碩士 / 國立交通大學 / 環境工程所 / 89 / As the levels of drinking water regulation is getting more and more stringent,the update of treatment plants is becoming necessary.Membrane processes have been found wide applications in water treatment,and the nanofiltration is one of the most potential membrane process.Although it had been applied successfully in many plants,the development in Taiwan was just beginning.This study follow USEPA suggesting“ICR Manual for Bench- and Pilot-Scale Treatment Studies”,to test and evaluate the performances the performances and operation of NF by Pilot Plant Testing.
We have eight processes,and there are four purposes.The performance of the system and the types of foulants were decided by different pretreatment , including 5μm cartridge filter,granular activated carbon , acid, antiscalants, reductants.Besides, the necessity and selectivity of flush and chemical cleaning is studied ,and if the wastewater meets the standard in waterworks discharge is also evaluated.Finally,the raise of recovery,cleaning frequency,Langelier saturation index,SEM are involved in the fourth purpose.
The resuls shows turbidity and SDI are reduced by the 5μm cartridge filter
in 47 hours,and the capacity is 240 tons/m2.GAC can reduce total chlorine in 46 hours,but not always be effect.From process4-1 to 5,acid and foulants are added to prevent the formation of scaling,but the operation time only have 41.5,20,38 hours,that means the chemical pretreatment works bad.In process 6,Chlorine and Metal Oxides are prevented by adding Sodium metabisulfite,as a reductant and total operation time is 166 hours.It works.
In the system operation aspect,we have two results.Flush is necessary and we select the water after sand filtration as the source.The reagent for chemical cleaning is Phosphoric acid and Sodium hydroxide.
There are three kinds of wastewater,including concentrate,the wastewater after flush and afer chemical cleaning. The wastewater after chemical cleaning can not meet the standard of waterwoks wastewater discharge.But,if they are mixed,the mixed water can discharge under regulation.
The recovery can’t raised to 85%.Because the membrane flux is over the maximum recommended by Dow Chemical Co..Nanofiltration membrane has good performance in total hardness(77.04%) and TDS(74.25%).
| Identifer | oai:union.ndltd.org:TW/089NCTU0515009 |
| Date | January 2001 |
| Creators | Tsai-Rong Huang, 黃財榮 |
| Contributors | Jong-Nan Chen, 陳重男 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 273 |
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