Green Energy from Wastes - project, lecture, laboratory - Hryb sem. zimowy 2026/2027

Green Energy from Wastes – project - Wojciech Hryb, PhD Eng.

Perform basic calculations for a biogas plant designed for the fermentation or co-fermentation of the following components (substrates):

Section 1: 44 000,0 Mg/year sewage sludge (90% moisture content),

Section 2: 7 900,0 Mg/year potato tops/leaves, 8 150,0 Mg/year vegetable waste and residues,

Section 3: 25 100,0 Mg/year potato distillery spent wash,

Section 4: 34 750,0 Mg/year kitchen waste,

Section 5: 27 900,0 Mg/year kitchen waste, 5 100,0 Mg/year urban green waste,

Section 6: 19 750,0 Mg/year cattle slurry, 18 500,0 Mg/year pig slurry,

Section 7: 28 900,0 Mg/year brewer's spent grain,

Section 8: 24 750,0 Mg/year fruit waste and residues,

Section 9: 24 900,0 Mg/year maize silage.

Based on a literature review (identifying biogas plants in Poland and Europe operating on the same substrates for biogas production), select the optimal technology variant for the given waste types (considering the number of process stages, process temperature, loading mode, and dry matter content of the substrates).

Calculate annual methane production based on empirical data. Knowing the annual methane production makes it possible to calculate the energy generated by a biogas plant. Given the current green energy support system in Poland, the most advantageous method of utilizing biogas is the combined generation of electricity and heat. When calculating energy production via cogeneration, the following parameters must be taken into account:

•          the calorific value of the methane contained in the biogas,

•          the unit's efficiency (thermal and electrical),

•          the unit's annual operating time,

•          the proportion of the heat generated annually that is used for internal needs,

•          the proportion of the electricity generated that is used for internal needs.

Perform basic calculations to determine the capacity of the cogeneration units and to estimate the net production of electricity and heat for sale.

Calculate: annual methane production, annual energy production, theoretical thermal power, theoretical electrical power, gross heat production, process heat consumption, net heat production, gross electricity production, process electricity consumption, and net electricity production.

Perform basic calculations to determine the technical parameters of the equipment components for the planned installations: volume of the pre-treatment tank(s) and/or silos, volume of the fermentation chamber, nominal power of the generator in the cogeneration system, volume of the biogas storage tank, volume of the digestate storage tank, hydraulic retention time (HRT), and organic loading rate (OLR) of the fermentation chamber.

Optionally, propose a technology for upgrading biogas to biomethane—justify your choice and suggest a method for utilizing the biomethane. Make a preliminary assessment as to whether producing biogas or biomethane would be more profitable from the plant owner's perspective—justify your choice.

Literature:

 

Wojciech Hryb, PhD Eng.