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Indicators for sustainability assessment 97

14 Generation of electricity and steam in the
BIG-GTCC cycle
The BIG-GTCC has the objective of producing thermal energy (steam) and
electricity, complementing the conventional stem cogeneration cycle and
sharing the responsibility of meeting the energy demands of the plant.
Fig. 4.15 presents a scheme of the cogeneration system that operates with
the BIG-GTCC cycle, meeting the thermal and power demands of the
processes.
The main parameters utilized in the simulation of the BIG-GTCC cycle
are shown in Table 4.6.
Evaluation of the performance of the different study cases considered
specific indicators that related the energy consumed and produced, compar-
ing the processes with others on the basis of avoided emissions (substitution

Fig. 4.15 Scheme of a sugarcane processing plant with the BIG-GTCC system.

Table 4.6 Parameters adopted in the simulations and calculations (BNDES,
2008; CGEE, 2010; Escobar et al., 2009; Hassunai et al., 2005)
Parameter Value
LHV of syngas (after cleaning) 14.52MJ/kg
LHV of the FT gases 46.90MJ/kg
Pressure of the recovery boiler 85bar
Isentropic efficiency of the steam turbines 78%
Pump efficiency 85%
Boiler efficiency 80%
Pressure of syngas at the turbine inlet 30bar