WE440 Phosphate Analyzer

The Yokogawa WE440 Phosphate Analyzer is a continuous online analyzer used for early detection and precise phosphate monitoring in the boiler water supply. It is designed for optimized reagent consumption and features a compact size and simplified operation with on-demand mode for noncontinuous operational plants.

In steam production systems, phosphate is used for controlling the pH of boiler water to reduce corrosion problems in boiler systems as well as reducing buildup of deposits in the boiler and turbines. Too much phosphate can cause damage to steam and too little phosphate allows acidic conditions to develop, promoting corrosion. The WE440 Phosphate Analyzer helps regulate phosphate dosing to prevent these issues.

Why measure phosphate?

About OpreX

OpreX is the comprehensive brand for Yokogawa’s industrial automation (IA) and control business and stands for excellence in the related technology and solutions. It consists of categories and families under each category. This product belongs to the OpreX Analyzers family that is aligned under the OpreX Measurement category.



Advanced Flexibility - On-Demand Mode

Non-continuous plants have unique challenges in regard to measurement; peak power plants only run during certain times of the year. They will go dry for long periods of time, but always need to have water running through the system to prevent problems.

The phosphate analyzer auto-detects when no sample is in the chamber for five hours, and will prime the solutions and tubings so they do not dry out and crack. If six hours pass, then the analyzer goes into on-demand mode. If this analyzer is in place in a plant that shuts down, the on-demand mode is automatically triggered. When all of the reagent bottles are full, it can be left in this mode for 30 days.

Reduced Maintenance Time

WE440 Phosphate AnalyzerThe unique design of the tubing attachment allows for quick and simple replacement that is required only once a year. On-site personnel can swap them easily.

The peristaltic pump tubing requires replacement twice a year and also takes only a few minutes. The ease of maintenance keeps the unit running efficiently and keeps costs down.

Process Guard - Trustworthy Measurements

Lower temperatures can slow down a phosphate reaction, causing false or inaccurate readings. The phosphate analyzer contains a built-in temperature control that ensures that the phosphate is properly being measured.

Partition Design

There is a barrier between the electronics and wet sections of the enclosure. A solution cannot migrate into the electronics portion even if there is a pressure build up.

Expert Guide

The WE440 features a large, easy-to-read backlit display with multiple language options and simple menu navigation.

Why measure phosphate?

Phosphate is measured to regulate the pH of water used in steam raising boiler systems. Keeping the boiler water alkaline substantially reduces corrosion problems in boiler systems. Phosphorus reacts with scale-forming spices such as calcium and magnesium to produce soft sludge, reducing scaling problems in the boiler and turbine.

Too much phosphate can cause damaging carryover in steam, and too little phosphate can allow for acidic conditions to develop that encourage corrosion. Measuring phosphate ensures these issues do not occur.

Giving You More Insight




Yokogawa's Wet Chemistry analyzers are used for measurement of Sodium, Silica, Hydrazine, and Phosphate, and are suitable for keeping water quality at an optimal level for steam generation.

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