Fertilizer and Methanol Turbines

With the growing size of methanol plants, the synthesis gas compressors which are at the hearts of these plants are also growing larger.

The photo at right shows a synthesis gas compressor train for a methanol plant in the 5,000 tons/day class and which was delivered in Saudi Arabia. It is a both shaft end drive steam turbine which provides a high-speed maximum output of (42,398 kW / 9,198 rpm) when driving an MCO synthesis gas compressor.

Many manufacturers of large-capacity steam turbines use double-flow types for the exhaust rotor casing. However MCO uses a single-flow type exhaust rotor casing that makes use of titanium alloy rotor blades in the low-pressure turbine, resulting in a more compact design.
The most important issue for high-speed large-output steam turbines is the reliability of the turbine rotor blades. In order to boost this reliability, MCO uses ISB blades (Integral Shrouded Blades) at all stages of its high-speed turbines.
When ISB blades are used, MCO performs performance analysis using flow CFD (Computational Fluid Dynamics) and strength analysis using three-dimensional FEM (Finite Element Method) analysis. Performance is verified at blade cascade tests. For strength, the most important issue is vibration strength, and the latest CFD analysis methods are used to quantify the vibration force acting on the turbine rotor blades. The results are combined with FEM analysis to produce analysis with a higher level of accuracy.
The suitability of these analysis results is verified by performing actual load tests with test turbines and measuring the vibration stress, providing us with even more reliable analysis methods.