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                                                                    Exhibit 99.1


                             [AQUA-CHEM, INC. LOGO]



FOR IMMEDIATE RELEASE

December 30, 1998

MILWAUKEE-BASED AQUA-CHEM, INC. CHANGES FISCAL YEAR; ANNOUNCES
PRELIMINARY QUARTER RESULTS

         Milwaukee, WI -- On December 29, 1998, Aqua-Chem, Inc.'s Board of
Directors resolved to change in its fiscal year end to March 31, effective
immediately. Aqua-Chem currently operates on a fiscal year ending December 31,
although certain financial covenants under its bank credit facility are measured
on a fiscal year ending March 31. Management recommended and the Board of
Directors adopted the change in part to harmonize this inconsistency.

         Although Aqua-Chem's financial results for the current quarter ending
December 31, 1998 cannot be estimated with precision and actual performance may
be better or worse than expected, based upon Aqua-Chem's operations for the two
months ended November 30, 1998 and for December, 1998 to date, Aqua-Chem
anticipates that its results of operations for the quarter ending December 31,
1998 will not compare favorably with its results of operations for the quarter
ended December 31, 1997. Aqua-Chem expects that combined net sales for the three
months ending December 31, 1998 (including the net sales of the National
Dynamics division, which was acquired in June of 1998) will be approximately 25%
less than combined net sales of Aqua-Chem and National Dynamics for the same
period in 1997. Although there can be no assurance that sales will increase in
future quarters, it should be noted that Aqua-Chem's order backlog at November
30, 1998 was $83.5 million, an increase of $33.3 million (66%) over order
backlog at November 30, 1997, of which $26.4 million was attributable to the
National Dynamics division which Aqua-Chem did not own in 1997. Aqua-Chem
attributes the anticipated sales decline to an across the board decrease in
demand in the major markets Aqua-Chem serves. As a result, Aqua-Chem may
experience a net loss from operations for the quarter ending December 31, 1998,
and expects to record a net loss for the quarter of approximately $2.5 million,
although the net loss could be in excess of that amount. Despite these
anticipated losses, management believes that Aqua-Chem will continue to maintain
a strong liquidity position.


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                             [AQUA-CHEM, INC. LOGO]



         Management has responded to this situation by accelerating
implementation of a plan that has been under development to reduce expenses
while maintaining Aqua-Chem's competitive position and core business strengths.
Aqua-Chem expects to announce specific elements of this plan as they are
implemented over the next several weeks. Although Aqua-Chem believes that the
plan will be successful in reducing expenses and returning Aqua-Chem's earnings
to historical levels, there can be no assurance that this will be the case, nor
should this information be viewed as indicative of Aqua-Chem's expectations as
to its financial performance for any periods after the current quarter.


         Aqua-Chem, headquartered in Milwaukee with manufacturing facilities
located in the United States, Canada and Mexico, is a world leader in engineered
energy and environmental products and services.

         Aqua-Chem's Cleaver-Brooks division is recognized as the world's
largest manufacturer of commercial and industrial boilers. The Water
Technologies division of Aqua-Chem is known worldwide as a leader in the design
and production of water purification and treatment products and systems for
selected commercial, government, military and industrial applications.


                                      -end-



For further information, contact:

Investor Relations
Aqua-Chem, Inc.
P.O. Box 421
Milwaukee, WI 53201
414-577-2800