Dynamic evaluation of environmental impact for three-way catalytic converter with temporal variation life cycle method

Purpose A three-way catalytic converter (TWC) is a type of pollution control product (PCP) that has been widely used to reduce the emission of carbon monoxide (CO), total hydrocarbon (THC), and nitrogen oxides (NOx) from vehicles. TWC's decreasing removal efficiency as a result of their aging condition can have a substantial impact on their environmental benefits. The goal of this paper is to evaluate the dynamic environmental impacts of TWC during its whole life cycle. Methods Dynamic emission factors of pollutants from the rapid aging (RA) test and the real vehicle aging (RVA) test were firstly analyzed. Then, the dynamic environmental benefits and dynamic environmental burdens of TWC during its whole life cycle were evaluated by a dynamic life cycle assessment (DLCA) method. Impact categories assessed included global warming potentials (GWP), acidification potentials (AP), human toxicity potentials (HTP), photochemical smog potentials (POCP), and abiotic resource depletion potentials (ADPs). Results and discussion Dynamic emission factors of vehicle pollutants collected from the rapid aging (RA) test and the real vehicle aging (RVA) test indicate that CO had the highest emission amounts compared to NOx and THC. Results in AP, HTP, and POCP showed that the environmental benefits of TWC in the RVA test were 76.24, 1.03, and 2743 times greater than its burdens. The difference in AP, HTP, and POCP between RVA and RA tests was 0.39%, 0.39%, and 0.97%, showing no significant variations from these two tests to evaluate the environmental benefits. Dynamic environmental burdens allowed for a 51.36% increase in HTP compared to static environmental burdens of TWC. Conclusions Both RVA and RA tests are suitable methods to acquire the dynamic data in the dynamic life cycle assessment of TWC. Our results proved the more precise evaluation of dynamic environmental burdens in reflecting the performance of TWC in real driving circumstances.

Automated summary

This paper evaluates the dynamic environmental impacts of a three-way catalytic converter (TWC) throughout its life cycle. The study analyzes the dynamic emission factors of pollutants from rapid aging and real vehicle aging tests, and evaluates the environmental benefits and burdens of TWC using a dynamic life cycle assessment method. The results show that TWC has significant environmental benefits, with little variation between tests.