EDR Vs ​RO for Water Treatment

What is the ​best water ​treatment ​method for ​water with the ​following given  ​specifications ​to use water ​for Drinking ​and Cooling ​purposes?  ​

We get our ​water from two ​brackish water ​surface wells.​  ​

• Water from ​well 1 will be ​used for ​drinking and ​
• Water from ​well 2 for ​plant cooling ​purposes (​closed cooling ​loop). ​

Which method ​will give ​better results -​ Electrodialysis ​Reversal or ​Reverse Osmosis ​and why? ​

Taxonomy

• Treatment
• Produced Water Treatment
• Industrial Wastewater Treatment
• RO Systems
• Drinking Water Treatment
• Water Treatment & Control
• Industrial Water Treatment
• Purification
• Reverse Osmosis
• Industrial Water Treatment
• Water Quality
• Brackish Water
• Electrodialysis
• Reverse Osmosis
• RO & MSF Fouling
• Water Supply
• Drinking Water
• Water Quality Monitoring
• Water Treatment & Control
• Cooling Systems
• Water Purification
• Total Dissolved Solids (TDS)

20 Answers

1. TSS and Turbidity does not match, TSS probably will be much lower. Measurement of TSS for low levels is very difficult.

   SDI15 should give a better understanding of the quality, but probably should be lower than 1.

   As other people mentioned, EDR will give you a higher recovery (85-90 %) but every stage will reduce the TDS 50% average. It's very easy to calculate the number of stages you need knowing the quality you want to achieve. Two stages is ideal, three stages is the higher economical number. Advantages: No biofouling, even during standby time,Chlorine gas production (You save a lot of money in hypo to sterilize the product water) No membrane replacement in many years. Membranes are chlorine resistant. No sand filters for this water, only cartridge filters as pre treatment. 

   RO is also a good option. Perhaps you do not need sand filters as well. It will depend on the amount of colloids. A measurement of SDI15 will give you the answer. 

   CAPEX and OPEX data is needed to take a decision

2. cheraghi@mapnamd2.com

3.  I have a project near this analysis ,the wells in the desert,the wells are deep (160 m),the BOD of raw water is 60-110 mg/l ,I use the water for power plant and the water treatment used d.m.f with Ro. after 6 month accidentally I found the  BOD is high and research for pretreatment to reduce of BOD.

   OZON plant suggested for reduce to BOD.

   1 Comment

   1. High BOD could be reduced by means of Biological filters upstream the RO/EDR. Reliable and cost-effective.

      1 Comment reply

      1. If possible please send more information about Biological filters for Reduction of BOD

4. Such high BOD with unspecified COD or TOC and SDI will definitely result in fast irreversible (bio)fouling of RO membranes. Hence I recommend to first reduce the BOD by at least 90% for an acceptable economic service life of the RO membranes. We achieve BOD < 3 mg/l by advanced biological treatment for high grade water reuse.

5. if BOD of 60ppm is right, it means the water is contaminated by some organics. but turbidity is very low, so RO will be preferred against EDR as it also removes organic and produce good water quality for drinking water but BOD may cause fouling issue at RO.

6. The well water chemistries are similar. Both EDR and RO would work, it would however depends on what you want to achieve. The EDR would give you high recovery without any pretreatment. For the  RO  option would  however need pretreatment and achieve less recovery. The EDR option normally comes at a premium price but is a very robust solution.

7. The well water chemistries are similar. Both EDR and RO would work, it would however depends on what you want to achieve. The EDR would give you high recovery without any pretreatment. For the  RO  option would  however need pretreatment and achieve less recovery. The EDR option normally comes at a premium price but is a very robust solution.

   1 Comment

   1. The recovery of RO is higher than EDR

8. Best solution would be CORNCOB II.  gabe@imexconsultinggroup.com and I will be glad to get you the proper information.

9. If you send me your email I will send you a paper that is backed up by a working proof of concept plant that can be viewed at anytime.

   4 Comments

   1. Hello Aubrey, could please send me the paper as well. Thanks 

   2. mahmud.elzituni@Mellitahog.ly

   3. Dear Aubrey, could you please send me this paper as well? Munich.Mining@gmail.com

   4. The water TDS is less than 10% of seawater, so RO should work fine, and they should get at least 80+% recovery of permeate with a good RO system. If they need to recover the reject water then the suggestion to use EDR might be reasonable, but it really adds to cost.

