The dosing device is a complete set of equipment with dosing, stirring, liquid transportation, automatic control and integration. It is widely used in raw water for power plants, boiler feed water, oil field surface gathering and dehydration treatment systems, and petrochemical various dosing systems. And wastewater treatment systems. Such as adding coagulant, phosphate, ammonia, lime water, water quality stabilizer (corrosion inhibitor), scale inhibitor, liquid insecticide, etc.
Second, the working structure principle
The dosing device is mainly composed of a solution tank, a stirring box (with agitator), a metering pump, a liquid level gauge, an electric control cabinet, a pipeline, a valve, a safety valve, a check valve, a pressure gauge, a filter, a base, an escalator, etc. (Can be configured according to the actual requirements of the user). The dosing device is prepared in the mixing box according to the required concentration of the medicine, and after mixing by the mixer, it is put into the solution box, and the metered pump (dosing pump) is used to deliver the prepared solution to the dosing point or the designated system. The complete dosing device has the characteristics of compact structure, safety and simplicity, and easy operation. The device can also carry out targeted design and configuration of necessary components according to the requirements of different technological processes of the user, to achieve suitable functions (such as automatic remote control), economical and practical.
Third, the process principle
The calcium and magnesium hardness in the boiler feed water will undergo chemical reactions under high temperature environment, or will crystallize to form insoluble scale, which is firmly attached to the heating surface of the boiler. This scale is a poor conductor of heat and will hinder heat conduction. Boiler tube explosion accidents, in addition, will also induce and exacerbate the chemical corrosion of the metal under the scale, the harm is quite serious.
Although the boiler condensate and feed water have undergone strict softening and desalination treatment, a small amount of calcium and magnesium hardness still enters the boiler water. If this hardness is not treated, scaling will also threaten the safe operation of the boiler. At present, Adding phosphate to furnace water is the most suitable treatment method. The reaction is as follows:
10Ca2 ++ 6PO43- + 2OH- → Ca 10 (OH) 2 (PO4) 6 (basic calcium phosphate)
Basic calcium phosphate is a kind of soft water slag, which is easy to be removed with the boiler sewage, and will not adhere to the boiler and become scale.
Fourth, the process overview
The device mainly includes four parts: a chemical solution system, a metering and dosing system, a safety system and a control system.
The solid phosphate is added into the dissolution tank, and then desalinated water or condensed water is added in proportion to stir and dissolve, and is added to the boiler drum by the metering and adding system. The dosing control can be manual or follow-up control based on the control signal output by the host system to automatically dosing.
Scope of application: high-pressure and higher parameters drum boiler water treatment
V. Precautions for Dosing Device Selection
1. When the user selects the dosing device, first determine the selection specifications (including the metering pump parameters, the volume of the stirring tank, the volume of the solution tank and the site conditions) according to the amount of solution to be added, and then determine the dosage according to the dosage. Determine the dosing method (generally "one open and one preparation" method)
2. Select the material (stainless steel, carbon steel, non-metallic material), metering pump model (diaphragm pump, plunger pump) of the components of the dosing device or the parameters (name, concentration, temperature) of the added drug to our company as required. , Density, viscosity, corrosiveness, etc.)
3. Other special requirements for dosing devices.
Six, ordering instructions
- 1. What kind of chemical solution is provided? Determine the material of the dosing device.
- 2. Dosing pump selected pressure and flow.
- 3. The solution tank is generally 1m3.
- 4, configured for several boxes and several pumps.
- 5. Are there any other special requirements?