Tube Bundle Cleaning Gets Automated

Showcasing the benefits of safety and production in cleaning ethanol evaporators. This contributed article appears in the June print issue of Ethanol Producer Magazine.
By Terry Gromes Jr. | May 17, 2017

One doesn’t have to look far to see that automation is an everyday occurrence in our lives. Your Keurig automatically brews exactly 8 ounces of coffee to start the day. Canary automatically activates your home-security system once you walk out the door. Pandora automatically picks your song of choice as you fight through rush hour. Your Ford sedan automatically parks itself once you arrive at work. If your java and music can be successfully automated to your liking, can your tools at the workplace function in the same manner?

As the importance of safety and production in the ethanol industry is being recognized, the need for automated tooling for cleaning is in high demand. The current process of cleaning ethanol evaporators, developed around high-pressure water, relies on the worker to clean by hand. This creates an extreme environment for the worker who is holding the hose containing high-pressure water in his hands, and is the sole source of delivering this high-pressure water from one tube to another. Not only is he constantly exposed to high-pressure water and hazardous working conditions, he is faced with unavoidable worker fatigue accumulated through manual labor over a 12-hour shift, resulting in inconsistent cleaning.

Replacing the hands-on worker with a hands-free mechanized tool designed specifically for tube bundle cleaning solves these problems. Standard solutions include a hose feeding device paired with a navigating apparatus (commonly referred to as an indexer or positioner) to aid cleaning tube to tube. With these systems, safety is achieved by removing the worker from high-pressure water exposure. Worker efficiency is multiplied due to the hose feeding devices feeding multiple lances at once. With the former hands-on worker now operating a mechanized tool, a single worker can now double or triple his work production. Finally, the unavoidable physical fatigue of the worker over a 12-hour shift is replaced by the consistent feed of the hose feeding device, providing cleaning consistency throughout the entire bundle.

Mechanized hands-free tooling successfully provides a safe and efficient solution to the generalized water-blasting industry by replacing a manual worker’s inconsistent physical performance with controlled mechanized consistency and by removing the worker from hazardous cleaning conditions.  When applied to the ethanol industry, however, multiple challenges arise in this attempt to achieve automation and production in the same scenario. Some of those challenges include:

• Vertical orientation of ethanol evaporators and the limited enclosed work area is always a challenge in the ethanol industry due to limited means of transport and the small working area outside of the blast zone.

• Twenty-four inch man-ways restrict the sizes of entry, thus requiring tools to fit within the confined walls and to be lightweight for transport and setup.

• Navigation of a standard indexing system which travels on the X/Y axis inhibits full bundle coverage, dictated by the axial lengths and the location of the lance guide positioners. Consequently, the tool must be relocated several times within the evaporator, with the tubes along the walls ultimately still being cleaned by hand.

• The single angle view of the blast zone, the direct area on the tube sheet where the cleaning is performed is another obstacle. Within a confined entry clean of an ethanol evaporator, a single line-of-sight is the only available view for the operator through the man-way, limiting his view of the tool to one angle and not providing multiple visual opportunities.

• Steam, lighting and debris are elements that hinder the line-of-sight over the cleaning shift, many of which are unavoidable. The steam, which is released by the high-pressure water, has only the man-way for escape. With more steam being created than escaping, it creates a visual mask over the mechanized tooling, resulting in minimal sight when navigating from tube to tube to clean.

Combining the full array of modern automation tools with hands-free mechanized tooling provides multiple solutions to these restrictions when cleaning ethanol evaporators.  Using a touch-screen tablet, for example, serves as a command surface to control the system. A standard Bluetooth wireless connection allows the operator to control the tool installed within the confined entry while being located outside the man-way. It removes the operator from the hazardous working area known as the blast zone and eliminates cables and hoses that can hinder movement, limiting the risk of slips, trips and falls. The on/off control of the high-pressure water can be controlled at the tablet, eliminating an additional worker that would typically control this feature.

Terydon Inc. has paired safety objectives with productivity goals in its Smart Indexing, automated tooling, which allows the operator to automatically navigate from tube to tube by a single click of the button. Smart Indexing provides a consistent navigation that, much like the feed rate of the hoses, is reliable and accurate over the course of the cleaning process. It addresses the issues of navigating with steam, low lighting and other ailments affecting the operator’s line-of-sight. 

The addition of a patent-pending radial arm in Terydon’s 3A Indexing System facilitates navigating to all the tubes along the walls, avoiding hand cleaning. All the tubes in an ethanol evaporator can be accessed. Data collection and recall features also are available to help maximize efficiency by remembering feed rates, time to navigate and percentage of clean.

Author: Terry Gromes Jr.
Product Support, Terydon Inc.