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1. Calculation of the discharge volume and discharge area of the gas cylinder rupture disc (refer to GB/T 33215-2016): 1.1 The safe discharge volume of the gas cylinder is calculated using the following formula: Ws = 0.177PM^0.5V (1). In this formula, the designed discharge pressure P (absolute pressure) is set at 30.1 MPa, M is 16 kg/kmol, and V represents the nominal water volume. By substituting the data into equation (1), the safe discharge amounts for the gas cylinders are obtained, as shown in Table 1: Table 1 Safe Discharge Amounts of Gas Cylinders V(L) 80 85 90 95 100 105 110 115 120 Ws(kg/h) 170 5 181 1 191 8 2025 2131 2238 2344 2451 2557 1.2 Calculation of the minimum discharge area of the rupture disc: Using the formula for the rated discharge capacity of the discharge device, Wr = 7.6×10^-2CKPA×(M/Z/T)^0.5 (2), where C is the gas-specific coefficient, the discharge coefficient K is taken as 0.6, the discharge pressure P (absolute pressure) is 30.1 MPa, A represents the minimum discharge area of the rupture disc, M is 16 kg/kmol, Z is the compression coefficient of the gas at absolute pressure P and absolute temperature T, and T is the absolute temperature of the medium at the discharge pressure. The formula for calculating the gas characteristic coefficient C is: C = 520 × (k × (2/(k+1))^((k+1)/(k-1)))^0.5 (3). Here, k is the adiabatic index of the gas; for natural gas, this value is 1.314. Substituting this value into equation (3) gives C = 348. The formula for calculating the gas compression coefficient Z is: Z = Z0 + Z’θ (4). With a discharge pressure of 30.1 MPa and a critical pressure of Pc = 4.6 MPa, the ratio of pressures Pr = P/Pc = 30.1/4.6 ≈ 7.0. The operating temperature of the discharge device is 110°C, so the absolute temperature T is T = 110 + 273 = 383 K. Using the absolute discharge temperature of 383 K and the critical temperature Tc = 190.56 K, the ratio of temperatures Tr = T/Tc = 383/190.56 ≈ 2.0. The compression coefficient Z0 for a simple gas (θ = 0) is 1.02 (as stated in Table A.1 of GB/T 33215-2016). The compression coefficient Z’ for a non-simple gas (θ ≠ 0) is 0.4 (as stated in Table A.2 of GB/T 33215-2016). The formula for calculating the compression coefficient correction factor θ is: θ = 3 × (lgPc + 1)/7 / ((Tc/Tb) – 1) – 1.0 (5). Substituting Pc = 4.6 MPa, Tc = 190.56 K, and the boiling point at atmospheric pressure Tb = 111 K into equation (5) gives θ ≈ -0.006. Using Z0 = 1.02, Z’ = 0.4, and θ = -0.006 in equation (4), we get Z ≈ 1.018. From equation (2) and the condition Wr ≥Ws, the minimum discharge area A of the rupture disc can be calculated as: A = Ws × 100/7.6/C/K/P/(M/ZT)^0.5 (6). Substituting C = 348, K = 0.6, P = 30.1 MPa, M = 16 kg/kmoL, Z = 1.018, T = 383 K, and V = 120 L, along with Ws = 2557 kg/h, gives A ≈ 26.4 mm². Using these values, Table 2 can be prepared: Table 2 Discharge Area V(L) 80 85 90 95 100 105 110 115 120 A(mm²) 17.6 18.7 19.8 20.9 22.0 23.1 24.2 25.3 26.4