Water Supply, Condensate, Ammonia Dosing System

Process Principle

Free CO₂ in water can make the water acidic, as shown in the following reaction: CO₂ + H₂O → H⁺ + HCO₃. Thus, the H⁺ in the water can cause hydrogen depolarization in metals such as carbon steel.

Chemical corrosion causes damage to ferrous components, and the reaction is as follows: H⁺ + 2e → H₂  Fe→Fe²++2e

Especially in chemically demineralized water with high temperatures and no buffering capacity, free CO₂ greatly promotes steel corrosion, so this electrochemical reaction must be suppressed. Adding ammonia to the water to raise the pH value can effectively inhibit the dissociation of H⁺, thereby controlling metal corrosion.

Process Overview

This device mainly consists of five parts: a drug liquid metering system, a dissolution and preparation system, a metering and dosing system, a safety system, and a control system.

Ammonia water is drawn into the metering system via a water ejector, then added proportionally to the dissolution and mixing system to form a homogeneous mixture with demineralized water or condensate. Finally, it is added to the boiler condensate or feedwater via a metering and dosing system. Dosing control can be manual or automatic, based on control signals from a higher-level system.

Application areas

Condensate and feedwater treatment for medium-pressure and above boilers

Data parameters