The phosphate dosing device is an industrial equipment powered by a water pump and controlled by a metering device. It achieves quantitative, stable, and continuous dosing of chemicals such as phosphate through water flow, pressure, or water quality parameters. This device is primarily used in thermal equipment such as boiler drums in power plants, where it prevents scale formation and metal corrosion by adding phosphate, ensuring long-term stable operation of the equipment.
1. Process principle of phosphate dosing device
The calcium and magnesium hardness in boiler feedwater will undergo chemical reactions or condense and crystallize under high temperature conditions, forming insoluble scale that firmly adheres to the boiler heating surface. This scale is a poor conductor of heat, hindering heat transfer. In severe cases, it may lead to boiler tube bursting accidents. Additionally, it can induce and exacerbate chemical corrosion of the metal beneath the scale, posing serious hazards. Although boiler condensate and feedwater have undergone rigorous softening and desalination treatment, a small amount of calcium and magnesium hardness still enters the boiler water. If this hardness is not treated, it will also form scale, posing a threat to the safe operation of the boiler. Currently, adding phosphate to boiler water is the most suitable treatment method, with the following reaction:
10Ca2+ + 6PO43- + 2OH- = Ca10(OH)2(PO4)6 (basic calcium phosphate)
Basic calcium phosphate is a soft water slag that is easily removed with boiler blowdown and does not adhere to the boiler to form scale.

II. Overview of the process of phosphate dosing device
This device primarily comprises four components: the chemical solution preparation system, the metering and dosing system, the safety system, and the control system. Solid phosphate is introduced into the solution tank, followed by the addition of demineralized water or condensate water in proportion for stirring and dissolution. The solution is then delivered to the boiler drum via the metering and dosing system. The dosing control can be operated manually, or it can be automatically controlled based on the control signals output by the supervisory system for follow-up control and automatic dosing.

III. Scope of application of phosphate dosing device
High-pressure and higher parameter drum boiler water treatment. The dosing devices produced by our factory include systems for ammonia dosing in feedwater, hydrazine dosing, phosphate dosing in boiler water, ammonia dosing in condensate water, dosing for circulating water treatment, dosing for sewage treatment, etc. The dosing device mainly consists of four parts: control system, mixing system, dosing tank, common platform, and metering pump. Its unit combination form mainly depends on different user requirements, automation level (automatic or manual control), selection of dosing pump types, and flexibility in forming various different forms of units. It is installed on a base. This factory-made complete set of equipment features compact structure, complete configuration, rapid installation, simple operation, and convenient maintenance. The materials of the components of the unit combination device mainly include stainless steel, carbon steel, carbon steel with rubber lining, etc., which can be determined according to user needs.

IV. Introduction to the functional characteristics of the phosphate dosing device:
This device primarily consists of four parts: the chemical solution preparation system, the metering and dosing system, the safety system, and the control system.
Solid phosphate is added to the dissolving tank, and then mixed and dissolved with demineralized water or condensate water according to the proportion. It is then added to the boiler drum by the metering and dosing system. The dosing control can be performed manually, or it can be automatically controlled based on the control signal output by the supervisory system for follow-up control.

V. Ordering Instructions for Phosphate Dosing Device
1. This equipment is supplied as a complete set, with all equipment centrally installed on a steel base.
2. When placing an order, the user should specify the pressure rating and flow rate of the pump head.
3. This device is available in three types: stainless steel (1Cr18Ni9Ti), ordinary carbon steel, and PE. Users can choose any of them.
4. Specific requirements for dosing pumps.
5. According to the specific situation of each project, connect the demineralized water pipe or condensate pipe, sewer drainage pipe, and power supply and electrical switch for the boiler drum phosphate solution feeding pipe and metering pump according to the equipment foundation drawing requirements and equipment installation drawing.