SECTION III. PRINCIPLES OF OPERATION - TM-55-1905-223-24-70023

TM 55-1905-223-24-7

Table 1-1. Characteristics and Data - CONT

Characteristic

Reference Data

RO Element

Water Flow

400 gallons per day

Minimum Salt Rejection

98.6%

Maximum Operating Temp erature

1220F (500C)

1-10. Safety, Care, and Handling. Safety precautions must be observed at all times while performing maintenance.

General WARNINGS and first-aid data appear in the front of this manual. Review all safety information before starting any

task.* Carefully read through an entire maintenance procedure before performing any maintenance function. Make sure

the task can be done safely. All WARNINGS, CAUTIONS, and NOTES are of great importance to your safety and the

safety of the equipment.

SECTION III. PRINCIPLES OF OPERATION

Overview of Watermaker Operation. There are four main functions of the watermaker. Feedwater

decontamination takes contaminated elements out of the water. Pressurization is an essential function of

the system. Product water that has gone through the essential RO membrane is salinity tested and piped

to freshwater storage tanks. The fourth function is monitoring, which is a continuous check on water

quality.

1-11. Feedwater Decontamination. Water decontamination includes straining, filtering, and air/oil separation.

Feedwater entering the watermaker passes first through the 80-per-inch mesh of the raw water strainer and finally through

the polypropylene filter cartridges of the micron prefilters where contamination above 5 microns is removed. In between

the strainer and the filters, an air/oil separator removes high percentages of air and oil contamination.

1-12. System Pressurization. A positive displacement high pressure low volume pump draws water out of the micron

prefilters and discharges it at 800 psi into the RO elements. The 800 psi regulated operating pressure is essential to the

efficiency of permeation of the RO elements. A pressure regulating valve automatically maintains this pressure.

1-13. RO Diffusion/Permeation. The RO element is the heart of the watermaker and the internal thin film RO

membrane is the key component within each element. The application of high pressure feedwater to one side of the RO

membrane forces pure water through the molecular pores of the membrane but keeps out dissolved solids.

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