Sanitary Progressing Cavity Pumps For Lecithin and Cream Transfer 

In our latest case study, we’re discussing three new hygienic progressing cavity pumps we supplied to a UK food manufacturer who needed proven, reliable food grade pumps for the smooth and uninterrupted transfer of lecithin and cream in their production facility.

So what is Lecithin?

Found in both animal and plant tissue, lecithin is a generic term which is used to describe any type of yellow-brownish fatty substance. Occurring naturally, lecithin comes from egg yolks, corn, marine foods, milk, rapeseed, cottonseed, soybeans and sunflowers; and is amphiphilic, meaning that it attracts both water and fatty materials.

In the human body, it’s a mixture of fats which are essential to many of our body’s processes. Lecithin is used in the metabolic process and to move fats around our bodies. In our diet, Lecithin is the main source of choline, a nutrient similar to the various B vitamins. It’s converted into acetylcholine, a substance that relays nerve impulses.

In food manufacturing, Lecithin is commonly used as a food additive to combine foods. It’s also a natural emulsifier often used in many everyday foods, it keeps flavour in mixtures and is an antioxidant.

Where is it used commercially?

Lecithin plays a big part in animal feed, pharmaceuticals, paints, and other industrial applications, bringing different benefits for the individual processes.

• In the animal feed industry, it enriches fat and protein and helps to compress or mould animal feedstuffs into pellets.

• In pharmaceuticals, it’s used as a wetting and stabilising agent and as a choline enrichment carrier. It assists with emulsification and encapsulation and is a good dispersing agent. In addition, it can be used in the production of intravenous fat infusions and for therapeutic use in medical environments.

• In the paints industry, it can be used to create protective coatings for surfaces which carry paint and printing ink. It helps prevent rust spreading, is a colour intensifying agent and dispersing aid. It also stops the hard settling of pigments, removes foam from water-based paints, and assists with the fast dispersal of latex-based paints.

•  In plastics, Lecithin can be used as a release agent. It’s an anti-gumming agent in petrol, an anti-sludge additive in motor lubricants, and a spreading agent, emulsifier and antioxidant in rubber, textiles and other industries.

How is it made?

Lecithin is a mixture of phospholipids which is found in plant and animal tissues and is vital for proper biological function. In fact, phospholipids are a major part of all cell membranes.

Commercial lecithin is derived from vegetable oils, typically soybean oil, through a production process that starts with degumming. Here, the crude soybean oil is mixed with up to 3% water or steam and slowly agitated to add water to the lecithin. 

Next, the hydrated gums are taken out by being spun in a centrifuge, and the wet gums are dried by batch or film drying. 

The final steps is to filter, deodorise, and divide up the lecithin, removing the oil residues.

Our specification for this project

Here at North Ridge Pumps, we’re not restricted to just one type of pump technology.

We use our wide-ranging expertise to provide a tailor-made solution, not something straight off the shelf. We choose the best pump for each specific client and job – and offering the lowest lifetime cost.

For this application, we specified three of our DX range of hygienic progressing cavity pumps.

Our DX sanitary progressing cavity pump series are state-of-the-art units specifically designed to meet the exacting requirements of the food, pharmaceuticals, chemicals and cosmetics industries.

The whole pump design complies with EHEDG and 3A standards to ensure the highest levels of sanitisation.

Both organisations, the European Hygienic Engineering & Design Group (EHEDG) and 3-A Sanitary Standards develop guidelines for hygienic design in the food and pharmaceutical industries. While the two bodies have different approaches, they both have the same basic hygiene principles, and their documents are designed to complement each other.

High hygiene standards

The geometry of the pumps is designed precisely to provide the best sanitisation characteristics thanks to the design of the casing and the rotating parts. This allows for maximum drainage, and the avoidance of dead zones and stagnation to eliminate bacteria forming.

In short, we manufacture every component to the highest level of finish and utmost cleanliness.

The parts in contact with the product being transferred can be constructed from AISI 304 or AISI 316 stainless steel. AISI 304 is good for applications that need strong corrosion resistance, formability and weldability. AISI 316 is better for superior heat resistance and use in highly corrosive environments, especially those with chlorides.

All parts have excellent finishes, and the casings are polished to make sure that the surfaces are completely sanitised. As well as the parts that touch the product, the block and base plate too are made of stainless steel AISI 304.

These pumps are top rated for adhering to Clean-in-Place (CIP) and Sterilisation-in-Place (SIP) automated processes, meaning that the units can be cleaned and sterilised without the need for disassembly. These systems are widely used in the food and pharmaceuticals industry to ensure total hygiene and sterilisation of critical processes.

Plus innovative product features

• Patented pin joint

 Our patented pin-type joint, the heart of this single screw pump, is the most advanced of its kind on the market. It gives customers greater product longevity and reliability as well as reduced maintenance costs, and combines exceptional compactness with unrivalled strength.

What’s more, replacing worn parts is cheap and easy thanks to the bushes in the worn zones, which remove the need for costly replacement of the rotor, drive shaft and female drive shaft.

• Low pulsating flow

In this range of sanitary progressing cavity pumps, the tensional stress and pulsating flow are very low. In fact, the low operating rotations and the axial pump design keep the effects of the centrifuge to a minimum.

This is good for operation as low pulsating flow reduces shear and helps ensure that fluids and components are handled more gently. It also minimises the stress and fatigue on system components and helps prevent damage. 

• Modularity

This entire pump range works around the concept of modularity. The base plate, casing, seals, housing, hydraulic parts and drive shafts are all available in several variants without changing the overall structure of the pump, while also keeping the main spare parts standard.

• Shaft sealing

For maximum flexibility and versatility, a number of different sealing systems can be installed to suit different applications. These include a single acting mechanical seal with quench, and a double acting mechanical seal with the option of back-to-back or tandem.

In addition, the various types of mechanical seals can all be mixed and matched on the standard pump, depending on each individual application.

•  Easy maintenance

These pumps are specifically designed to require minimum maintenance and have only a small number of parts which need replacing. In particular, the joint bushes can be switched without having to replace the shafts and rotors. This means that maintenance costs are massively reduced and the lifetime running costs of the pump are very competitive.

All in all, with high performance levels, exceptional operating efficiency, durability, reliability and low running costs, our DX hygienic progressing cavity pumps offer users a technologically advanced solution for a variety of applications.

Why this pump was selected

The brief from our client was to specify a pump which would smoothly transfer the cream and lecithin at a range of flows from 10l an hour to 10m³h at pressures up to 8 bar.

We chose these pumps because of their low pulsating, shear-sensitive flow and high hygiene rating.  Delivering consistent product transfer at the required flow rates, regardless of any changes in viscosity or pressure.

In short, the DX sanitary progressing cavity pumps will ensure that fats in the cream and lecithin will remain suspended, will spread evenly and remain unchanged from source right through to delivery.

Have an application needing the transfer, circulation or injection of any liquid of any viscosity and need help and advice? Contact North Ridge Pumps to see how we can help.