Design of tri-generation systems
To solve the problem of existing CHP system, a tri-generation
system is proposed to significantly improve the efficiency of thermal
utilization. The proposed scheme is to use the excess thermal energy
of the CHP system to drive a lithium-bromide absorption chiller. Its
chilledwater output is for space cooling of power house, office buildings
or residential buildings nearby.
According to the different driving heat sources, absorption chillers
can be classified into four types, namely hot-water driven, flue
gas driven, steam driven and direct-fired absorption chiller. For the
existing CHP system, the heat sources available for driving the chiller
include the flue gas and jacket hot water. For different kinds of absorption
chillers, the temperature requirements for the heat sources
are different, which determine the design scheme of each trigeneration
system as listed in Table 2. In the original CHP system
(Fig. 1), the low temperature heat source, such as 180 °C flue gas
and 85.9 °C hot water, can only drive the single effect absorption
chiller. The high temperature 450 °C flue gas, in theory, can be further
utilized in four ways: heating, cooling, producing water vapor and