Plant personnel often face a challenge when taking inventory reading of biomass material in a multi-story silo. On the other hand, a single-point measurement does not deliver a precise inventory reading because not only the level of material has to be measured, but also its volume. According to BinMaster, a company specializing in bin level indicator and control systems, when a bin measurement is off by just a small percentage, the error can prove quite expensive. Therefore, precise inventory management is an important step in cost analysis. When the costs of raw material and the related costs of inventory management shoot up, a reliable inventory management system (IMS) becomes an essential commodity to an organization’s fiscal bottom line.
Image Credit: Shutterstock/Roman Zaiets
3DLevelScanner and SmartBob
SmartBob and 3DLevelScanner are systems that act as perfect substitutes for traditional tape measure technique. The 3DLevelScanner is a non-contact device offered by BinMaster and is capable of measuring wood chips and similar types of biomass. It can even be used to determine flour, cement, sand, soy meal, limestone and distiller's grains, provided that the material measures a minimum of 12 lbs per cubic foot. This will facilitate the scanner to read it precisely. Solids tend to produce a considerable amount of dust. A dusty condition is a common phenomenon in almost every storage vessel and this can prove difficult for other technologies, such as ultrasound and radar, wherein the signal can get baffled and transmit an incorrect reading. On the other hand, the 3DLevelScanner overcomes this issue as its low-frequency signals enable it to pass through and ignore the dust.
Multiple Point Measurement
The scanner, which operates between 2 and 10 kHz, is integrated with a sensor that is based on acoustics. Though other sound-based systems function in a low frequency range, they tend to provide only a single-point of measurement. In contrast, the 3DLevelScanner calculates the time it takes for echoes to rebound off from surfaces and also determines the angle.
Figure 1. The 3DLevelScanner installed on a corrugated steel bin used for wood pellet storage.
The scanner maps the surface of the material and takes the peaks and valleys to provide a precise volume, besides the 3D representation. This way, one can view the material’s ‘cone up’, ‘cone down’, build-up at side walls, etc. The scanner is repeatable and reliable and performs well in dusty environment. Data is provided in average, minimum and maximum levels. The redundancy of the system is based on three self-cleaning transducers. Each transducer is covered with an aluminum alloy membrane that is enclosed in a material similar to Teflon.
Vibrating Rods
‘Point level’ products available from BinMaster will alert users when the bin is either full or empty. The company’s advanced vibrating rod type technology is designed for high temperatures. The rod, dubbed as Super High Temperature, includes a piezo system that is particularly designed for higher process temperatures of approximately 250°C. The durability of the Super High Temperature depends in part on a reinforced membrane, and also on an insulation tube on its piezo system. This tube protects the electronics from extreme heat. The probe and electronics are placed within an enclosure manufactured from IP66 and IP67 aluminum alloys for extra protection.
Figure 2. The scanner can be used on large diameter silos such as 105' and greater since it measures multiple points of the material surface.
SmartBob, also called as a yo-yo system, is used for inventory management as it features a sensor probe, which is joined to an air draft cable. The device is placed on the bin’s top and simply comes down until it touches the material. SmartBob’s sensor operates like an automatic measuring tape and eliminates the risk of climbing bins to take measurements. The sensor can be configured at pre-programmed intervals as per the requirements of the operator.
Figure 3. The user can view real-time data for multiple bins on a single screen using MultiVision software from an office.
Conclusion
Precise measurement can help in preventing a silo’s collapse. The 3DLevelScanner can aid operators avoid unnecessary damage to the silo and its immediate structures. In addition, constant monitoring under accurate situations can help trace inexplicable differences and aid in pursuing a follow-up inspection. The 3DLevelScanner has been successfully used in pellets and wood chips at a number of biomass plants. The wood applications can be very dusty, and the low frequency technology of the scanner penetrates dust reliably. In addition, depending on the moisture content, the pellets and chips may get stuck on the sides of the bin. Here, multiple-point mapping provides a significant advantage.
This information has been sourced, reviewed and adapted from materials provided by BinMaster.
For more information on this source, please visit BinMaster.