Super cement producers care about people, products, and profit. 3D scanners, laser, and radar technologies ensure accurate monitoring of product levels.
No manufacturer wants to risk a bad batch due to missing materials. That's where sensors come in. Cement manufacturers find non-contact level sensors attractive for several reasons:
- Nothing comes in contact with material
- There’s no risk of equipment interfering with the process, or rogue parts breaking off or getting stuck in equipment
Continuous level measurements optimize inventory and prevent silos from running empty
The sensor best suited to a particular application is determined by several factors, including the material(s) being measured, dust in the environment, size of the silo, and desired inventory accuracy. Communications options for retrieving the required data also varies, along with sensor pricing and mounting, wiring, and installation costs.
BinMaster's 3DLevelScanner is generally chosen based on budget, vessel size, desired accuracy, and the desire for 3D bin visualization.
See Through Silo Walls
Cement producers can get the equivalent of x-ray vision using a 3DLevelScanner. With dust-penetrating technology, 3D scanners visualize and digitize the topography of bulk material inside a silo. A 3D scanner is mounted at the top of a silo and at an optimal location recommended for superior surface coverage, ensuring the scanner can best "see" the material surface.
Techno-Speak
The 3DLevelScanner sends acoustic pulses that sound like chirping crickets to the material surface in a 15°, 30°, or 70° beam angle, depending on the model. It then measures and maps the material surface at multiple points to detect uneven topography.
Distance is calculated using advanced algorithms that convert the difference between the time the echo was sent and received to a distance. Data is sent via 4-20 mA or RS-485 output to software or an HMI/PLC. The scanner's included MultiVision software records the data and calculates level, volume, and mass, in which it creates an optional 3D visual of bin contents.
Customize Results in Your Bin
The 3DLevelScanner is the only level sensor that measures multiple points on the material surface to account for irregular topography. The scanner provides precise volume measurement within 1% to 3% of the total stored volume. For cement plants, it offers the added benefit of detecting cone-up, cone-down, or sidewall buildup.
Scanner Data Goes to MultiVision Software
MultiVision creates actionable reports from scanner data. It easily tackles cement operations with numerous silos or various locations that want to monitor inventory throughout the operation.
Avoid installing 3D scanners where there is excessive noise that may interfere with the acoustic technology. They also are not recommended for very narrow bins that have corrugation. If there are excessive internal structures that may interfere with operation, a neck extension or alternative sensor technology will need to be used. Due to its robustness, there is no loop power option.
Non-Contact Radar Zaps a Single Point
BinMaster’s continuous non-contact radar has become increasingly popular in the cement industry since the introduction of 80 GHz frequency radar level sensors to the market.
Radars at this frequency are quite reliable in dust. Their principle of operation is the same, but they are less prone to erratic data or lost signals. They have a 4˚, versus 10˚, beam angle for better precision, and a substantial 393 ft. measuring range.
Radar works by emitting an electromagnetic pulse through the antenna, where the emitted signal is then reflected off the material, then received by the antenna as an echo. The frequency of the received signal is different from the emitting frequency, with the frequency difference being proportional to the distance and the height of the material being measured. The difference is calculated, converted to material height, and output as a measured value using special algorithms contained in the sensor’s electronics.
BinMaster's NCR is reliable for measuring all kinds of rock, sand, and aggregates, including limestone, silica, sand, clay, alumina, bauxite, gypsum, and fly ash.
Radar technology is ideal for silos where precise aiming is needed to avoid internal structures, flow streams, or sidewall buildup. Mount them over piled material, on dome roofs, or in storage bunkers. In large operations, radar is used over conveyor belts to prevent overloading or detect when belts are running empty.
A potential downside of non-contact radar is that it only measures a single point—as does laser technology. Therefore, it is not the recommended instrument when precise volume accuracy is required for inventory management, since it cannot detect the topography of material, irregular piling, or cone-up and cone-down conditions.
The Laser Lowdown: Keep it Clear
Laser is not always ideal for cement because it is best suited for low- or no-dust environments. However, because of its very narrow beam, it is a dependable option for level control in narrow vessels containing solids. It can also be used for plugged chute detection or precise targeting in restrictive chutes and hoppers. Additionally, lasers can detect buildup when installed above the monitoring point or directed toward the sidewall.
A laser sensor is mounted on top of the silo using an adjustable mounting flange that aims the laser at the desired location, generally toward the output of the cone. During configuration, the minimum and maximum distances are set using 4-20 mA inputs that are configured on the sensor. The sensor sends timed laser pulses to the material surface. The distance to the materials is calculated using complex algorithms that convert the laser pulses to a data output. A compensation for "slant range" is made based upon the angle of the beam to ensure accurate level measurement.
The adjustable swiveling mounting flange is flexible up to 10˚. This may allow for use of an existing mounting location and eliminate drilling another hole in the silo roof.
Lasers are easily configured in the field using a USB port without filling or emptying the vessel. Laser has a fast update rate of eight times per second and offers integrated dust protection for minimal maintenance.
One Size Does Not Fit All
Many cement operations use a combination of sensors—both continuous and point level—to keep plants running smoothly. Different size silos, different materials, and different material management objectives will all come into play when selecting the right sensor solution for your operation.
Contact a BinMaster representative for help finding the best solution.
