UK recycling rates have hit a wall and, in some areas, they are in reverse as local authorities switch to incineration for municipal waste, even if it has been sorted at the kerbside.
This of course shortcuts the well-established waste management hierarchy, skipping directly to recovery. China’s decision to ban the import of recycled waste has not helped matters, signalling a clear requirement for a stronger home-grown processing sector.
But saving money, especially for hard-pressed council budgets, is also a major factor – and in an industry where margins have always been challenging, it is not surprising.
For some MRFs, productivity issues due to stoppages are a significant problem and addressing them could make a real difference to overall profitability. Some 50% of the jobs attend by Middleton Engineering – either to repair conveyors and machinery or restore operational performance – are directly attributable to misuse, neglect and poor maintenance.
Allowing oversize materials into the waste flow, which invariably causes it to jam, or to operate machinery until it breaks, are fairly common. We have seen beer kegs jammed under gates and all sorts. Indeed, some sites experience almost daily stoppages, with one hour in every eight-hour shift lost and operators idle, while systems are isolated and repaired.
For a MRF processing 20 tonnes a day of waste, that could be 2.5 tonnes of lost production or 650 tonnes a year. Factor in the emergency repair costs plus time delays, and the business model starts to look fragile. Few businesses can operate successfully under such conditions.
Modern MRFs are designed and built for tough working environments, and should provide operators with a foolproof and efficient solution for receiving, sorting and separating waste, before baling it up and shipping it on to reprocessors.
But exceeding the original design parameters of the system will inevitably lead to premature wear and failure as components are overloaded. If you are building new or upgrading an existing facility, some element of future-proofing to account for increased throughput and higher volumes will avoid headaches later.
Contamination is an area that needs constant vigilance. It can occur simply between storage bays where dividing walls are not high enough. Adding guard rails to the top of dividing walls is a simple, low-cost solution.
But it really pays if an element of manual pre-sorting to remove oversize objects is employed rather than throwing everything on to the conveyor, irrespective of size. Hand sorting of large objects such as crates, car wheels and even fridges is essential to reduce the number of jams and stoppages.
A more insidious threat is parcel tape and polythene sheeting, which gets caught and wound around shafts and rollers. Cutting this off quickly before it can add extra strain to other components and bring the system to a halt also needs vigilance. Dirt and debris likewise should be kept at bay.
None of these should be difficult to implement, but a high staff turnover at MRFs can make it challenging.
Having an on-site maintenance engineer, with responsibility to implement and manage preventative maintenance programmes and ensure that operators are trained to follow procedures, will certainly help.
The same person will be able to carry out essential servicing, liaise with suppliers to purchase and stock spare parts and even recommend appropriate modifications and improvements to support productivity and safety.
But if a MRF operator does not have this luxury, there are still things that can be done to ensure trouble-free operation. Combine this with regular servicing and the experience should be better performance and fewer costly surprises throughout the year. Simple measures work best:
- A wall chart with daily and weekly checklists is useful at the start or end of each shift, while reinforcing safer working and minimising machine abuse.
- Rusty chains are a typical failure point leading to plant breakdown. They may not have been checked for months, so a visual reminder to inspect and lubricate at specific intervals will pay dividends.
- Regular cleaning regimes to lubricate chains, bearings and drive parts, and inspect safety switches and guard rails, should all be included. This way you can minimise disruptions and maximise productivity, scheduling planned maintenance shutdowns to times that suit your operation.
A little bit of TLC at a MRF could make all the difference to boosting productivity in a hard-pressed sector, and it has a positive impact on health and safety too.
Richard Turner is service coordinator at Middleton Engineering