Getting ready for the festive plant shutdown

For those industries that shut down over the Christmas and New Year period, planning will now be well under way for any shutdown maintenance required. As an essential utility that rarely goes offline, this shutdown period presents the ideal time to schedule in compressed air system maintenance and upgrades.

Like gas, electricity and water, compressed air is an essential utility required day-in and day-out by many areas of industry. It can therefore be quite difficult (especially if a backup system does not exist) to schedule in time for larger maintenance tasks and to undergo system upgrades. Here, the festive shutdown period offers the perfect opportunity.

Make the most of the longer shutdown

Some typical compressed air system maintenance tasks that require a longer shutdown period include replacing motor bearings; removing and cleaning coolers; and performing oil/water separator cleaning and replacement.

With the festive period also falling towards the beginning of summer, it also makes sense to perform a number of routine maintenance tasks that will ensure your compressed air system is ready to handle the hot summer days ahead, such as changing the oil and the inlet filter to checking the fluid system, belts and couplings.

One of the most important things that can be done during the summer months is keeping coolers clean. Dirty coolers can cause a number of problems such as contributing to compressors running hot. Elevated running temperatures increase oil carry-over from the compressor, which will eventually lead to a low oil level and ultimately a compressor shutdown. Depending on the state of the coolers, high pressure cleaning or ultrasonic cleaning may be advised.

A long shutdown may also be the ideal opportunity to fix identified air leaks. Unfortunately all compressed air systems will have compressed air leaks. Statistics suggest that the average leak rate is 25% with some plants losing as much as 80% of their compressed air through leaks. But, what is the cost of leaks? As an example, a compressor that operates at 6 bar will consume an additional 0.39 kWh for a one 1 mm hole. This equates to an annual cost of $512, assuming the system has a power cost of 15 cents per kWh for this single leak alone. The good news is that detecting and fixing compressed air leaks has an overall energy savings potential of 6-10%.

Detecting and fixing compressed air leaks has an overall energy savings potential of 6-10%.

Upgrade and optimise compressed air systems

Beyond maintenance, if system upgrades and optimisation are being considered, then the shutdown period also presents a great opportunity to implement them. Below are a few areas to consider.

Implement a bypass line

A bypass line makes it possible to continue to transport compressed air through the system while, for example, line filtration is maintained. However, a bypass line can often be overlooked when a compressed air system is installed. Installing a bypass line would therefore mean that any future work required on line filtration will not have to wait until longer shutdown periods. The festive shutdown is the perfect opportunity to install a bypass line if one doesn’t already exist.

Invest in an air-main charging system

Whether it’s overnight, over the weekend, or for an extended shutdown period such as the festive season, when compressors are shut down, there is a risk of overloading the air treatment equipment and contaminating the compressed air system when the compressors are restarted. These unwanted outcomes can be easily and cost-effectively avoided by simply integrating an air-main charging system. Installed in the compressor station just downstream from the last air treatment component, the air-main charging system ensures that the compressed air system remains pressurised even after the compressors have been shut down, thereby safeguarding compressed air quality.

Planning ahead for optimal outcomes

A little planning now will go a long way in terms of making the most of the upcoming festive shutdown period. It’s a good time to consult a compressed air provider and to discuss together what maintenance jobs need to be conducted and any upgrade plans being considered.