METHOD OF UTILIZATION OF POTENTIAL ENERGY OF GAS TRANSPORTED VIA MAIN PIPE LINE ACCOMPANIED BY REDUCING AT GAS DISTRIBUTING STATIONS AND DEVICE FOR REALIZATION OF THIS METHOD

摘要

FIELD: power mechanical engineering; gas transportation systems; combined generation of electric power and production of liquefied gas. SUBSTANCE: proposed method consists in separation of compressed gas into flows: one flow is equal to 0.7 - 1.0 of total flow (depending on season); this flow is directed to vortex power dividers where potential energy of compressed gas flow is used at ratio of π = 2.3-2.5 and is divided into cold and hot flows at flow rate ratio of Q_c/Q_h= 1.2-2.3, hot flow is cooled in heat exchangers located in succession in way of gas flow, after which it is fed to condensate receivers and liquid fractions of heavy hydrocarbons are separated and then it is mixed with cold flow from vortex tube and potential energy of mixed flow of gas dehumidified in gas-expansion machine is used; gas is heated in heat exchangers located between gas-expansion machines and is mixed with second flow which is equal to 0-0.3 of total rate; after preheating, it ensures temperature of no less than T ≥ 273K, after using the potential energy of gas in parallel gas-expansion machines; then, it is cooled in outlet heat exchanger and is fed to condensate receiver where liquid fractions of heavy hydrocarbons are separated. Device proposed for realization of this method has dispensing branch pipe 2 connected to high-pressure gas source; one tap of this branch pipe is connected with inlet of first vortex tube 6 or "n" vortex tube 7 via cut-off valves 3 and 4 and pressure stabilizer 5; other tap of this branch is connected with low-pressure gas dispensing manifold 19 via compensating pipe line 8 including cut-off valve 9, inlet heat exchanger 10 cut-off valve 11, compensating gas-expansion machines 12, 13 and 14 provided with electric generators and clutches 15, outlet heat exchanger 16 and condensate receiver 17 and outlet mixer. High-temperature outlet of vortex tubes 6 and 7 are connected with one inlet of mixer 29 by flow pipe line including inlet heat exchanger 10, first intermediate heat exchanger 20, second intermediate heat exchanger 21 and "n" intermediate heat exchanger 22, condensate receivers 23, 24 and 25, cut-off valves 26 and 27 and return manifold 28; other inlet of mixer 29 is connected with low-temperature outlet of vortex tubes 6 and 7. Outlet of mixer 29 is connected with outlet mixer 18 by means of mixed flow pipe line including cut-off valve 30, first, second and "n" additional gas-expansion machines 31, 32 and 33 and closing gas-expansion machine 34 with clutches and mechanical energy consumers 35, 36, 37 and 38, heat exchangers 20, 21 and 22, cut-off valves 30, 40, and 41 and outlet heat exchanger 16 with outlet mixer 18; all these components are located in succession. Discharge manifold 51 is connected to mixed flow pipe line after mixer 29, intermediate heat exchangers 20, 21 and 22 and gas-expansion machines 31, 32, 33 and 34 via cut-off valves 42, 43, 44, 45, 46, 47, 48, 49 and 50. Hot flow pipe line is connected with inlet of mixer 29 through cut-off valves 52 and 53 fitted after each condensate receivers 23 and 24 and return manifold 28. EFFECT: optimal utilization of energy of entire spectrum of pressure drops and flow rates of gas from main pipe line. 20 cl, 4 dwg