01 Regeneration operation steps
1. Backwash stratification: open the mixed bed backwash drain valve and backwash inlet valve, start the self-use demineralized water pump, slowly open the backwash inlet manual valve, adjust the backwash flow, make the resin layer expand to the upper peephole 1/2 position, backwash until the drainage is clear and there is no broken resin and the yin and yang resin have been clearly layered, close the mixed bed backwash inlet valve and backwash drain valve, and stop the self-use desalination water pump.

2. Sedimentation: Open the mixed bed exhaust valve, let it stand for 5~10min, observe whether the peeping hole Yin and Yang resin delamination is obvious, if not, re-backwash and layer until the Yin and Yang resin are completely separated.

3. Pre-injection: open the mixed bed alkali inlet valve, acid inlet valve, intermediate drain valve, acid injector inlet valve, alkali injector inlet valve, start the self-use desalination water pump, adjust the opening of the inlet manual door of the injector, control the flow rate of 10~14t/h, and peep at the water surface of the hole during observation.
4. Acid and alkali intake: open the acid outlet valve of the acid metering box, the alkali outlet valve of the alkali metering box, the acid and alkali concentration meter of the mixed bed, adjust the manual door opening of the outlet of the acid and alkali metering box, and control the acid and alkali concentration of the outlet of the acid and alkali ejector to be 3%~4% and the alkali concentration 2%~3% for 50min.

5. Replacement: When the acid and alkali are finished, close the acid outlet valve of the acid metering box and the alkali outlet valve of the alkali metering box, and keep the flow rate of the ejector unchanged for replacement. During the replacement process, when the acid metering box inlet valve and the alkali metering box inlet valve are opened to replenish the acid and alkali to the required liquid level, the acid inlet valve of the acid metering box and the alkali inlet valve of the alkali metering box are closed. At the end of the replacement, stop the self-use desalination water pump, and close the mixed bed alkali inlet valve, acid inlet valve, intermediate drain valve, acid injector inlet valve, and alkali injector inlet valve for 50min.

6. In the process of acid and alkali intake, when the liquid level signal of the mixed bed acid metering box drops to a low level, open the acid inlet valve of the acid metering box, replenish acid to the acid metering box, close the acid inlet valve of the acid metering box when the liquid level signal of the mixed bed acid metering box rises to a high level, open the alkali metering box inlet valve when the liquid level signal of the mixed bed alkali metering box drops to a low level, replenish alkali to the alkali metering box, and close the alkali inlet valve of the alkali metering box when the liquid level signal of the mixed bed alkali metering box rises to a high level.
7. Drain water before mixing: open the upper drain valve and exhaust valve of the mixed bed, and close the upper drain valve when the liquid level drops to 200mm above the resin.

8. Grease mixing: open the compressed air valve of the mixed bed, mix the yin and yang resins, observe the uniform mixing of the yin and yang resins, and close the compressed air valve for 5~10min.
9. Washing, standby or running: After closing the compressed air valve, immediately open the mixed bed washing drainage valve and water inlet valve to prevent the resin from settling naturally, and close the washing drainage valve after 1min. Open the water inlet valve and exhaust valve of the mixed bed, when the water is discharged from the exhaust valve, open the washing drain valve and the instrument sampling valve, close the exhaust valve, and put the water conductivity meter and silicon meter at the outlet of the mixed bed. When the washing drainage DD≤0.15μs/cm, SiO2≤10μg/L, the regeneration is qualified, close the washing drain valve, open the mixed bed water outlet valve can be put into operation or close the mixed bed water inlet valve, the washing drainage valve and the instrument sampling valve, stop the bed for standby.

02 Regeneration precautions
1. When entering the acid and alkali, it is necessary to pay attention to monitoring the conductivity of the running bed to prevent acid and alkali from leaking and deteriorating the water quality.
2. The flow rate should not be too large at the beginning of the backwash layer, and the backwash flow rate should be increased after the resin is loosened.
3. During regeneration, we should observe whether the yin and yang resin delamination is obvious on the spot, and if it is not obvious, the backwash and layer should be re-washed until the yin and yang resin are completely separated.
4. After the regeneration is over, check that the pneumatic valves should be closed, especially the acid and alkali valves.
5. When closing the backwash water inlet adjustment door, pay attention to adjusting its opening to 0 to prevent damage to the middle row during the next operation. 6. Regeneration is operated in strict accordance with the regulations, concentrated acid and alkali are strongly corrosive, pay attention to personal safety and self-protection.