Overview

We can't solve problems by using the same kind of thinking we used when we created them .

Albert Einstein

A hybrid membrane plant encompasses several technologies and processes since a stand-alone membrane system cannotproduce high-purity quality product owing to physical and chemical constraints of synthetic membranes, and can foul prematurely. Some of the earliest hybrid membrane plants were designed for dairy plants ^[1]and for brackish water desalination. ^[2] Several hybrid membrane systems for various applications are discussed in Chapter 3. In this chapter, we describe the engineering process and operation of a typical hybrid membrane plant for producing high-purity water (HPW). Basically HPW encompasses a wide range of pure-grade water varying in quality: potable (drinking) water, deionised (DI) water for power plants, purified water for beverage and pharmaceuticals industry, and ultrapure water (UPW) for semiconductor manufacturing.

The optimal success of a well-designed plant depends on the ability to operate various systems achieving the highest possible output using minimum energy, and generatingaslittle waste as possible with maximum safety for employees and environment. Plant operation requires a diversity of problem-solving activities, which must occur in an information-rich environment. Current and historic plant data, and characteristics of equipment and information obtained from troubleshooting the failure spots must be available and integrated at points of decision.

The first step is a conceptual design - a process flow diagram (PFD) with mass and energy balances - followed by the design of each unit operation and culminating in well-defined operating conditions. ^[3]