General Mixer Selection

 

STATIC MIXERS – FIRST CONSIDERED

The first step in mixer selection is to establish if a static mixer can be used in the mixing process to save power consumption in the plant by use of an existing pressure head. Static mixers are also known as motionless mixers since they consist of fixed elements fitted into a main feed pipe or feed channel and the elements remain fixed and thus static in the pipe or channel. The flowing streams are intimately mixed in the static elements by flow diversions and re-directed flow paths.

Static mixers are used in more advanced applications for specific services, but in simple applications, such as where there is a small pigment stream being added to a liquid feed stream, or an additive liquid feed stream is being blended into a main feed stream, then static mixers should be considered. The main applications are for clean fluids in continuous stream feeds, where the adder stream is generally of smaller flow rate than the main flow stream.

Static mixers do have some limited applications in solids mixing, but as a rule their applications are to be found in liquid-liquid mixing, of continuous flow. If the choice is not obvious and proven, consult with Jones Industrial Mixers for a full application consideration and, if suitable, static mixer design.

PLANNING YOUR BATCH SIZE

The second step in mixer selection is to determine the design batch size. We refer you to our article on batch size selection on this site to enable a thorough assessment of the selection factors and constraints.

SETTING OF YOUR MIXING OBJECTIVES

The third step in mixer selection is to set out your mixing objectives. This can be a fairly simple statement, but it will need to be thorough where difficult mixing needs or processes arise and where special feed conditions, heating, cooling or any other special requirements arise. Also important are requirements for mixing under pressure, vacuum, or hazardous products handling.

We also recommend a reading of our article on mixing objectives on this site to enable a full consideration of your true and detailed mixing objectives. This will also ensure an understanding of the difficulty of setting precise mixing objectives in many cases.

DETERMINING YOUR KEY DESIGN INPUTS

Jones have prepared a standard mixer enquiry data sheet that enables a useful listing of all the necessary parameters to consider and detail. Please prepare this enquiry sheet and email of fax this sheet to us for a design consideration. We also recommend you complete the enquiry sheet in conjunction with a reading of our ‘Tips for mixer selection’ also in this section of the site.

These guidelines and notes are presented as general guides only and no warranty is implied or provided.