The waste-to-energy industry is helping to solve the growing problem of what to do with our waste materials. Worldwide, revenues from the industry at the end of 2012 accounted for US$17 billion and are expected to reach US$28 billion by 2016, according to a report by global growth consulting firm, Frost & Sullivan;
Waste management companies have stepped up their involvement in building waste-to-energy processing units – moving from traditional waste handling to integrated plants combining waste handling and power generation into a single-line process. Building such plants requires considerable investment, a secure supply of waste materials and extensive time to plan and execute. These facilities present unique risk management challenges that must be managed to guarantee safety, reputation and business continuity.
To ensure a waste-to-energy facility’s operation seven days a week, 365 days a year, two common property risk management challenges must be considered: fire and machinery breakdowns.
Preventing equipment breakdowns
The combination of power generation and waste management fuses together a variety of automated and complex operations. At its core, the introduction of power-generating equipment brings elements uncommon to the traditional waste management industry. While the capability of this equipment offers a robust revenue stream, ensuring that the machinery performs as expected and without interruption requires constant monitoring by skilled technicians.
A main factor in preventing breakdowns is mitigating the human element risk. The use of complex power-generating equipment requires highly skilled and trained operators. At a time when businesses are tasked with operating under very lean circumstances, they must invest in skilled machine operators to ensure the continuity of operations. Experience has shown that trained operators can avert an incident and lessen the impact on operations.
Another way to prevent breakdowns is to ensure machinery is consistently maintained and operating optimally. This includes adhering to a strict maintenance schedule to minimize potential outages.
When large volumes of waste are handled, the risk of fire is ever present, making automatic fire protection a necessity. In waste-to-energy, automation into a single-line process has brought additional risk management issues. The waste handling and control systems are particularly vulnerable.
If a fire starts and goes unnoticed, there is a high probability that essential equipment will be damaged. If cranes are damaged, for instance, waste will not be transported to the furnaces for burning. Furthermore, bunkers at waste-to-energy facilities are often equipped with water cannons to combat fire; but during a fire, heat in the bunkers can make it impossible for personnel to reach the cannons. In extreme circumstances, the structural integrity of a bunker will be jeopardized.
Automated conveyor systems are also extremely vulnerable to fire. These conveyor systems are equipped with rubber belts that, if involved in a fire, will serve as fuel for fire to engulf the system and surrounding materials. If the conveyors then collapse, there may be no other way to move waste or remove ash from the furnace. Both of these scenarios could shut down operations. Manual firefighting is often challenging because the conveyors may be elevated or in confined spaces. Therefore, installing automatic sprinkler systems above conveyors and interlocking conveyors to shut down when the systems alarm will help mitigate this hazard.
In some facilities, waste is prepared as fuel by using a system of shredders—increasing the risk of localized fires. This may be exacerbated by pressurized cans containing propellants in the waste stream (e.g., flammable aerosols). Isolating these areas and ensuring that they are adequately protected with automatic sprinklers can also diminish the fire hazard.
Equipment breakdowns and fire at waste-to-energy facilities have the potential not only to cause property damage and business interruption, but also to garner media scrutiny and affect business reputation. Furthermore, the significant investment involved in these facilities translates to a keen focus on delivering results to investors. Consequently, a robust process around business resilience is needed to minimize the frequency and severity of operational incidents, to maintain focus and reassure neighbors and investors.
Mitigate the Equipment breakdown
• Establish and invest in maintenance routines, beginning with the operationally critical and more costly items, such as turbines, where a loss of generation capacity would have a direct impact on the facility’s financial performance.
• Install fixed, automatic sprinkler protection over critical conveyors or develop a contingency plan for the movement of waste materials in the event of a conveyor loss.
• Shut down the conveyor system in the event of a fire to stop the fire from spreading.
Fuel preparation (shredding)
• Use solid construction to isolate shredders.
• Install fixed, automatic fire protection over shredders.
• Establish a prefire plan designed to help combat site-specific fires and to coordinate fire protection equipment and personnel resources at the site.
• Conduct annual fire drills.
• Install fixed, automatic sprinkler protection at roof level, fed from an adequate water supply.
• Provide manual or automatic fixed monitor nozzles for manual firefighting at a sufficient pressure to ensure water jets reach the whole waste pile.
• Ensure that hired contractors have the correct level of training and supervision to understand the equipment, procedures and potential hazards at the site.
• Provide consistent training of operators to make sure they are familiar with new or updated equipment.
Lee Kenny is an FM Global senior engineering technical specialist.
This article first appeared in Reason Magazine Issue 1: 2015.