A new standard process system enables dilution of raw 70% high active down to 27% low active in line and on demand. Mary Anne Johnson explains the benefits
As the demand for personal toiletries, domestic cleansing products and industrial detergents increases, greater demands are being placed on the formulators and users of surfactants to find more environmentally acceptable and efficient methods of production. Natural and synthetic surfactants represent a major percentage of the finished product’s price. Dilution of high active surfactants is desirable, maintaining costs and producing milder and more environmentally acceptable products.
One major factor contributing to the high cost and environmental impact of buying in diluted high active is the cost of transporting what is essentially water.
Historically, diluting high active has involved bringing together the raw material and water in a mixing tank as and when required. This method is not without its problems, such as high foaming and accurate temperature control. Individual batch production is inflexible and time consuming, so a system that can produce diluted active to exact specifications on demand should be an attractive proposition.
SPX Process Equipment is offering formulators and users a standard process system for diluting raw 70% high active down to 27% low active in line and on demand. This system also overcomes the problems of high foaming and gelling, plus it does not require the process water to be heated. Mike Scott, systems product manager, Bran + Luebbe says that the development of this standard High Active Diluter system was a logical step for the company to take, having supplied processing systems to manufacturers all over the world.
Allowing users to produce diluted active to the exact specification as needed reduces purchase costs for manufacturers and shortens production times. The High Active Diluter uses standard Bran + Luebbe products and technologies and is available in 1, 4, 7 and 12 tonne/hour capacities.
The system’s principle components are: a high active storage tank, three-head metering pump, preservative holding tank, Pentax mixer, suction and discharge lines, pressure relief valve and control panel, all of which are mounted on a base frame, with optional extras such as refractometer, flowmeter or pH meter. Trace heating and lagging can also be provided.
The Bran + Luebbe metering pump pumps the high active, preservative and water accurately in correct proportions. Each pumphead has its own stroke length setting, allowing the individual adjustment of the flowrate of any one of the liquids. A a separate preservative pump can be supplied, allowing the preservative to be switched on or off independently of the main unit.
In operation, the water and high active are brought together by the metering pump and meet in the Pentax mixer where instant dilution occurs. This high shear dynamic mixer takes the active down through the thick ‘m-phase’ at 30-60% and then down to 27%. This requires consistently accurate raw material feeding from the pumpheads.
As all users have different requirements, a variety of add-on components are available. For instance, a force fed system can be supplied to ensure good pump efficiency throughout any level changes in the high active tank or changes in raw material temperature/viscosity.
The system can also be supplied with a refractometer placed in the final discharge line for active % monitoring and alarm, together with active % closed-loop control. Percentage monitoring and alarm allows the user to alter the stroke length of the high active pumphead manually and provides automatic system shutdown in an emergency.
For closed loop control, the active % signal is linked to a PLC, which monitors the level accurate to +/-0.1% active. The final product is maintained within preset error bands. Low and high active % alarms are activated should there be a deviation and shut down is automatic.
The possible need for flowmeter monitoring and batching has also been considered. Where required a flowmeter is placed in the final discharge of 27% active, reporting the unit’s flow rate and allowing pre-set batch quantities of 27% active to be discharged by the unit if required.
Contact
Mary Anne Johnson, SPX 216, UK
e-mail: maryanne.johnson@
processequipment.spx.com