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10 Illustrative Case Study
material flows (production of reactant chemicals and management of resulting waste
solvents) and the energy required for heating the reactor.
10.3.1 Goal and Scope Definition (Phase 1)
In the first phase, the goal and scope of the LCA need to be defined. Assume that
this LCA was requested to be completed internally within the company in order
to understand the source of the largest environmental impacts within this synthesis
step and to later compare the total impacts of this step to an alternative design for
the step. The impact categories requested to be used are climate change, ecotoxicity
and human toxicity, and cumulative energy demand (CED). The system boundaries
for the LCA have been requested to ideally cover the production of the reactants,
heating of the batch reactor during the synthesis step, and management of wastes
via either disposal (incineration) or reuse. For the sake of simplicity, only the waste
solvents are quantitatively treated in this case study.
Task: Use what is known about the requested goal and scope of the LCA (from the
description above) to answer the following:
(a) What is the objective of the LCA?
(b) What system boundaries can be defined?
(c) What functional unit could be used in the LCA to help compare with future
alternative reaction step designs?
(d) Who is the target audience for the results of this LCA? What is their expected
level of expertise, and how would this affect how the results of the LCA will be
presented?
10.3.2 Inventory Analysis (Phase 2)
The second phase within LCA is to compile a life cycle inventory (LCI) of the
system under review. The LCI is a list of the quantified resources and emissions that
move into and out of the system boundary. Given the set scope of this particular
LCA, this would include the reactants, solvents, heating energy, and products and
waste solvents generated (see Fig. 10.3).
Task: Using the information and data from the process risk assessment that describe
this process step, construct a simple LCI table that includes (1) the amount of each
reactant and solvent used in the production of one batch of 3-amino-2-isopropylthio
benzonitrile, (2) the amount of the main product and the waste solvents produced
during the process (ignore the generation of Cu 2 S, NaCl, and HCN as well as any
excess reactants), and (3) the energy required via steam to heat the reaction mass to
190 ◦ C.
10 Illustrative Case Study
material flows (production of reactant chemicals and management of resulting waste
solvents) and the energy required for heating the reactor.
10.3.1 Goal and Scope Definition (Phase 1)
In the first phase, the goal and scope of the LCA need to be defined. Assume that
this LCA was requested to be completed internally within the company in order
to understand the source of the largest environmental impacts within this synthesis
step and to later compare the total impacts of this step to an alternative design for
the step. The impact categories requested to be used are climate change, ecotoxicity
and human toxicity, and cumulative energy demand (CED). The system boundaries
for the LCA have been requested to ideally cover the production of the reactants,
heating of the batch reactor during the synthesis step, and management of wastes
via either disposal (incineration) or reuse. For the sake of simplicity, only the waste
solvents are quantitatively treated in this case study.
Task: Use what is known about the requested goal and scope of the LCA (from the
description above) to answer the following:
(a) What is the objective of the LCA?
(b) What system boundaries can be defined?
(c) What functional unit could be used in the LCA to help compare with future
alternative reaction step designs?
(d) Who is the target audience for the results of this LCA? What is their expected
level of expertise, and how would this affect how the results of the LCA will be
presented?
10.3.2 Inventory Analysis (Phase 2)
The second phase within LCA is to compile a life cycle inventory (LCI) of the
system under review. The LCI is a list of the quantified resources and emissions that
move into and out of the system boundary. Given the set scope of this particular
LCA, this would include the reactants, solvents, heating energy, and products and
waste solvents generated (see Fig. 10.3).
Task: Using the information and data from the process risk assessment that describe
this process step, construct a simple LCI table that includes (1) the amount of each
reactant and solvent used in the production of one batch of 3-amino-2-isopropylthio
benzonitrile, (2) the amount of the main product and the waste solvents produced
during the process (ignore the generation of Cu 2 S, NaCl, and HCN as well as any
excess reactants), and (3) the energy required via steam to heat the reaction mass to
190 ◦ C.