Scrubber Inspections with Zenith - Covanta

SAFETY

Zenith prevented the need for scaffolding and allowed inspectors to stay out of confined space.

Time

Requiring only minutes to set up, Zenith saves not only in preparation time but also inspection time.

savings

Since Zenith does not require traditional confined space entry or scaffolding, many costs were saved during inspection.

Customer Needs

Covanta was seeking a safer and more cost efficient alternative for required scrubber inspections that take place at their Waste-to-Energy facilities. These modern facilities are designed to convert the waste that remains after recycling into electricity for homes and businesses or for export to industries. Waste-to-Energy is a means of disposal that reduces greenhouse gases, particularly methane, by eliminating emissions from landfills.

The waste is first burned in a boiler which creates flue gas. This gas then goes into a scrubber which is an open vessel. Chemicals get mixed with the flue gas until solid pellets form, which then go from the scrubber and into the baghouse where a bag catches the pellets. The remaining clean gas goes out the stack. To learn more about the process, watch this video.

Covanta wanted to use Zenith for mainly two reasons: Zenith could be used during the years in between mandatory inspections to see if any damage has accrued or accelerated, and in turn, this would lead to a mass savings in scaffolding alone which can cost upwards of $50,000, compared to a Zenith inspection which is a tenth of the cost.

Our Solution

Interactive Aerial’s Inspection Service team completed the scrubber inspections with Zenith. Utilizing many advanced systems and safety features, Zenith allowed for a safe and fast inspection of the confined assets. The unit used its stabilized camera capable of capturing 4K video and 18MP photos with a 30x optical zoom. Hanging from a cable and free spinning bearing allows the inspection unit to have unlimited rotation, which enables the operator to see any spot needed inside the scrubbers.

Covanta’s scrubbers are constructed with a top access point that is narrower than the Zenith body. To work around this problem, one inspector descended down to a side access hatch while the other inspector lowered a weight down on the Winch’s cable. Using the Zenith retrieval hook, the inspector was able to safely grab the cable without breaking the plane for confined space, attach Zenith, and then steadily place Zenith into the scrubber through the side hatch. Once Zenith was finished running automation to capture 100% of the asset, the inspectors used the same process (as shown in configuration 2) to remove Zenith and safely spool up the cable.

The results

How were the scrubbers looking on the inside? Were there any noticeable defects that could be identified that demanded immediate attention? Did the data from Zenith provide enough for routine use in preventative maintenance inspections? Zenith was able to provide these results and more, establishing a safer and more cost efficient method tocarry out the inspections.

Covanta had two plants in two different states that were inspected by Zenith and the IA Inspection Service team all in a matter of three business days. When typically costing hundreds of thousands of dollars for full sand blasting, scaffolding and more, Zenith was able to complete the inspections for less than a tenth of the cost and in far less time.

Covanta has determined that Zenith and inspection robotics are a viable alternative to traditional confined space entry. Tools like Zenith are saving them time, money and the safety of their employees.