principle

The hardness of calcium and magnesium in boiler feedwater can undergo chemical reactions or concentration crystallization in high temperature environments, forming insoluble scale that firmly adheres to the heating surface of the boiler. This scale is a poor conductor of heat and can hinder heat conduction. In severe cases, it may lead to boiler tube bursting accidents. In addition, it can also induce and exacerbate chemical corrosion of metals under the scale, which is quite harmful. Although the boiler condensate and feedwater have undergone strict softening and desalination treatment, there is still a small amount of calcium and magnesium hardness entering the boiler water. If this hardness is not treated, scaling will also pose a threat to the safe operation of the boiler. Currently, adding phosphate to the boiler water is the most suitable treatment method. The reaction is as follows:
10Ca2++6P04-+2OH - Ca, o (OH) 2 (PO4) 6 (basic calcium phosphate)
Alkaline calcium phosphate is a soft water residue that is easily discharged with boiler discharge and will not adhere to the boiler to form scale.

Process Overview

This device mainly includes four parts: drug solution preparation system, metering and dosing system, safety system, and control system.
Solid phosphate is added to the dissolution tank, and then mixed with desalinated water or condensed water in proportion to dissolve. It is added to the boiler drum through the metering system. The dosing control can be done manually or automatically based on the control signal output by the upper system.

scope of application
High pressure and higher parameter steam drum boiler water treatment.

Pipeline schematic diagram