EU regulation on ozone depleting substances prohibits the use of the low temperature refrigerant R22 as a top-up fluid for maintenance from 2010, and with a complete ban set to take effect from 2015, companies need to consider alternatives and how they will manage the transition.
There are generally two main uses for R22 – in air conditioning systems and refrigeration units. The biggest users tend to be supermarkets, then the manufacturing sector, in particular the food and drink industry and the chemical sector. But, every organisation has a responsibility to eliminate the use of R22 from their equipment, from office and public sector buildings to industrial plants.
A number of options
For plant managers and building engineers there are a number of options available when looking to eliminate R22 from processes. The first is to replace the whole plant or process that currently uses R22. Complete plant replacement provides an opportunity for the company to improve its energy efficiency, ensure that the new equipment is designed for its current cooling requirements, which may have changed, and install the latest and most reliable technology. However, a project of this scale presents many challenges, such as minimising disruption to ongoing operations and smoothly integrating the new plant. Once the new equipment is installed, there is also likely to be a ‘bedding in’ period to check that it is all working correctly.
There is a solution available to assist organisations taking the route of total plant replacement and changing an R22 system can be made a lot less problematic with the use of temporary solutions, which can help minimise disruption and costly downtime. Temporary temperature control equipment such as water chillers and air handling units can take over from permanent plant and machinery. Such equipment can be used for both process cooling and refrigerating stored produce and can be sized according to exact individual requirements.
The second option for companies to phase out R22 is to modify equipment to use a new refrigerant. Opting for modification, which involves flushing out the existing refrigerant and replacing it with an acceptable substance, such as R407c or R404a, is quicker to implement than installing new equipment and has lower capital costs. However it isn’t just as straight forward as removing the R22 from the system and may also involve upgrading some components such as expansion valves, filters and oil so that the equipment is compatible with the new refrigerant.
As with the first option, there is likely to be a trialling period once the system has been restarted. This is essential following modification as the efficiency of the equipment could be worse and there could be leaks and reliability problems. As there will still be some level of downtime and disruption caused by the process being temporarily shut down to allow the modification work to happen, again temporary solutions such as chillers can be used to keep systems operating.
Some companies are currently taking the third option and have been avoiding the issue of either maintenance or installation of new refrigeration systems, opting instead to improve containment and running the equipment until the refrigerant runs out. This does not remove the need to plan now for future conversion or complete replacement. In addition the availability of reclaimed R22, which is acceptable to use until the end of 2014, is decreasing as producers scale down their production to avoid holding surplus stock. The result is likely to be an increase in price as well.
An effective solution
Those responsible for operations and production often prefer temporary chillers to be powered by a temporary generator so that they can be confident there will be no disruption to the plant while any replacement or renovation work is being carried out. Placing a silenced canopied generator alongside the temporary temperature control unit allows the most convenient and effective positioning of the machinery without the added issue of having to locate to mains power supply and establish an effective connection.
Planning is key to a successful transition and a site visit with experienced engineers is essential. When looking into any kind of temporary power arrangement, it is important to identify the individual requirements of a company’s operations and not to compromise on energy efficiency. With a generator, as with any other machine providing power to a process (such as a compressor) output needs to meet demand for it to work efficiently. Using a generator that is over-sized for the amount of energy required and operating under capacity can cause just as many problems as a machine that isn’t producing enough power.
It is also necessary to consider the type of load demand, such as low power loads, leading power loads and Total Harmonic Distortion (THD). If not properly understood, these can have a detrimental effect on equipment such as switchgear, cabling and alternators.
Other important considerations include the specification of cabling and pipework – which carry the load to the process line – fuel supply and compliance with the G59 regulations, which cover the use of generating plant running in parallel with the grid. Additional fuel tanks can be provided to allow the generators to run for longer periods than are possible using only the generator’s built-in tank. For added peace of mind, a fuel management service can also be used to deliver top-up fuel to site before equipment runs dry.
The old saying ‘time costs money’ is never truer than in process situations, so taking steps to protect productivity – and the bottom line – should be standard practice when planning for any kind of maintenance work. The right generator set-up can make a big contribution to that planning, whether for ongoing maintenance or emergency back-up.
With the government putting increasing pressure on the UK’s businesses to become more environmentally conscious, engineers need to consider ways to adopt new processes without disrupting production. New legislation, such as the banning of R22, will continue to pose such challenges, but by using temporary equipment to best effect, plant equipment can be maintained, upgraded or modified with minimum downtime.