we have DM plant and for that we used TWO stage RO for Dm feed that second stage RO reject water is around 180 kl/day and that water we want to recover and reject water analysis as below
PH =8.11
TDS =5922
TDS. EVPO. =9200
TH =1928
CAH =924
MGH =1004
ALKP =110
ALKM =1240
CL =3556
SO4 =4626
FE =52.8
SIO2 =137
PO4 =12
please any body suggest us how to recover this water and reduce this quantity.
We at UET provide our customers with recycled water from RO systems as part of our normal business. Looking at the water analysis presented, we should be able to recover 50% of it at the following values: pH = 8; TDS = 800; TH = 700; ALKM = 300; CL- = 500; SIO2 = 50. Should you wish to receive a quotation, please send to me a P&ID diagram of your installation. David
Up to 80-85% of this water can be recycled using a BWRO +SWRO combination. Rest can be used for ash quenching or road spray/ Mine dumping. Other alternative is go for a (MEE) evaporator opex and capex both will be very high.
you can consider using NEXED electro chemical low pressure desalination technology for recovering RO reject water. This is a electrical driven technology and does not get fouled by high concentration of reactive silica present in your reject. RO technology to recover this water is not advisable. There is a technology available to remove reactive silica selectively. You can write to me separately so that I can help you with your problem.
Hello Mr. Riyaz Vohra, in reference to analytical profile submitted by you for your RO reject, we can submit a firm proposal using patented high pressure RO technology of our Principals to you. Kindly share all details with me on my ID (drmodak2007@gmail.com).
recirculate/reuse R.O. reject water after passing it through water conditioner,a device which converts hard water into soft water in natural way without adding any chemicals.
It is not for nothing that this is reject, At higher operational costs you can recover more as per our fellow experts opinion. But in the end you end up with too scaling water. Check out Salttech http://www.salttech.com/ that has many references in the water spares fracking business in the US. SMart way of concentrating brine until salt slurry is produced, without scaling on your walls.
An assumption is you are using two stage (treating the concentrate from RO 1 with RO 2) not two pass (treating permeate from RO 1 with RO 2). A few thoughts. Depending on the feed chemistry and pretreatment before the first stage, you may be able to blend some of the second stage reject back to the feed of the first RO and increase your overall recovery. Treatment of the second stage concentrate may be another option. A Nano system may provide the overall quality of the permeate to send directly back to the feed for the first stage RO. Running at high recovery may provide what you need. Another option is a high pressure RO system to produce a product to feed to one of the stages depending on permeate quality. In both cases some pretreatment may be required to reduce the fouling load identified in the above chemistry.