Combining the advantages of the natural circulation method of distillation with the separation of pyrogens by forcing the steam produced to make a number of rigorous turns, the Pharmatec Multiple-Effect Water Still produces the highest quality Water-For-Injection regardless of the quality of water feeding the unit.
MODEL Distillate Capacity at Different Heating Steam Pressures
High Energy Efficiency
The Pharmatec Multiple-Effect Water Still is one of the most energy efficient means for creating Water-For-Injection on the market today. The distillation process takes place in a number of columns (usually 3 – 8) that are connected in series. Each column is equipped with an evaporator and separator. Only the first column evaporator requires an external heat source such as plant steam or electricity. As feed water evaporates in the evaporator located at the bottom of the first column, it travels as steam up to the first stage separator where the steam is directed in a series of turns. Water droplets and impurities are stripped off, the steam then continue to the second stage separator where it is directed in a series 180 degrees turns to ensure dry pyrogen free pure steam. The pure steam that was created in the first column enters the second column to act as the heating source for the second evaporator. This process is continued on through each column, reusing the energy created in the previous column. The greater the number of columns, the less external energy required.
The Pharmatec evaporator utilizes a design that allows the tube bundle of the tube-and-shell heat exchanger to be totally immersed in feed water. The shell side of the evaporator contains the heating steam. Only after the tube side of the evaporator is filled with water is the plant steam applied to the shell side and, as a result, the feed water is brought up to temperature without shocking the evaporator welds. This safe design allows for less expansion and contraction of
the joints in the tube bundle, which results in longer life of the evaporator.
Less Water Consumption
The Pharmatec Water Still consumes less feed water than most all other water stills available. Utilizing a unique wetted evaporator and natural circulation design, only 3 to 5% of the total feed water is needed to carry the impurities to drain. Only a small amount of cooling water is required to accomplish the final cooling of the distillate as most of the cooling is accomplished by the feed water.