What are the differences between HPS Defender® Rotary Screens and conventional screens?
Static grids or rotary screens. For large flows or small levels. Made of perforated or grating mesh (Johnson mesh). In 316 or 304 stainless steel. With switchboard and full automation or for adjusting the system to client’s installation… All options are available within Defender Screens and Pre-treatment Equipment range manufactured by Toro Equipment, but this time we focus on a certain range: HPS Defender® Rotary Screens for large flows.
What makes them different?
The most noteworthy feature of HPS Defender® Rotary Screens is their large filtering surface. Whilst conventional screens generally use less than a quarter of the filter drum surface to perform this task, the HPS offer more than two thirds of the whole filter drum surface (fig. 1). This makes an HPS Rotary Screen capable to process almost 5 times more flow than a conventional sieve the same size.
Another main characteristic of HPS Defender® Rotary Sieves is that are standard fitted with a level sensor which activates the drum’s movement according to filtering needs. By this way, the drum is triggered when needed at the required speed. This motion and stopping rotation creates a natural film on filter drum surface which increases even more the performance and effectiveness of filtering. This feature is particularly effective in case of fine particles and fibres (strands, textile, innards, bristles…) and produces a waste drier than conventional screens.
Switchboard in HPS Defender® Rotary Screens gives them a full autonomy. Built-in frequency variator allow to regulate the drum rotation speed, reducing the power consumption. Motor fan engines enable the HPS Screens range rotates at low revolutions with a full guarantee of reliability and durability. Standard programme is adjusted to different filtering requirements, and it can also be customised to meet future needs.
The drum’s internal cleaning system is automated as well. Internal nozzles have a specific direction to reach each area of filter drum. Pressure cleaning is monitored by the switchboard and it can also be set to meet the requirements of each industry and every step.
The scraping system also helps optimise the equipment operation and the dryness of generated waste. This system is adjustable in order to apply more or less pressure on drum depending the product type and quantity to be filtered at any given moment. You can download the Rotary Screen Brochure here.
Importance of Pre-treatment
There are as many possibilities to design a pre-treatment of an effluent as types of wastewater that can be originated in several kinds of industries. Each of them will have specific needs and features, although all of them seek to achieve the same goal.
The importance of pre-treatment lies in the fact that, besides being the first stage of the water treatment process, it also protects the back equipment of treatment plant unit from potential incidents. Sieving supports other equipment (pumps, mixers, tanks…) increasing its durability, reduce maintenance works and ensuring its effectiveness. A good pretreatment help us eliminate all particles with a Ø greater than 0.15 mm, reducing the pollution inlet elfluent.
Benefits of a proper sieving
• Increases the equipment durability
• Increases the energy efficiency and effectiveness of subsequent treatments
• Reduces the maintenance cost
• Improves effectiveness of other equipment and minimises their potential incidents
• Is ‘low cost’ compared to more complex equipment
• It can be executed in small spaces
• It doesn’t need manpower
• Self-cleaning internal drum