The cost effectiveness of the biomass conversion processes depend on numerous factors such as cost of selected raw material, choice of reactor, energy input requirement and separation processes required to retrieve the products. Hence, it is difficult to ascertain the cost effectiveness of either HTC or Pyrolysis without a detailed techno-economic analysis comparing both processes.
Let's assume that we have wastewater sludge and we need to change to char. As we know, if we use pyrolysis , it will be biochar and for HTC, it will be hydrochar.
In addition, let's consider that we need to have the same characteristics of products from both methods.
So, which one is energy intensive and time consume to have the same properties of the product?
As reserach group coordinator of cost enginerring publishing good rearch paper about the same , Bemgba Bevan Nyakuma is correct infect we can do jointly as i consider this very important questions , Admiting the same reactor size , as you know pyrolysis can be operated via self gasification auto termal , HTC cannot , thus enegy wise , HTC may too need highpresure heat recover more energy consuming one . Related kinetics as HTC indeed vey high temperture lower time they say advanages more advantages , but if operate pyrolysis too fast one , this too pyrolysis will not be bad .Finaly acoding famous lang factor economical eng principles , you may need 60 porcent less less investment compared to HTC as highpressure steam is used in HTC, thus for decentralised small scale pyrolysis with it flexibility to process diverse feedsticks , even plastics can be economical viable reated micro , mini smart grid , therei no advantages significant , yet one need detailed study..See our publish work , all related to economical viabilty study too
Indeed cost effectiveness depends on many factors still there are some valid reasons to select HTC method interms of operational cost to be more cheaper as compared to pyrolysis. as your question is only for the process selection so i will suggest HTC to be more cost effective that is due to , low energy consumption, less occupied space, smaller reactor without providing any activation gas (need to flush only) , water is used for synthesis, produce variable byproducts, low maintenance etc.