Wastewater Treatment – A New Technology Promises Higher Efficiency at Lower Cost
A new technology in wastewater treatment, called Advanced Immobilized Cell Reactor technology, available now, promises benefits like:
* Up to 25% lower plant cost
* Up to 50% lower operating costs
* Up to 50% lower maintenance costs
* Up to 90% less sludge production
* Up to 60% smaller footprint (can even be set up underground or on the roof)
* Speedy plant construction (2 to 6 weeks for small/medium sized plants)
* Insures high purity level of treated water, as below:
(i) BOD (Biological Oxygen Demand): less than 5 mg/Liter,
(ii) COD (Chemical Oxygen Demand): less than 60 mg/Liter (or even better)
* Meets all input specifications of wastewater from large industries/ cities/ towns.
It has varied applications:
* Small sizes for both industrial and domestic applications.
* Can also be created in standard sized, skid-mounted form
* Can be readily installed cost effectively in small homes, individual/ small business establishments like car washes, bakeries, restaurants, mini-hotels, etc., and plants for rural areas.
* Can also be installed with Sludge-handling model or Sludge-absorption model for Domestic use
* Can be used to facilitate re-use of water for purposes like golf courses, toilets, gardening, and even washing.
* Or just let off the treated water to recharge the ground water.
What’s more, it is cost effective to implement small Plants using this technology anywhere in the world, with mostly indigenous material and conforming to local standards. This technology has been implemented successfully in many locations.
The Advanced ‘Immobilized Cell Reactor’ technology can also be applied to the treatment of domestic wastewater. The presence of organic, inorganic chemicals, and organisms, both pathogenic and non-pathogenic in nature, make domestic wastewater complex. Conventional biological treatment systems do not remove dissolved organics and microorganisms satisfactorily. Moreover, the systems are not efficient enough to recover the water for reuse purpose.
Integrated biological and chemical oxidation happens in a single reactor. The reactor consists of a tall column packed with activated carbon. The activated carbon is immobilized with chemo autotrophs. Oxygen required for the oxidation of organics in wastewater is supplied in the form of compressed air from the bottom of the reactor. The counter-current movement of the liquid and air streams enables the dissolved organics to undergo oxidation and desorb the converted products, so that the activated carbon maintains its activity throughout the operation. The domestic wastewater treated through Advanced ‘Immobilized Cell Reactor’ system has reduced BOD by 94%, COD by 90% and sulfide by 100%.
However, the technology also has some limitations:
* Permeability index is less than that of sand filters
* Maximum organic loading rate allowed is limited
* Performance is limited by the presence of suspended solids in wastewater.
* Anaerobic treatment is an essential unit of operation before proceeding to Advanced ‘Immobilized Cell Reactor’ reactor to reduce the viscosity of wastewater and eliminate colloidal solids.
* Multiple modules are required to handle huge volumes instead of a single module.
All in all, the Advanced ‘Immobilized Cell Reactor’ technology can be applied across a wide spectrum of industries. It has performed at a credible level for the removal of organics estimated as BOD and COD from wastewater generated in leather garment manufacturing, textile-yarn-dyeing , sago, chemical, and pharmaceutical industries.