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Rossiter & Associates
Pinch Analysis Summary

Pinch analysis is...

A group of systematic techniques, based on thermodynamic principles, for

Analyzing heat flows
Establishing targets for energy use
Identifying inefficiencies in processes
Defining process improvements
Debottlenecking
Optimizing utility consumption

Pinch analysis is not...

The answer to every design problem
A substitute to good basic engineering

The techniques are applicable to any process that includes heating and cooling, e.g., oil refining, petrochemicals, organic and inorganic chemicals, pharmaceuticals, mineral processing, etc. The key concepts are illustrated in hot and cold composite curves, which represent the overall heat release and heat demand profiles of a process as a function of temperature. The region of closest approach – the pinch – is a key design parameter:

We can use pinch analysis to...

Establish targets for optimum energy consumption
Design heat integration systems for optimum heat recovery
Optimize utility systems (steam, cogeneration, refrigeration, furnaces, etc.)
Identify opportunities for heat pumps

Applications include:

New plant design: Generate options to...

Improve energy efficiency
Optimize utility system design
Reduce emissions (especially CO2, SOx and NOx)
Reduce capital cost.

Existing facilities: Analyze design and operating data to develop options to...

Improve energy efficiency
Debottleneck process units
Reduce emissions (especially CO2, SOx and NOx)

Advantages:

Pinch analysis has several advantages over "conventional" design approaches:

A systematic procedure. It guarantees an optimum solution without relying on luck or inspired guesses by the design engineer.
A common denominator methodology. Based on fundamental thermodynamics, pinch analysis applies to all processes and technologies, continuous and batch, new and retrofit.
Proven energy savings. Reductions of 15% or more in energy cost are typical, even where processes have already been optimized by "conventional" methods.
Automatic pollution prevention. Reduced CO2, SOx and NOx emissions are the natural consequence of better energy efficiency.
Lower cost debottlenecking. Pinch analysis shows us how to make better use of existing equipment and systems, and thus minimizes new equipment requirements in capacity upgrades.

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