Employment of a centrifugal turbine for the utilization of the natural gas energy within the process of pressure reduction

There is no doubt that turboexpander generation technology has considerable benefits such as reduction of CO2 emission and maintaining autonomous power supply for gas letdown stations and some technological processes. In spite of the abovementioned advantages of this technology its further development faces challenges due to: 1. long payback period of plants with conventional turbines; 2. significant annual fluctuations of gas inlet parameters; 3. high demands of conventional turbines for working fluid cleanliness. In current study the bladeless centrifugal reaction turbine was considered in order to struggle with abovementioned constraints. The investigated turbine is a variation of so-called Segner wheel known for centuries. Its efficiency is lower comparing with the conventional rotary machines, but remains beneficial within the specific conditions of turboexpander application. A comparison of the proposed turbine and axial transonic one was provided within a wide range of pressure ratios as typical operating conditions. The advantages of the investigated centrifugal turbine such as ability to generate comparable power as conventional ones while having lower cost and higher mud and erosion resistance has been highlighted.