Providing Sustainable Green Technology Solutions 

Flagship India

Possible Solutions
  • When the water is first taken from underground sources to be used in the soaking operation of the parboiling process, it is either drinkable water or qualities very near to drinkable water. 
  • During the process, pollutant load will increase and hence there will be a lot of increase in TSS, TDS, BOD, COD and turbidity.
  • If we can take them out, the water will become as good as the initial source.

Is it possible? 
Recent projects around the world have treated sewage water and made it drinkable.
Let us simplify our argument. 
If sewage can be made drinkable, then this parboiling rice mill effluent can surely be made reusable. 

According to the literature and research, treatment methods such as:aerobic and anaerobic digestion, adsorption, coagulation and 'aquatic weeds' based methods, membrane bio reactors (MBR) can be used as a single treatment technique or a combined treatment for the removal of the pollutants in Parboiling Rice Mill Effluent.

​Flagship India adopted aerobic digestion, oxidation, coagulation, flocculation, sedimentation, flotation, adsorption, pressure and slow sand and gravel filtration to be followed by membrane technologies and UV or Ozone Treatment methods among others. 

Please visit Our Designs section to have a look at different possibilities of treating Parboiling Rice Mill Effluent and effluent from other similar wet milling industries in individual or combined chemical and biological (microbial and algal) pathways.

Results of chemical treatment:       

  Raw Effluent            After Flocculation     After Filtration 

Effluent Reuse

Reusing Effluent
A discussion about reusing Parboiling Rice Mill Effluent:

​In the rice parboiling industry treated effluent water can be reused as boiler feed water and or in cooling towers of power plant for rice mills who have their captive power plant and obviously back in soaking operation. 

For first two uses, you need to take out all TSS and a lot of TDS so the water is soft enough not to cause any damage to equipments. 

After initial clarification to reduce TSS, BOD and COD, the water will need to be treated with resins and other medias to reduce the selective TDS components. 
  • In case of the water to be reused in soaking, there are many options being tried out, debated and experimented with, in the parboiling rice mill industry. 
  • Some have tried to use the water by only a quick pH correction after it has been drained out of soaking tanks, so that the entrapped heat energy in the water is reused for the next batch (though people use heat exchanger for the same purpose in the effluent releasing line). 
  • Some have tried to reuse the water after chemically or otherwise removing total TSS  but had some BOD, COD and TDS still left in the water. 
  • Some tried that only after the treated water quality reached norms set out by pollution authorities for releasing to external waterways, which will have a lot of TDS still left in the water. ​
  • Some are super critical and hence even want that TDS to be brought down to surface water level ( 300-600 ppm), before they will reuse. 
  • Most of the millers though, have not yet at all thought of reusing the water ! 
  • Rice millers are producing a product for sale and it is their decision at the end of the day, whether to reuse the water or not. 
  • Their primary concerns are that the quality of the rice produced and it's shelf life which should not be compromised at any cost ! 
  • We agree with them totally, but at the same time want to bring it to their notice what is happening around the world, where lot of industries are reusing their effluent by adopting modern technologies. 

Millers are going to be the one to finally choose their point of reuse.

We are not experts in parboiling technology. 
So we would advice the rice millers to consult their own technologists on the issue of reusable water quality. 
We can provide the rice millers with treated water of any quality they need.