10. Since both the water qualities are similar enough, thus in my view a system comprising of Pre-Treatment --> RO is needed and if the TDS of reject goes upto 20000 ppm use EDR and thus take the water from EDR back to RO. It will give u maximum efficiency with minimal power consumptions. 

11. I use magnesium oxide (MgO) prill beads to purify any water. The prill beads come from a deep mine in Nevada. They are processed at 700 degrees which turns them into ceramic beads that do not dissolve in water.

    The beads place a positive charge in the water that shatters the magnetic bond that holds together any contaminants or pollutants (chlorine, fluoride, heavy metals: zinc, copper, lead, chromium-VI, pesticides, radiation, pharmaceuticals, mold, Ecoli, bacterias, etc) and gasses them out of the water. It raises the water pH to 8.7, high alkalinity, high oxygen, and thins the water so that can penetrate the cell membranes and flush out your toxins. As to hydration: 3 Glasses of prill water is equal to drinking 1 gallon of water.

    Great for acid conditions: acid-reflux, heartburn and acne. 

    http://www.PrillyPureWater.net Never dissolves, Never wears out, and Never needs to be re-purchased. One-time investment of $40

    1 Comment

    1. This is a new one on me  that does not seem plausible for all of this substances! Do you have published validated  data?

12. The two waters are not very different. EDR or RO will work for both. However, one of your major concerns will be the corrosivity of the product water. It will be aggressive  toward the pipes and fixtures and leach metals, so you will need to stabilize it by pH adjustment and hardening with lime or limestone.

    1 Comment

    1. Afraid about corrosion use PE 100 in drinking water quality for water transport?

13. For drinking water, use EDR plus pre-treatment and disinfection on the final stage (ex-chlorine or ozone gas). For Cooling System EDR plus post treatment to reduced silica and metal conditioner when circulating. RO could be applicable on both application but the low recovery on reject/concentrate is too much and the fact that high silica would clogged the RO membrane ( there is a solution on high reject by using high efficiency RO membranes and to address silica, very expensive de-ionization process on top of expensive membranes at post & pre-treatment). Hope this will help.

14. I see BOD at 60, and very low TSS of 6 or 2, this is not a ideal case, please check if BOD is 60, TSS cannot be so low, 

15. Well, EDR would be best as the TDS is less then 4K, 

16. Do you have wind of 5m/sec or more?

    We can supply hydraulic windmill that drives reverse osmosis very efficient and 100% sustainable

    www.freshwatermill.comm

    1 Comment

    1. www,freshwatermill.com

17. For cooling water I would recommend Capacitive Deionisation (CapDI). It is an electrcally driven membrane process, that removes hardness without chemicals for regenertion like the use of HCl or NaOH normally used for regenration of IX softeners. It does not increase salinity. Reccommend to go to the Voltea website. Gives a good explanation and it increases the recycle ratio for cooling waters very well against acceptable cost. Good reference base.

    For drinking water it is usually a matter of cost. For this salinity RO and ED are both in the same ball park. So you need other considerations like operability, recovery, scaling and sanitary or pathogen removal.

18. That much sodium will give all of you high blood pressure. Are you in a desert or semi-desert climate? see www.suns-river.com

    2 Comments

    1. The BOD is strange and the salinity is way beyond potability, which is usually below 500 TDS, but some people can tolerate ~1000 TDS, if desperate. Nobody would drink it as is. High blood pressure would be the least of their problems. Their kidneys probably would not survive long enough.

    2. The Suns River solar desalination will yield distilled water free of all minerals, bacteria and BOD. The only other product is dry salt. 99.5 - 100% solar energy.

19. Your BOD is kind of high for water (vs. wastewater) I would use RO as EDR does not remove the BOD (organics).  The silica is not very high so EDR does not have an advantage.  What is F.D. for total hardness?

     

    1 Comment

    1. By using HVCF Technology it is possible to remove BOD.  With MF, UF and RO by using membranes in disc arrangement rather than tubular where there is a dead end that does not allow for a higher permeate.

20. I am interested to explore the differences between the two waters. They are similar enough to be coming from one aquifer but I'd say there is a reason for the disparities - perhaps one is closer to a recharge source? (e.g. a leaking lake, river or canal).

    Hydrogeological issues aside, if the quality of the two waters is stable then a water treatment system could be designed around an analysis of the blended mix. The treated water (with TDS approaching