Overview
Project name: chemical water treatment of Huainan Pingwei electric system
Treatment process: UF+ RO+ IX
Water yield (product): 280 m³/h at first-stage(RO)，150 m³/h at third-stage(RO)
               
Feedwater source: Huaihe River Water source after coagulation, clarification and filtration
Water quality: Contains organics, microorganism, colloidal particles and iron.
Time in operation: Since 2010
 

Plant Description
The water treatment plant receives water from the Huaihe River Water that has undergo process of coagulation with PAC clarifications DMF before it flows thru the UF , and an antiscalant is dosed before being fed to the RO system. The RO permeate moves into IX unit to produce water for  bioler.
                    
     

Plant Performance
Since the beginning of 2012, Ochemate Advanced Material Technologies has converted the two existing RO systems to use Ochemate CP101 as antiscalant. Based on the feed water analysis, 3mg/l of product is needed to prevent system scaling. The product is very effective, and the system is operating smoothly without any further scaling however, organic and biofouling are prevalent in the system due to high incoming organics and microorganism in the feed. A thorough studies on the types of fouling that was still affecting the system was carried out and a chemical cleaning programme was put in place as preventive measures to maintain a smooth operating RO system.

Fouling and cleaning 
Fouling system: The third-stage ultrafiltration device of chemical water.
Fouling status : deep fouling, the differential pressure reached 0.2MPa, and the flow rate decreased by more than 50%.
Foulant information: The system is polluted by organics, microorganism and colloidal particles from analysis.
Solution: Clean the system with Ochemate CLN772 and Ochemate CLN712, and then sterilize it with non-oxidizing biocide Ochemate TBC9527

Data before and after cleaning of ultrafiltration system:

Effect 

After cleaning and sterilization of the system, the water yield rate increase by 56% ~ 133%, the  differential pressure of ultrafiltration system decreased by 84%~87%, The system performance was obviously restored, the sterilization effect is good, and the growth of microorganisms has been effectively controlled. 

Fouling system: The first-stage RO system of chemical water.
Fouling status : In deep fouling, the first-stage differential pressure reached 0.6~0.7mpa, the second-stage differential pressure reached 0.2mpa,and the flow rate dropped below 60m3/h.
Foulant information: No scaling.The system is polluted by organics, microorganism and colloidal particles from analysis.
Solution: Clean the system with Ochemate CLN751 and Ochemate CLN711, and then sterilize it with non-oxidizing biocide Ochemate TBC9528
Data before and after cleaning of RO system:（The system has been in use for 10 years， and the Rejection rate is still around 85%.）