<?xml version="1.0"?>
<layout version="0.1.0">
<catalogsearch_result_index>
<reference name="product_list_toolbar">
<action method="addPagerLimit"><mode>grid</mode><limit>30</limit></action>
<action method="addPagerLimit"><mode>list</mode><limit>30</limit></action>
</reference>
</catalogsearch_result_index>
</layout>
The limiter selectbox in pagination toolbar, indeed displays "Show 30" as selected value. But in product list, there are only 9 products displayed in each results page.
setting at backend system > conf > Catalog > catalog>frontend