In this paper we study asymptotic behaviour of distributed parameter systems governed
by partial differential equations (abbreviated to PDE). We first review some recently developed results
on the stability analysis of PDE systems by Lyapunov's second method. On constructing Lyapunov functionals
we prove next an asymptotic exponential stability result for a class of symmetric hyperbolic PDE
systems. Then we apply the result to establish exponential stability of various chemical engineering
processes and, in particular, exponential stability of heat exchangers. Through concrete examples we
show how Lyapunov's second method may be extended to stability analysis of nonlinear hyperbolic PDE.
Meanwhile we explain how the method is adapted to the framework of Banach spaces Lp,
$1<p\leq \infty$.