Preparation of pyrogen-free water

A method for producing pyrogen-free water while consuming a minimum of energy, comprising the steps of:

• filling a container with water which contains pyrogens to a volume sufficient to accomodate expansion of said water upon subsequent heating;
• sealing said volume of water within said container;
• heating said volume of water to a temperature of at least 180.degree. C while simultaneously controlling the pressure of said volume of said water so as to maintain said water substantially entirely in a liquid state thereby thermally degrading said pyrogens to produce pyrogen-free water without any appreciable vaporization of said water;
• reducing the pressure and temperature of said volume of said water to ambient pressure and temperature, respectively;
• and removing said water from said container for use.

A system for producing pyrogen-free water comprising:

• first sealable container means for containing a first volume of water,
• second sealable container means for containing a second volume of water,
• first means to feed a first pyrogen-containing water stream to said first container means;
• said first means comprising first preheater means to indirectly exchange heat between said first stream and said second volume,
• second means to feed a second pyrogen-containing water stream to said second container means, said second means comprising second preheater means to indirectly exchange heat between said second stream and said first volume,
• means to heat said first and second volumes to temperatures of at least 180.degree. C,
• means to maintain said first and second volumes substantially entirely in a liquid state at said temperatures, thereby to thermally degrade pyrogens within said water so as to produce pyrogen-free water therefrom,
• first outlet means to withdraw said pyrogen-free water from said first container means,
• second outlet means to withdraw said pyrogen-free water from said second container means.