Dosing generally applies to the feeding of chemicals or other liquid additives, in accurately measured small quantities, into a process fluid at intervals to give sufficient time for the chemical to react or show the results. Diaphragm dosing pumps or piston dosing pumps are commonly used. The use of peristaltic or tube dosing pumps is also preferred by some users.
A peristaltic pump is generally preferred by the laundry and catering industries due to the ease of operation and the relatively low cost. These are regarded as the cheapest type of dosing pump for high volume installations where the price of the pump is amortised into the price of the supplied fluid detergent, brightener, softener etc. The peristaltic pump is ideal for measuring the exact dosing for each wash or rinse cycle. Dosing pumps are in reality a metering pump and these terms are used to refer to the same type of pump unit. A dosing pump can be a high pressure pump, however there is a large user base where the dosing of additives is into either no pressure or very low pressure systems.
A reliable dosing pump supplier will offer all types of pumps to suit each application. Acids are commonly dosed into process fluid streams by pumps with the wet component in materials suitable for reliable and safe handling of the specific acids being. The wetted pump chamber is typically PVDF, Poly Propylene, Stainless steel or some other noble metal. Valve seats are also in the same materials with Teflon (PTFE) valve balls and diaphragms making up the most common materials when speaking about diaphragm or piston dosing pumps.
Chemical pumps are available in all types of materials and it is important to specify the acid or alkali or other additives to be dosed.
Aquarium dosing pump
Dosing pumps are also necessary on saltwater aquarium systems if one wishes to automate the calcium and alkalinity dosing. The small SEKO PR1 peristaltic pump is a very popular choice and can be automated with reef timer systems available from saltwater aquarium equipment suppliers. Seko will welcome all enquiries for the aquarium dosing pump arrangement we are able to supply.
Industrial dosing pump
Pumps are not all the same regardless of what industry wisdom tries to preach. When one considers a chemical dosing pump application, the chemical pump one has in mind is not a dosing or metering pump. Dosing pumps are not common applications to most industrial fitters or engineers and do not generally form part of their experiences on a daily basis. Typically dosing pumps would be used in water treatment on chillers, heat exchangers, cooling towers and on the odd occasion in the actual process stream when specific chemicals or additives need to be injected into the system. Dosing pumps can also be used in lubrication applications for grease or oils. Many of these applications are out sourced from the suppliers of the chemicals, additives or lubricants.
Swimming pool dosing pumps
Large swimming pools are generally maintained from a pH and Chlorine point of view by installing chemical dosing pumps. The pumps are controlled by probes for Redox (chlorine values in the water) or Ph which are directly coupled to the suitable Seko dosing pump designed for that application. The pumps are similar to those used in Industrial applications. Generally two pumps one with alkaline dosing and one with acid dosing would be connected to a pH controller and as the demand for either acid or alkaline is registered, the relevant pump will activate. Redox is controlled in a similar manner with liquid chlorine being measured by the dosing pump at the correct dosage based on the redox reading. Seko has a specific range of dosing pumps for Redox and Ph which integrate the redox controller (probe connects directly into the pump) or pH.
The metering pump industry is extremely competitive with many users looking for the cheapest options based on the dosing volume in litres per hour and pressure in bar. Price however cannot be the only consideration and here Seko have poured huge resources in terms of research and development into developing a high quality, economical and efficient, low cost of ownership dosing pump range. As far as economically priced dosing pumps is concerned, Seko have added the correct stock profiles for each country they service. This means that when a specific dosing pump is required, Seko generally have that item ex stock in the country where it is required. Seko dosing pumps are also supported by a dealer network of qualified and experienced people.
Regardless of what one requires a dosing pump for, whether it be an aquarium dosing pump, a swimming pool application or industrial dosing pumps for some specific process additive, Seko generally has the right pump for your application. Dosing is a science which when coupled to the correct metering pump equipment, becomes an art. In terms of a high pressure pump for dosing, Seko is capable of supplying units which inject specific measured doses up to 20 bar.
The range of solenoid driven diaphragm dosing pumps, peristaltic metering pumps and electric motor TEFC electric motor piston and diaphragm dosing pump options ensure a comprehensive solution to most applications in the industry.
