Leakage flow carrying solid particles from a two-layer pipe system is widely encountered in the oil and gas industry. In this paper, the identification of particle-gas leakage flow from an inner pipe was developed, and leak point simulation equipment was designed. Typical statistical vibration time-behavior and time-frequency joint analyses were applied to characterize the particle leakage signal. Verification experiments were performed, and a sand particle identification frequency band from 10.2-10.95 kHz was discovered. Additionally, good agreement was found for sand particle (150 mu m) identification from the leakage gas flow at different leak points (diameters from 2 to 8 mm) under different release pressures (from 0.4 to 0.8 MPa). The sand vibration energy from one leak point increased with released pressure and leak size, while for two leak points, the sand vibration energy is more sensitive to the first point and decreases with the diameter of the second point. (C) 2019 Elsevier B.V. All rights reserved.