Daily Operation Standard for Circulating Water Treatment Chemical Addition

Daily Work Details for Water Treatment Chemical Addition Personnel

1. Principles of Chemical Addition

(1) Add chemicals accurately, on time, and in the correct amount;

(2) When using intermittent blowdown, chemicals should be added after blowdown;

(3) Before each chemical preparation, the preparation tank must be thoroughly rinsed before adding the chemicals. After adding the chemicals, rinse the preparation tank 2-3 times;

(4) If two bactericides and algicides are used, they should be added alternately, with even time intervals between additions;

(5) Do not add scale inhibitors and corrosion inhibitors on the day that bactericides and algicides are added;

(6) Keep detailed records of daily chemical addition and blowdown/replacement situations.

2. Chemical Addition Methods

Depending on the system status and chemical properties, bactericides and algicides can be added directly to the collection pool. The method for adding scale inhibitors and corrosion inhibitors is as follows: A chemical preparation tank is set up next to the circulating cooling water collection pool. The top of the preparation tank has a water supply pipe, and the bottom has a drain. The chemicals are added to the preparation tank, diluted with supplementary water, and then continuously and uniformly added to the collection pool using a metering pump.

3. Chemical Addition Locations

When adding chemicals to the collection pool, avoid areas near the drain to prevent chemicals from being directly discharged without entering the circulating water system; allow sufficient mixing time for the chemicals in the pool to ensure uniform mixing; avoid adding chemicals near the inlet of any pump, as this can cause uneven chemical concentration distribution.

4. Chemical Addition Methods

(1) Method for adding scale inhibitors and corrosion inhibitors: Add the required amount of chemicals to a clean preparation tank. While continuously stirring, add supplementary water to dilute the chemicals by 3-5 times (dilution is to balance the chemical addition time; dilution may not be necessary depending on the situation). After stirring evenly, turn on the chemical pump and adjust the chemical valve to continuously and uniformly add the chemicals to the collection pool, ensuring completion within 20-24 hours.

(2) Method for adding bactericides and algicides: Use an intermittent shock addition method. Add the required amount of chemicals directly to the collection pool to maintain a certain chemical concentration in the circulating water for a period of time, thereby achieving the most effective killing and stripping effect.

5. Precautions

(1) Neatly stack water treatment chemicals by brand in the warehouse to avoid confusion and misuse.

(2) Refer to the water quality test results (concentration factor, turbidity, total phosphorus), circulating water control indicators, and chemical addition table, and perform blowdown, replacement, or chemical addition operations as required.

(3) When operating, personnel should wear protective equipment to avoid direct contact between chemicals and skin and eyes. If chemicals accidentally come into contact with the skin, immediately rinse thoroughly with plenty of water.

(4) The method of adding water treatment chemicals must be strictly followed according to relevant requirements, and safety production work must be done well.

Circulating Cooling Water Operation and Control

1. Based on the daily water quality analysis results, control the blowdown water volume, supplementary water volume, and chemical addition volume as necessary to achieve the required indicators.

2. When turbidity > 20 mg/L, increase the blowdown water volume, increase the side filtration flow rate, and supplement clean water until the circulating water turbidity < 20 mg/L.

3. Based on the system status, try to increase the concentration factor to save water and chemicals. If the concentration factor > 4 times, increase the blowdown water volume, supplement clean water, and replace until the concentration factor < 4 times.

4. Control of total phosphorus in circulating cooling water. Based on the properties of the scale inhibitor and corrosion inhibitor, the total phosphorus in the circulating cooling water should be controlled within the range of 6-10 mg/L.

(1) If the blowdown water volume is large, causing the total phosphorus to be too low, appropriately add scale inhibitors and corrosion inhibitors to reach the required total phosphorus level, and adjust the blowdown water volume.

(2) If the circulating water system is normally blowdown, but the total phosphorus is low, it is necessary to analyze and check whether the chemicals have expired or the deviation is too large. If the above reasons are ruled out, increase the chemical addition amount to meet the total phosphorus target.

(3) If the total phosphorus in the circulating water is greater than 10 mg/L, do not add scale inhibitors and corrosion inhibitors.

5. When abnormal phenomena and problems are found in the operation of the circulating cooling water system and water treatment work, they should be reported and handled to the relevant personnel in a timely manner, and records should be kept.