Hettich India Pvt Ltd
Automatic pH Neutralization integrated with non-MEE based Zero Liquid Discharge System established at electroplating unit in Vadodara.
Company Overview:
- Hettich India Pvt Ltd is a German based MNC having many manufacturing plants all over the world.
- The company is a leading manufacturer of Kitchen baskets and accessories. In their manufacturing process, they adopt a process of electroplating with Ni, Zn, and Cr etc.
Inlet Effluent Detail:
- pH : 5 to 5
- TDS : 25000- 30000 ppm
- Heavy Metals : 10 ppm to 1500 ppm
Objective of Treatment:
- To neutralize the effluent without addition of any chemicals.
- To reduce the TDS load in the reaction tank
- To reduce the heavy metals in the tank
Before Applying the Algae Technology: The Company was generating around 2.5 to 3 KLD effluent with very high TDS and acidic pH. They used to store the effluent as they do not have any facility to treat it. They do not want to go with MEE because the neutralization cost of the effluent was high as well as the operation of MEE is not economical and feasible. Hence we set up the Micro Algae Plant over there. After Applying Micro Algae Technology: After applying the micro Algae Technology, the effluent has been directly taken to the Algae Plant. We have got following results after setting up the plant.
- pH correction :
- The pH of the acidic effluent (0.5-5.9) is neutralized with the use of microalgae. It was observed that during the continuous addition of effluent in algae reaction tank, pH remains in the range of (7-7.5) till the complete addition. After 24 h the pH of the algae pond stabilized in the range of 8-8.5.
- Automatic pH neutralization eliminated the cost of chemical usage for neutralization and hence no sludge generation in treatment plant.
2) Evaporation Rate:
- Evaporation rate according to the ideal design should be 2.5 kl/day/250 sq. mt. But in the existing set up, much higher evapo-transpiration rate than the expected values (>2.5 kl/day) was achieved.
- It has eliminated the requirement of Multi Effect Evaporator (MEE) for the evaporation of high TDS containing acidic/alkaline effluent.
3. TDS Removal :
- Theoretical TDS load was calculated as 2269 kg, however actual lab measured TDS load in the algae till 30th June, 2016 was found to be 527 kg.
- 77% of the TDS has been removed, and there is no sludge formation in the algae pond.
- *Theoretical TDS: A value of TDS when we calculate based on the TDS load that has been added into the system from Day-1 of operation. In control condition, in the absence of algae there is no absorption of TDS, it will be keep on increasing in the system.
- Microalgae play an important role in the degradation, transformation, bioaccumulation of the organic and inorganic constituents of TDS. Therefore, after microalgae based treatment, the value of actual lab measured TDS value is always low
- 4.Heavy Metal Removal :
- Dried algal biomass analysis showed that heavy metals accumulated in the algal biomass through the bioaccumulation/biosorption mechanism with significant reduction in the heavy metal concentration in the treated effluent in the algal reactor.
Compositional Analysis of Algae Biomass harvested from the Tank: -shows the TDS and metals are Bio accumulates in the algae Cells.
