Achieving greater efficiencies with pneumatic conveying lines

This kind of equipment is built to last, so unless you are very unlucky – or if you haven’t been keeping up your preventive maintenance strategy – then it’s not an area of your process that you would usually replace. However, if you are looking to gain efficiency either by increasing volume or speed of transport, reducing energy consumption, or by regaining control of your maintenance approach, a pump and compressor upgrade is a good place to start.

Increasing volumes and speed

As demand on your facility increases, it’s imperative that your materials handling system can keep up. Bottlenecks not only cause stress and lag in other areas of your operation, but can also result in significant maintenance and material quality issues.

Increasing capacity requires an uptick in the volume of materials that can move through the pump and/or the speed at which materials can move. The latest generation screw pump has been redesigned for greater throughput and higher pressure by lengthening the barrel and screw, improving the seal, and changing the structure of the inlet hopper. This enables a >15% increase in volumetric efficiency, giving you the flexibility to increase throughput when needed.

Reducing energy demand

Cutting energy costs can make a significant difference to your bottom line – and have an impact on operational sustainability. Investing in the Best Available Technologies is an obvious way to cut OPEX and meet environmental targets.

With the improved seal on the new screw pump, greater energy savings are possible for higher-pressure applications (20 – 25 psi and higher) and power savings of up to 15% can be achieved in like-for-like applications. Reducing power consumption not only saves money and reduces your carbon footprint; it also means that your equipment isn’t working so hard, giving you better equipment life and reducing maintenance needs.

Increasing availability

Done well, maintenance is what keeps your system performing optimally. But if maintenance becomes a burden, it’s a sign something is not going to plan. A few things can make a real difference here:

• Spotting the early indications of a problem
• Acting at the right time
• Understanding the root cause

With these three things in play, you have a preventive maintenance strategy that will deliver long equipment life, high levels of availability, and low operating costs.

The screw pump and rotary vane compressor have been around for more than a hundred years, their robust design proven by the fact that some 100-year-old models are still in operation. In recent years, additional measures have been introduced to make maintenance even simpler and safer. For example, all new screw pumps are equipped with a 3-piece screw, which splits the pump screw into three sections – the centre section being the replaceable wear part. This eliminates the need to disconnect the coupling to perform maintenance, saving the bearings and seals from being exposed to a dusty, dirty plant environment. Now a screw change takes two technicians just 3 – 4 hours, about a third of the person hours of the old one-piece screw type.

Cutting costs

Increasing throughput, reducing energy consumption and being more proactive about maintenance are all strategic ways to improve cost-efficiency. Reducing the total cost of ownership (TCO) should be the driver for all process decisions, since that is a core tenet of achieving optimum process efficiency.

A quest to reduce both CAPEX and OPEX was behind the recent rotary vane compressor remodel. The new rotary vane compressor design has simplified castings, creating a cost saving that can be passed on to you. The cooling water jackets have also been redesigned, reducing weight and minimizing costs.

Because operation and maintenance practices are a big part of TCO, training is also important. A screw pump and rotary vane compressor can be shipped to your plant for hands-on learning opportunities that improve operator knowledge of performance and maintenance issues.

Pneumatic conveying partners

For more than a hundred years, the screw pump and rotary vane compressor have worked in partnership in pneumatic conveying applications. The screw pump works efficiently to push material from its gravity-fed hopper through the barrel into the discharge body, where the rotary vane compressor provides the required compressed air to convey the material through the transport line. Both machines are durable and easy to maintain, with the capability to be installed in any plant environment.

Standard features of the screw pump

• Cast iron and steel construction, with a cast iron base.
• Ball bearings support a pump screw at both ends for smooth, balanced operation.
• Critical parts that come into contact with material to be conveyed are made of hardened, wear-resistant material and special hard surfacing.
• Screw is coupled to the driving motor but can be v-belt driven.
• Easy, low-cost maintenance thanks to the 3-piece screw.
• Diameters from 150 mm – 350 mm with capacities up to 600 mtph depending on bulk density.
• Conveying air pressure range up to 35 psig (~2.4 Bar)
• Built to withstand material temperatures up to 400 °F (~200 °C) as standard.

Standard features of the rotary vane compressor

• Cast or Ductile iron cylinder allows for up to five re-bores
• Solid one-piece rotor and shaft can be re-slotted several times for different blade thicknesses
• Shaft and bearing design minimises drive losses
• Integral cooling water jacket
• Inlet/outlet configuration eliminates internal compression losses
• Mechanical seal for gas applications