The procedure environment like algorithm is already a float so you cannot place it inside figure or table directly. See this discussion for more details.
You can place your procedures in minipage environment and add caption using captionof command from caption package. and then enclose them in figure environment as follows,
\documentclass{article}
\usepackage{algorithm2e}
\begin{document}
\begin{figure}
\begin{minipage}{\linewidth}
\begin{procedure}[H]
some code \;
\caption{abc (n).}
\end{procedure}
\end{minipage}
\begin{minipage}{\linewidth}
\begin{procedure}[H]
some code \;
\caption{abc (n).}
\end{procedure}
\end{minipage}
\caption{some procedures.}
\end{figure}
\end{document}

You may also want to look at the answers for this question.
{}to format the code -- refer to Markdown help for more detauls. And keep in mind that while code snippets are useful in explanations, it is always best to compose a fully compilable MWE that illustrates the problem including the\documentclassand all the appropriate packages. While solving problems is fun, setting them up is not. Then those trying to help can simply cut and paste your MWE and get started on solving problem. – Peter Grill Nov 03 '12 at 06:34