius. Upon reaching my company, the pressure drops to 0.45 Mpa and the temperature is 175 degrees Celsius. Which pressure and temperature values should be used as the basis for selecting a steam flow meter in this case? How to set the parameter options for “Design condition temperature,” “Design condition pressure,” “Standard condition temperature,” and “Standard condition pressure” in the Shanghai Tongxin FC6000 flow totalizer? Why does changing the value of the \"design condition pressure\" affect the magnitude of the instantaneous flow rate?

Design condition temperature and design condition pressure: These two parameters are typically used to describe the standard operating environment taken into account when designing a flowmeter. In the case of your company, although the actual operating temperature and pressure differ from the design conditions, the parameters for those design conditions are typically set to the standard values at which the flow meter is calibrated at the time of manufacture, such as standard atmospheric pressure (0.101325 Mpa) and a certain standard temperature (such as 20 degrees Celsius). Therefore, the settings for the design condition temperature and design condition pressure should be consistent with the standard values used for calibrating the flowmeter at the time of manufacture. Standard state temperature and standard state pressure: These two parameters are used to convert the actually measured flow rates into flow rates under standard conditions, so as to enable comparison and calculations. In the FC6000 flow integrator, the settings for standard temperature and pressure can be adjusted as needed, but it is generally recommended to follow international standards or industry norms. For steam flow measurement, the temperature under standard conditions is generally set at 0 degrees Celsius, and the pressure under standard conditions is generally set at 101.325 kPa (i.e., 1 atmosphere). Effect of changing the “design condition pressure” value on instantaneous flow rate: When the “design condition pressure” value is changed, what is actually being altered is the sensor’s sensitivity to pressure changes. Since the density and flow rate of steam are closely related to pressure, changing the pressure value at the design condition directly affects the flow meter’s calculation of the instantaneous flow rate. Specifically, if the design pressure value is increased, the flow meter will be more sensitive to pressure changes, which may result in an increase in the measured instantaneous flow value at the same actual flow rate ； Conversely, if the design condition pressure value is reduced, it may lead to a decrease in the measured instantaneous flow rate. Therefore, when adjusting these parameters, it is necessary to ensure that they match the actual working environment in order to guarantee the accuracy of the measurements.

You have completed the trade settlement with the steam supplier. What you described earlier is considered normal pipe loss, and it is usual to negotiate who will bear this cost. The parameters of design temperature and design pressure are generally set in flow meters of the type that use differential pressure; in other words, these values are determined based on the design temperature and pressure of the throttling device. Your flow meter also needs to have these same design temperature and pressure settings in order to yield accurate results.

For trade settlement, flow meters that meet the accuracy requirements and have passed calibration are sufficient. We use various Venturi types and EJA differential pressure transmitters; BOSIDA’s integrators are provided for reference. Additionally, steam metering is of course compensated using the temperature and pressure at the customer’s location, but generally, pipe losses or fixed fees are added to the cost. See how to sign the contract.