First, the equipment overview
In the chemical water treatment system, in order to increase the pH of the make-up water and prevent metal corrosion of the water system, it is necessary to add ammonia, add hydrazine, and add phosphate to treat.
The dosing device produced by the company has three main categories: raw water treatment and dosing device, boiler feed water and furnace dosing device, wastewater and gray water dosing device. The method of dosing is based on the requirements of each power plant for the degree of dosing automation. The local manual and local automatic mode or computer automatic dosing method can be used to make the water quality meet the standard to ensure the safe and economic operation of the power plant.
Second, equipment and system description
(1) Design scope: each set of phosphate dosing device.
(1) Pipeline valves: all made of stainless steel.
(2) Solution tank: 1 cubic meter stainless steel medicine box. The dosing device is a two-box three-pump method.
(3) Metering pump: The hydraulic diaphragm metering pump produced by the tide pump industry. (see instructions for details)
(4) All equipment is installed on the steel frame to make installation easy and easy to maintain.
(5) Electrical control: equipped with independent electrical control cabinet, the cabinet has: manual switch motor for metering pump motor, metering pump motor for manual operation, operation button, alarm light, etc.
(6) Metering pump motor operation mode: manual button - relay - pump motor
(7) The phosphate dosing device controls the motor by manual operation and controls the dosing amount.
Third, the internal circuit is detailed in the electrical schematic diagram, each electrical wiring diagram.
Fourth, the operating procedures:
(1) Preparation before starting: (The various dosing devices are basically the same, it is important to note that the high pressure range of the phosphate dosing station should be strictly in accordance with the safety regulations)
Note: The metering pump and the agitator motor are turned clockwise (the motor casing is marked with a turn signal).
1. Manually adding water: adding and removing salt water to the specified position of the solution tank
2. Manual dispensing: Add various drugs to the box and reach the specified concentration (can be determined manually).
3. Inspection of all parts of the pump
(1) Whether the oil reaches the standard line (the body of the pump is inorganic oil before leaving the factory)
(2) Check if the relevant low pressure valve is opened or closed as required to avoid opening the pump.
(3) Check if the relevant high pressure valve is opened or closed as required to avoid suffocating the pump.
(4) If any liquid is found to be backflushed into the tank, the diaphragm of the pump has broken and must be replaced immediately.
(5) Oil must be replaced every six months (No. 46 anti-wear hydraulic oil, use of unclean oil is prohibited).
(6) The Y-type filter is cleaned every three months. After cleaning, there is air in the low-pressure pipeline. At this time, the pump should be vented. (The pump should be opened manually. When venting, the bleed screw should be released. A little, as long as there is water out), wait until the water flow is intermittently ejected from the venting hole, indicating that the pressure has entered the high pressure zone.
(7) Adjust the pump output:
1 Small-scale adjustment: According to the scale on the adjustment handle 10%-100%weiwei can be rotated, generally should take 30%-90% for the value.
2 Large-scale adjustment: Next to the oil hole, turn the small cover and adjust it with the inner hexagon weiwei. Clockwise is large and counterclockwise is small.
(2) Start:
1. Manual control: This device is a manual dosing device.
(1) Close the main power switch, close the shunt power switch, and close the control power switch. At this time, the green light is on.
(2) Press the button switch to the "manual" position.
(3) If there is no abnormality in the dosing pump and other mechanical parts, press the start button of the corresponding pump. At this time, the green light is off, the red light is on, and the dosing pump enters normal operation. Otherwise, press the stop button of the corresponding pump. At this time, the green light is on, the red light is off, and the dosing pump stops running.
(4) Similarly, the mixer motor can be started and stopped (Note: the mixer is not in the automatic range)
(5) Pay attention to whether the indication of the pressure gauge is normal. Sometimes, due to the air mixed in the low pressure end, bubbles are formed at the pump outlet gradually, so that the diaphragm movement cannot form the pressure. At this time, the air can be removed by using the bleeder screw and then tightened.
(6) During the first half hour of running zui, pay attention to the temperature rise of the motor, the indication of the pressure gauge and the working conditions of the various components.
(7) When operating normally, a clear impact sound should be heard in the inlet and outlet of the pump.
2. Automatic control: Automatic control can be entered when the manual status is all normal.
(This device does not have automatic control)
1) Close the automatic dosing power switch (recommended: disconnect the manual dosing shunt switch).
2) Turn the transfer switch to the "AUTO" position.
3) At this time, as long as the PLC has a signal output, the pump motor will rotate at a certain frequency.
4) If there is any abnormality, you can check it according to the circuit maintenance.
5) Please refer to the operation of the electrical cabinet
5. Drawings: Be familiar with the drawings before operation.
Sixth, equipment maintenance
(1) Pipeline maintenance reference system diagram, equipment installation diagram.
(2) See the instructions for the repair of the dosing pump.
(3) Instrument maintenance See the instrument manual.
(4) Refer to the electrical schematic diagram and electrical wiring diagram for electrical maintenance.
Points for electrical maintenance:
1. The maintenance personnel should be familiar with the electrical schematic diagram. On this basis, the electrical wiring diagram can be viewed correspondingly. First, a reasonable repair idea is formed, and then the fault is reasonably checked and gradually approached, and the cause of the fault is found and solved.
2. It is necessary to distinguish the direction of the main circuit and the control circuit, strictly implement the correct method of adjusting the control circuit first, and then adjusting the positive main circuit. On this basis, it is also necessary to remember to first adjust the "manual" circuit and then adjust the "automatic" "The general steps of the circuit to avoid overloading with the load, resulting in the consequences of expanding the fault surface.
