Mixers focus on energy efficiency and customer service

Paul Boughton

Mixer suppliers are not only releasing more energy efficient models, but users can now avail themselves of 'test drive' programmes to make sure that what they buy is being optimised for their needs. Sean Ottewell reports.

Going from the lab to production scale has always been a challenge. With the new Silverson Verso it's become less of one. "The Verso reproduces what we can do on a production scale," explains David Rothman, Director of Silverson Machines. "It gives clients the ability to start scaling accurately with smaller volumes than they were able to previously."

A bench-top in-line mixer, the Verso is ideal for pilot-scale or laboratory applications. Controlled from a digital operating touch pad, it offers excellent reproducibility when scaling up, and with a tachometer, ammeter and programmable timer, it provides an accurate and easy method of forecasting the performance of larger in-line mixers under full-scale conditions.

The Verso complements Silverson's lab range of equipment, providing the next step in the scale-up process. The 1hp machine has a self-pumping flow rate of 6.5 US gallons/min (depending on product viscosity).

"We developed the Verso as a direct response to customer requests. Our customers wanted an interim size machine that could allow them to streamline their scale-up process," says Rothman. "Our production scale UHS Series in-line mixers can be used with single or multistage rotor/stator configurations, so we have included that option with the Verso as well."[Page Break]

Interchangeable workheads

A full range of interchangeable workheads is available for the Verso, allowing it to perform the widest range of mixing duties, including blending, emulsifying, homogenising, solubilising, suspending, dispersing, particle size reduction and reaction acceleration.

Then there is the new Silverson Flashmix, the result of innovative design plus years of industry experience. "It is a simple, effective and economical solution for some of the most complex powder/liquid mixing applications in the processing industries," says Peter Matthews, technical manager, Silverson Machines. "In the design, we were able to combine intense high shear, which gives us an agglomerate free mix, with a high rate of powder incorporation of up to 250 pounds/minute."

High powder flow

Ergonomically designed, the Flashmix does not need a feed pump nor does it require adjustment during operation to maintain the high powder flow rate as viscosity increases. Powder incorporation is consistent, batch to batch. Its sanitary design incorporates a European Hygienic Engineering & Design Group (EHEDG) standard and 3-A certified mixer that can be cleaned-in-place. The Flashmix is also energy efficient, requiring 65 per cent less power than similar machines. It is available in two models - the FMX30 with a 10 hp motor and the FMX45 with a 15 hp motor - each with or without a stainless steel sack table.

Silverson has also initiated a 'try before you buy' programme.

The company says that buying a piece of production equipment is a long-term investment, so it stands to reason that customers may want to take it for a test drive. In response to industry needs, it has initiated a free, no-obligation, two-week trial programme that lets customers try out its mixing equipment prior to purchase.

"Customers want to be certain the mixing equipment they are buying is optimal for their production process, and rightfully so," says Matt Smith, vice president of sales, Silverson Machines. "It's an important decision and no small investment."

From years of experience across a wide swath of industries, the high shear mixing experts at Silverson have learned that every mixing application is unique. Because of this, Silverson tests its mixers under the most realistic conditions possible. Then it helps customers choose the right mixer or customises one for their particular application. Knowledge of variables such as raw material characteristics, end product viscosity, batch size and mixing temperature is used to determine the best mixer for each application.[Page Break]

Test facilities

In addition to its trial programme, Silverson maintains two dedicated test facilities - one in the USA in the UK - each equipped with a complete range of laboratory and production scale machines.

At either of these sites, customers can test their applications, try out new products and discuss specific applications with the technical staff.

"We are confident that once a customer tries our equipment, we'll be able to help them optimise their processing," says Smith. "Our high shear mixers can often reduce mixing times up to 90 per cent compared to conventional mixing equipment."

With its MTI Eco-line heating/cooling mixer combination and the radically new Cool tec cooling mixer, MTI Mischtechnik is also firmly focused on minimising energy consumption.

As a result, they provide a high cost-efficiency in the production of dry blends and wood plastic composites (WPC) compounds as well as in other heating and cooling processes - without compromising on product quality.

By combining this equipment with an automatic raw material feeding system, a very efficient heating-/cooling mixer combination with high specific throughput rates can be achieved, says the company.

The new mixer combinations are designed for batch sizes from 60kg up to 1000 kg and throughputs of up to 7500kg/h. Typical uses include compounding of PVC-U for volume-market products such as pipes or profiles, PVC-P for highly filled recipes, and other applications without frequent product changes.

MTI says the Eco-line mixers offer a particularly advantageous combination of high throughput, low energy consumption and attractive pricing, due to careful match of mixer sizes and required mixing power, the use of highly efficient electric drives and optimised usage of cooling water. "Therefore, a changeover from externally sourced dry blends to in-house compounding may pay off after a very short time," notes the company.

For its part, the Cool tec system has been developed in cooperation with Reisner, one of the leading manufacturers of cooling and refrigerating equipment. Offering 30 per cent higher cooling capacity than the existing MTI standard, the Cool tec mixer offers a huge energy-saving potential (up to 25 per cent) and hence, substantial mixing cost savings to the customer.[Page Break]

Key brands

SPX has once again used the annual FoodPro exhibition in Australia to present the latest developments in its key brands, including APV, Waukesha Cherry-Burrell, Gerstenberg Schröder, and Anhydro.

Among the products being highlighted, SPX showcased its new CIP Midi system, Flexmix Liquiverter and Consistator technologies.

The APV CIP MIDI System is designed to accommodate an optional rinse water recovery tank, where the water used for the final rinse is reclaimed to use for the first rinse of the next wash cycle, thus saving considerably on water and effluent.

An additional option provides for a separate rinse water tank which can be used in high-spec applications (for example pharma or bio-tech) to provide high purity final rinse water.

The Flex-Mix Liquiverter is a square-shaped tank with a bottom-mounted, high-speed mixing impeller. The impeller generates an axial flow, which is re-circulated in the tank via the surrounding mixing chamber. This generates high shear forces and turbulence, ensuring effective and homogeneous mixing.

Light to medium processing

The GS Consistator series of scraped surface heat exchangers comprises a line of durable, high-quality machines designed exclusively for light- to medium-duty processing. The units are designed to avoid thermal or mechanical damage to the product (Fig. 1), creating a wide range of products such as chocolate products, cream cheese, quark, ghee, vanaspati, vegetable spreads, filling creams, ketchup, soup and sauces with particles and starch products.

Recent Issues