Operating Precautions for Packaged Chemical Dosing Systems
2025-08-12
A packaged chemical dosing system is made up mainly of a solution tank, a mixing tank (with an agitator), a metering pump, a level gauge, an electrical control cabinet, piping, valves, a safety valve, a check valve, a pressure gauge, a strainer, a base frame, an access ladder, and similar components (the configuration can be tailored to the user's actual requirements). A flocculant dosing system prepares the chemical at the required concentration in the mixing tank; after the agitator mixes it uniformly, it is fed into the solution tank, and the metering pump (dosing pump) delivers the prepared solution to the dosing point or the designated system.
A packaged chemical dosing system is compact, safe, simple, and easy to operate. The system can also be specifically engineered to suit different process requirements, configured with the necessary components, and designed to provide suitable functionality (such as automatic remote control) while remaining economical and practical. The theoretical basis of a flocculant dosing system is the "coagulation" theory: a flocculant uses groups carrying a positive (or negative) charge to neutralize particles in the water that carry a negative (or positive) charge and are difficult to separate, lowering their electric potential so that they become unstable, and then using its agglomerating properties to bring these particles together so they can be separated out by physical or chemical means. Flocculants are used mainly in water supply and various wastewater treatment applications. After treatment, the wastewater can essentially meet discharge standards in terms of color, chromium content, and suspended solids content, allowing it to be discharged or used as reinjection water for artificial water-injection oil recovery.
Operating Precautions for Packaged Chemical Dosing Systems
1. The dosing metering pump motor is controlled by a variable-frequency drive (VFD). If the dosing metering pump fails to operate normally, the VFD may have faulted; in that case, switch over to the other pump (under normal conditions, one runs while one is on standby) and reset the fault according to the manual.
2. During use, the level gauge can become damp and have material adhere to it, and material on the surface of the level switch can then affect its performance. The dosing system should be inspected and wiped down regularly (once per shift is recommended).
3. The electrical components inside the control cabinet must be kept free of water. Keep the cabinet door tightly closed during normal use, and never wash the control cabinet with water; doing so will damage the electrical components.
4. Because the chemicals are highly corrosive, regularly inspect the various mechanical parts that come into contact with them and replace them promptly.
5. If the screen inside the feeder is damaged, replace it promptly, and avoid feeding large lumps of dry chemical into the screw feeder, which could damage the screw or the drive motor.
6. The diaphragm at the center of the head of each of the two pressure-type level gauges should be inspected and cleaned once a month.
7. Because the chemical is sticky, when conveying it pneumatically pay attention to whether the conveying line is clear, especially below the hopper and at the discharge outlet.
8. Under normal conditions, opening the end cap on the hopper inlet should produce a downward suction. If there is no suction or there is reverse airflow, the conveying line is blocked and should be inspected promptly. (It is recommended to open and inspect it after every 20 hours of dosing operation.)
9. There is a heater inside the hopper. Under normal conditions, after air has been supplied for a while the conveying line becomes slightly warm; if there is no change, the heater is damaged and should be inspected and replaced promptly.
10. The inlet valve and discharge valve are automatic ball valves. If water still flows in or chemical still flows out after they are closed, the inlet valve and discharge valve are damaged and should be inspected and replaced promptly.
11. The dosing metering pump must never run dry or in reverse. Before starting the pump, make sure the valves upstream and downstream of the metering pump are already open, and prime it with fluid in advance.
A packaged chemical dosing system is compact, safe, simple, and easy to operate. The system can also be specifically engineered to suit different process requirements, configured with the necessary components, and designed to provide suitable functionality (such as automatic remote control) while remaining economical and practical. The theoretical basis of a flocculant dosing system is the "coagulation" theory: a flocculant uses groups carrying a positive (or negative) charge to neutralize particles in the water that carry a negative (or positive) charge and are difficult to separate, lowering their electric potential so that they become unstable, and then using its agglomerating properties to bring these particles together so they can be separated out by physical or chemical means. Flocculants are used mainly in water supply and various wastewater treatment applications. After treatment, the wastewater can essentially meet discharge standards in terms of color, chromium content, and suspended solids content, allowing it to be discharged or used as reinjection water for artificial water-injection oil recovery.
Operating Precautions for Packaged Chemical Dosing Systems
1. The dosing metering pump motor is controlled by a variable-frequency drive (VFD). If the dosing metering pump fails to operate normally, the VFD may have faulted; in that case, switch over to the other pump (under normal conditions, one runs while one is on standby) and reset the fault according to the manual.
2. During use, the level gauge can become damp and have material adhere to it, and material on the surface of the level switch can then affect its performance. The dosing system should be inspected and wiped down regularly (once per shift is recommended).
3. The electrical components inside the control cabinet must be kept free of water. Keep the cabinet door tightly closed during normal use, and never wash the control cabinet with water; doing so will damage the electrical components.
4. Because the chemicals are highly corrosive, regularly inspect the various mechanical parts that come into contact with them and replace them promptly.
5. If the screen inside the feeder is damaged, replace it promptly, and avoid feeding large lumps of dry chemical into the screw feeder, which could damage the screw or the drive motor.
6. The diaphragm at the center of the head of each of the two pressure-type level gauges should be inspected and cleaned once a month.
7. Because the chemical is sticky, when conveying it pneumatically pay attention to whether the conveying line is clear, especially below the hopper and at the discharge outlet.
8. Under normal conditions, opening the end cap on the hopper inlet should produce a downward suction. If there is no suction or there is reverse airflow, the conveying line is blocked and should be inspected promptly. (It is recommended to open and inspect it after every 20 hours of dosing operation.)
9. There is a heater inside the hopper. Under normal conditions, after air has been supplied for a while the conveying line becomes slightly warm; if there is no change, the heater is damaged and should be inspected and replaced promptly.
10. The inlet valve and discharge valve are automatic ball valves. If water still flows in or chemical still flows out after they are closed, the inlet valve and discharge valve are damaged and should be inspected and replaced promptly.
11. The dosing metering pump must never run dry or in reverse. Before starting the pump, make sure the valves upstream and downstream of the metering pump are already open, and prime it with fluid in advance.