Muhaimin Iqbal
Author

Things To Do With Our Waste

Advanced Renewable

Tue , 23 Apr 2024 21:28 WIB

The waste crisis in a number of cities has reached its peak, a number of regional officials who had discussions with us - hame the similar the tone, if they could just eliminate this waste from their cities - that would be an achievement. There is even a large budget to be able to remove this rubbish from their area. The question is whether this rubbish should be thrown away?

So the graph below is a solution options that not only eliminates waste, but turns waste into high value products, here I am not including waste that is processed into RDF (Refuse Derived Fuel) for example - because it is not included in high value products.

Starting number two from the left, that's the trash position, the value is negative - because we have to pay people to accept it, but the energy content is quite high. The three tons of waste that we use as a benchmark here has an energy content of around 42 GJ. The simplest processing is to convert it into charcoal, from 3 tons of waste the mass will reduce to just 1 ton, the energy will also decrease because some of it is wasted, only around 30 GJ remains. But the value of charcoal is already positive, from negative waste to positive, 1 ton of charcoal is worth $ 200.-

From the same waste or charcoal, we can increase the energy again - that is, when we heat the carbon and combine it with hot steam, the water gas reactions, the result is CO and H2 or what is called syngas, from syngas we can make DME, 1 ton of charcoal can become 1.92 tons DME with a total energy content of 55 GJ, on the market the selling price is around US$ 737,-

If it is made into methanol, it will be 2.67 tons of methanol with a total energy of 53 GJ, the selling value is around US$ 933.-. Or to 1.92 tonnes of ethanol with an energy content of 51 GJ, the total price increases slightly to US$ 958.-. It can also be used to produce pure hydrogen, the mass will drop to only 0.33 tons, and the energy is only 40 GJ, but the price increases to a total of US$ 990,-

What's interesting is that the final product we are aiming for is regenerative hydrocarbon fuel such as gasoline and LPG - both of which are needed massively throughout the world. With the same amount of 3 tons of waste or 1 ton of charcoal, 1.18 tons of gasoline can be produced, with a total energy of 53 GJ with a selling price of around US$ 1,200.

And the most interesting thing is that when the waste is processed into LPG, the 3 tons of waste mentioned above can produce 1.22 tons of LPG with a total energy of 60 GJ, without subsidies the price is around US$ 1,400, - Because this is the most interesting, we have completed the reactor design first as in the image below.

With so many choices, will we still continue to fight hard to simply eliminate this waste? Of course, to produce these products requires investment, but we can be sure that the investment is only a fractions of the costs needed to continue developing new landfills.