During the adiabatic throttling expansion of natural gas, due to the Joule-Thomson effect, a temperature drop usually occurs, with a pressure drop of 0.2 to 0.3 MPa and a temperature decrease of about 1 °C. Assuming that the natural gas pressure is adjusted from 4 MPa to 0.4 MPa, the temperature of the natural gas at the outlet of the pressure regulator will drop sharply by more than 12 ° C, especially in winter. When the temperature is below 10 ° C, the outlet temperature of the pressure regulator will drop below -2 ° C. . Since the conduit or valve port of the regulator pilot has a relatively small diameter, such as natural gas with moisture and impurities, it is highly likely that an ice block will form at the conduit or valve port of the regulator pilot, resulting in a pressure regulator. The pressure regulation function is out of order, and the high-pressure natural gas directly enters the pipeline downstream of the regulator, which directly affects the safety of the gas. In this regard, the normal operation of the regulator can be ensured by locally increasing the temperature of the natural gas at the inlet of the regulator.
Common methods for increasing the temperature of the natural gas at the inlet of the regulator or regulator pilot are: pipeline electric heating method, vortex pilot gas heater method, pilot heater method, heat exchanger method, etc., each heating method Each has its own advantages and disadvantages.
