26 Feb Dosing Pumps
Ensuring the Precise Measure with Dosing Pumps
The ability to measure precise quantities of various materials plays an essential role in our daily lives. For example, many who enjoy watching TV chefs at work will be sure to jot down the precise amounts of each ingredient of a dish that takes their fancy. Likewise, if you have ever had an injection, the nurse or doctor will have carefully measured the dose with a syringe. In many industries, precise metering is also essential and typically relies on the use of dosing pumps.
When most people think of a pump, it is not as a measuring tool but as a transport or transfer system that can deliver a continuous stream of liquid or gas under pressure. Thanks to this type of equipment, for example, a guest can still enjoy a shower when occupying a room on the 20th floor of a high-rise hotel. However, the shower delivers a volume that is determined purely by how long it remains active. So how is it possible for dosing pumps to deliver a fixed quantity of a fluid or gas on demand?
Simply put, their operating mechanism segments the flow of material into equal, measured volumes. The segmentation effect is achieved in one of three ways. Rather than being driven by impeller blades whose rotational speed acts only to determine pressure and flow rate, it is the compressive action of a piston, a diaphragm, or peristaltic contractions similar to that of the intestine that moves the fluid. Each compression delivers one fixed volume via the dosing pump. Because that volume can be predetermined, it is then a simple matter to perform the precise number of compressions required to deliver the desired amount.
The applications for accurate metering of liquids and gases are manifold, and most of these impacts our daily lives. The municipal water treatment plant is a classic example of an application that is crucial to everyone who enjoys the convenience of access to potable water in their homes and offices. At various stages in the treatment process, dosing pumps are to introduce chemicals in quantities that will be effective without compromising water quality or safety. The most well-known of these is the addition of chlorine or one of its compounds to suppress bacterial growth. Because chlorine is highly toxic, precise metering of the chlorination process is crucial.
Though the public is likely to be far less aware of them, water treatment plans conduct other processes in which the role of dosing pumps is crucial. Untreated water is often acidic, so it is necessary to adjust the pH to neutral by adding the correct volume of a sodium hydroxide solution.
Turbidity due to suspended particulate matter is another problem for which the addition of chemicals may sometimes be necessary. Typically, if the turbid water is left to stand in a sedimentation tank long enough, the solid particles will settle to the bottom under the action of gravity. However, colloids in suspension do not sediment naturally so dosing pumps may be necessary to deliver a measured volume of a chemical flocculant that will initiate the process.
A method to deliver precisely metered quantities of various substances is equally essential in sectors ranging from the pharmaceutical, chemical and food and beverages industries to oil and gas. In many cases, it may be necessary to handle materials that are either highly corrosive or abrasive. To meet these more stringent needs, manufacturers have introduced new anti-corrosive and heat-resistant materials to develop a more robust breed of dosing pumps that can stand up to these harsh conditions.
That said, a tougher tool is not always necessary to get the job done. One of the most vulnerable items used throughout many industries is the boiler. Heat is essential for many processes, and boiling water is a simple way to produce it. However, in hard water areas, limescale formation poses a threat to the performance, lifespan, and operational safety of a boiler. Once again, introducing a dosing pump to deliver the correct volume of a suitable water softening agent to the boiler feedwater provides a simple but effective solution.
In summary, there are countless applications for these devices which range in their delivery capacity from millilitres to thousands of litres per hour. They employ various mechanisms to achieve the same ends and are made from materials suitable for the working environment. To ensure choosing the right dosing pumps for your task, consult Prochem Chemical Pump Manufacturers.