Muhaimin Iqbal
Author

Liquid Waste Valorization To Energy

Advanced Renewable

Tue , 30 Apr 2024 22:04 WIB

This could be good news for processors of industrial liquid waste which is generally not easy to valorize. The majority of liquid waste has a dilemma, its TDS (Total Dissolving Solids) is too small to be processed into energy or other value-added products, but its COD (Chemical Oxygen Demand) is too high, as well as Nitrogen and Phosphorus, so it is dangerous if released into the sewer. So what's the solution?

One solution could be to use liquid waste for microalgae culture, COD, N and P contaminants becomes nutrients for microalgae culture so that microalgae can grow quickly because of it. After the microalage grows for a few days, the TDS automatically increases - it becomes feasible to valorize using one of the reactors that we have made, such as the Regenerative Energy Reactor (RER) which I have previously shared.

After being consumed for microlagae growth, COD, N and P automatically decrease to a safe point and can be released into the sewer. However, for this process, microalgae culture in open ponds does not grow fast enough, and the use of a photo bioreactor (PBR) is not only less fast but also generally expensive.

A special reactor must be made that can grow microalgae in liquid waste very quickly, this is what is called a heterotrophic bioreactor (HBR). HBR is also not actually new, many research institutions and universities already have it, but generally it is very expensive - which is not feasible for handling liquid waste in the real world.

So we designed the HBR in the picture using low cost materials, but still easy to sterilize, it can be feasible for handling liquid waste with the bonus of microlagae biomass. Because the target is waste handling and biomass production, the ideal final product is energy such as syngas, hydrogen, diesel, gasoline, ethanol etc.