Learn how keeping your RTO clean of unwanted residue can improve efficiency.
Regenerative Thermal Oxidizers (RTO) are used to destroy harmful emissions produced by certain manufacturing plants. RTOs heat volatile organic compounds (VOC) present in exhaust streams to high temperatures, leading to combustion. This process is called thermal oxidation.
While many volatile compounds are safely destroyed using this method, a benign residue can build up in the combustion chamber and media bed during operation. Residue entering the unit alongside exhaust streams can become stuck to the interior walls of the equipment and affect the machine’s efficiency.
In some cases, the formulation of unwanted residue is the result of the combustion process itself and cannot be avoided. Regardless of the cause, the dirt and grim inside RTO components must be properly maintained and cleaned to keep the unit running smoothly.
RTO Media Cleaning Methods
The efficiency of the unit is crucial in meeting EPA regulations and manufacturing objectives. Built-up residue can decrease airflow and lead to higher fuel requirements. In addition, valve seals and other intricate components can become damaged by excessive layers of unwanted particulates. Cleaning the media and combustion chambers can improve efficiency and increase the life of your unit. Therefore, maintenance of the equipment must be carried out at regular intervals.
There are two methods commonly used for cleaning an RTO system: bake-out and wash-down. The specific RTO and the type of media installed in the unit may affect which method you use. If you notice unusual drops or increases in pressure, fan speed, and fuel consumption, the unit may be in need of a bake-out or wash-down.
The bake-out method works in the same way as a self-cleaning oven. The media bed is heated to roughly 850 degrees Fahrenheit, causing any residue caught in the chamber to be incinerated. Each section of the unit is heated in succession to ensure all areas of the machine are thoroughly cleaned. Typically, the most affected areas in an RTO are the lower and cold-face sections.
Once the bake-out has been completed, the unit can be reconnected and operated as normal. In some cases, the operation can be performed during production. Bake-outs are typically carried out manually; however, the unit can be programmed to automatically conduct a cleaning on a regular basis.
The wash-down method uses water or solvent streams at low pressures to remove residue directly from the media bed. After the equipment has been cleaned, the media must be completely dry before the unit can be operated. Due to the fact that this method is more hands-on and requires drying time, the entire process is typically longer than that of a bake-out. Depending on the material and design of the media bed, multiple wash-downs may cause damage over time. Structured block designs are typically less prone to wash-down damage than randomly packed ceramic media.
Taking pollution control units offline for regular cleans can halt production and impact overall manufacturing costs. However, cleaning residue from the interior chambers can increase the health and longevity of the unit, which may lead to increased productivity. It’s worth noting that the continual application of high temperatures and washouts may ultimately wear down the media bed. Therefore, regardless of which cleaning method is used, the media may need replacing over time.