Benefits of installing a new centrifuge
Deciding when to replace plant and equipment is a dilemma that every business faces from time to time. As the UK agent for Flottweg, it’s a discussion that we regularly have with clients regarding their centrifuges, and there is no simple answer.
The expected operational lifespan is, of course, an important consideration. This is the figure that the accountants will use when valuing assets on the balance sheet each year and calculating depreciation costs. However, it is by no means the only factor. Sometimes, a piece of equipment will continue to provide reliable service far longer than expected. We see it in our day to day lives, for example with those lucky people who drive cars that have covered hundreds of thousands of miles and continue to be reliable.
Yet when a business relies on a piece of equipment like a centrifuge in order to operate, it would be a mistake to make any assumptions. The expected lifespan is affected by a whole host of influences including the operating conditions, maintenance and servicing, type of use and so on. A breakdown, preventable or otherwise, can have a huge impact on productivity, effectively grinding an operation to a halt, with a knock-on effect that hits customer satisfaction and the business’s profitability.
But even if an old centrifuge is still operating as it should, it can still make sense to replace it if the new model will deliver significant benefits and savings. It’s a little like replacing that perfectly running 250,000 mile car with a new one that delivers better fuel economy, lower emissions and a superior driving experience.
Quantifying the benefit
That brings us full circle to the question of when and whether the benefits of installing a new centrifuge outweigh the capital expenditure cost. Flottweg recently carried out a study on this very question in cooperation with Lower Neckar Wastewater Association in Germany.
This wastewater treatment plant has been operating for decades, and uses two Flottweg Z4D centrifuges that were installed back in 1997. After 22 years of service, it was time to assess some upgrade options, so in April, Flottweg carried out a comparison test using the latest Xelletor model.
Using the newer technology yielded immediate and impressive results. Dry matter output showed an increase of two percent, which led to a ten percent reduction in disposal costs. At the same time, running costs were also significantly lower, as the newer centrifuge operates more efficiently. It uses five fewer kilograms of polymer per ton of material processed. As well as the financial savings, this also delivers green sustainability benefits.
Reaping the rewards
When the study was complete, it was calculated that the new centrifuge would pay for itself in just two and a half years. There’s no reason to doubt that the Xelletor will provide the same long service as the Z4D that came before it, but even if it only had half the lifespan, the savings over 10-12 years would be astronomical.