Faced with evolving legislation, ever-changing market forces and mounting environmental pressures, the life of a biomass operator is rarely straightforward. But with challenge, often comes opportunity, believes Gary Moore, director of global business development at Untha Shredding Technology. He has consulted with firms on the ‘front line’ to hear where the greatest complexities currently lie, before exploring, more importantly, how to overcome them...
1. Dust and the disposal of it
Wood processing is widely considered an inherently dusty operation, especially if using high speed processing equipment for a grade C operation. Generally speaking, the greater the level of dust, the larger the risk of fire or explosion in the event of a mechanical spark.
Regular cleansing of the biomass production plant is therefore recommended to keep dust levels to a minimum. In-built fire suppression technology with heat detectors and extinguishing nozzles should also be sought within the wood shredder, so that a fire can be mitigated before it breaks out.
Dust levels can be further reduced, by design. The target speed for a modern wood shredder should be no higher than 60rpm. Such slower speed equipment – with high torque to maintain throughput performance – will naturally generate less dust and lower fines (as low as 5%). At the same time as avoiding costly disposal fees, the operator should then be able to yield up to 20% more saleable biomass material per tonne.
2. Operator wellbeing
Linked directly to point 1, biomass operators are becoming increasingly aware of their duty of care to protect employees’ on-site wellbeing. Noise – as well as airborne dust – pollution, is difficult to manage, especially when running high speed, diesel-driven machinery. Given prolonged exposure to excessive noise can have a debilitating effect on individuals’ hearing, noise reduction measures should be sought where possible.
Of course, hearing protection can be worn, but optimum conditions involve machinery that runs below the first action point of 80dB(A), i.e. when ear defenders are not required.
A quieter biomass production line will keep plant neighbours and planning departments happy too, especially if extended operating hours or facility expansion is sought.
3. New fire plan limits
Updates to fire prevention plan guidance last year, were understandably required to help minimise the outbreak and spread of fire, on sites with combustible waste materials such as biomass.
But maximum pile sizes are particularly challenging for busy, fast-paced operators. Limits vary according to material specification, with 750 cubic metres of loose >150mm wood permitted for instance, compared to only 300 cubic metres of <30mm wood.
Operational consistency – without any unexpected downtime or stoppages – is therefore crucial so that firms can try to manage capacity and continuity. Easy to maintain, robust technologies with foreign object protection should help in this respect.
4. Achieving particle homogeneity
The production of a defined, high quality, on-specification fuel is crucial for any biomass operator. Numerous technologies exist to help achieve such homogenous output fractions, but in the face of market volatility and economic pressures, many producers are understandably reluctant to invest in multiple system components such as screens.
This capital outlay can be avoided by procuring machinery that consistently manufactures on-spec biomass in a single step. Reduced energy, wear and maintenance costs will also accelerate the operator’s machine payback period by up to 50%.
5. Machinery running costs
Irrespective of the initial price tag of a biomass shredding system, the true financial impact of the investment is largely affected by the whole life running costs of the machine. High wear parts that require frequent replacement will soon escalate the true ‘price’ of the technology, for instance, and costly repairs and/or unexpected downtime will be disruptive and financially burdensome.
Robust, low/easy maintenance technology with long service intervals and efficient energy consumption will help minimise whole life running costs by up to 70%.
6. Product contamination
The contents of waste streams can never be guaranteed, so some product contamination is perhaps to be expected. However, the presence of foreign objects can harm both the resulting biomass quality and the processing technology itself.
The shredding system must therefore have built-in resistance to unshreddables, ideally with a robust cutting chamber, plus an auto stop function that prevents machine damage and enables the foreign object to be quickly and safely discharged.
7. Finding the right people
Businesses are nothing without their people, but finding driven, committed colleagues who care about company values, operational health and safety, and the UK’s environmental agenda, is not always easy.
The biomass industry routinely experiences ups and downs, and the extra ‘graft’ of colleagues often goes a long way to ‘keeping the dream alive’. Continued communication, development and celebration of achievements, will help retain hard working colleagues and attract new candidates too.
A special thanks to Lee McGlone, operations manager at Crapper & Sons, for his input into this feature.