C^4’s Patented Adjustable Riffler and Fuel/Air Balancing
What is it?
Coal travels from the pulverizers to one or two boilers with the help of several fans. Each pipe containing this coal/air mixture will split into 2 or more pipes at various junctions (the number of which depends on the particular plant). It is of vital importance that the coal/air mixture is distributed evenly in the split, with the exact same amount of both coal and air in each pipe from a specific pulverizer. Therefore a riffler (or a number of rifflers), meant to divide the coal/air mixture into equal parts and guide it into the appropriate direction, is located at every split.
Generally, rifflers are triangular-shaped with channels on each side. The channels direct the coal and air; so the distribution is controlled by the number of channels on each side.
Conventional, non-adjustable rifflers are always evenly split (with the same number of channels on each side). The coal flow and airflow are expected to divide equally with the help of the fixed plate riffler. A standard riffler is shown below. The distance between divider segments on a standard riffler is 1 inch and has an equal number of segments on each side.
Coal travels from the pulverizers to one or two boilers with the help of several fans. Each pipe containing this coal/air mixture will split into 2 or more pipes at various junctions (the number of which depends on the particular plant). It is of vital importance that the coal/air mixture is distributed evenly in the split, with the exact same amount of both coal and air in each pipe from a specific pulverizer. Therefore a riffler (or a number of rifflers), meant to divide the coal/air mixture into equal parts and guide it into the appropriate direction, is located at every split.
Generally, rifflers are triangular-shaped with channels on each side. The channels direct the coal and air; so the distribution is controlled by the number of channels on each side.
Conventional, non-adjustable rifflers are always evenly split (with the same number of channels on each side). The coal flow and airflow are expected to divide equally with the help of the fixed plate riffler. A standard riffler is shown below. The distance between divider segments on a standard riffler is 1 inch and has an equal number of segments on each side.
What makes the adjustable riffler different from others?
In combination with the adjustable riffler section, we offer the ability to correct known measured imbalances with options for ratio splitting. The adjustable section, to be located in the heaviest coal flow area, is 1/3 to 1/2 of the riffler housing area. This leaves options for solutions regarding air balancing, basing independent airflow adjustments on the low coal flow areas. Normally, the fixed sections are installed to aid in correcting airflow differences. The adjustable section is installed directly above the high coal flow area that clearly shows high wear in the standard riffler section.
In support of the fixed selection, the unique adjustable riffler has a translatable plate and therefore the channels on either side can be adjusted larger or smaller, depending on the need. This allows for more precise manipulation of the flow in either direction.
Another major critical benefit of this riffler is that there is no increase in pressure loss to the overall system as a result of flow manipulation. This is because the coal flow and airflow are adjusted independently of one another, and the total area open to the coal flow remains unchanged.
How it works:
The first step to properly using the unique adjustable riffler is to determine the area through which the heaviest coal flow travels. As a result of the consistency of coal combined with the method with which it’s mobilized, the bulk of the coal tends to migrate towards one general area in the pipe junction. This area of heavy coal flow can be identified by surveying the former used rifflers. The area of the old rifflers with the most wear damage will be the area of the pipe with the heaviest coal flow.
The adjustable riffler must always be located in the area determined to have the heaviest coal flow. This will result in the adjustment of the channels having the most significant impact. The next step is to verify the data with instrumentation to determine what adjustments are needed. Since the adjustable riffler can be moved in small increments, a precise balance of equal coal flow in each direction is achievable.
Once the majority of the coal flow is precisely distributed using the unique adjustable riffler, the airflow should be adjusted as well. This is accomplished with a somewhat traditional method using non-adjustable riffler sections based on the need. Again using instrumentation to determine where needed, these are strategically placed on either or both sides of the adjustable riffler.
Basically, the adjustable riffler controls the coal flow while the non-adjustable riffler sections balance the airflow.
Once the airflow has been balanced, instrumentation is used one last time to ensure both the coal and airflow are distributed precisely. Any last tweakings can be done at this time.
For more information regarding the unique adjustable riffler, including assessment of your fuel delivery problems, impact to efficiency and emissions, and potential purchase information, refer to the “Contact Us” tab above.