Mechanical treatment

The Defender® compact pre-treatment plant is a complex equipment that allows the implementation of several processes simultaneously: straining, removal of sand and grease. These facilities include a channel screen conveyors or compacting auger, 2 pcs. screw conveyor (longitudinal and inclined), sand and grease removal bath-tub and scraper system. Once the solids have been filtered, compacted and removed, the equipment is equipped with a fine aeration system located at the bottom of the bathtub, which allows the fat to rise to the surface. The grease is then removed by a scraper trapping system located at the end of the sand and grease removal bath-tub, which transports it to the edge of it from where it is gravitationally extracted by pipe.

Defender® grit classifiers are used in the second phase of pre-treatment of raw water to extract suspended solids (gravel, sand and mineral particles). The purpose of the treatment with the offered equipment is to prevent clogging of the channels and pipelines, to protect the rest of the equipment in the installation from abrasive impact and to alleviate the load in the operation of the next treatment facilities. The grit classifiers consist of a chamber for entering the raw water (made of polyester, reinforced with fiberglass (FRP) or stainless steel) and a hollow chute with an installed screw that captures, retains and transports solid particles. Advantages of the offered equipment are its easy cleaning and maintenance, convenience for inspection through a hatch, design preventing problems with congestion and air tightness and high efficiency (removes up to 97% of sand particles up to a diameter of 0.15 - 0.2 mm).

The offered equipment allows performing a number of activities related to mechanical treatment of wastewater, including: compacting, transporting, dewatering and mixing of undissolved substances and / or sludges. Compacting screws (augers), serve to compact and dehydrate retained solids, transporting screws assist the transfer of retained substances to their collection point, and mixing screws allow the homogenization of various materials (most often sludge and lime).

Depending on their principle of operation, the proposed screens (grids) can be divided into static and rotary. In the first type the water is filtered through a static sieve, which separates solids from the treated water, which collects at the base of the equipment naturally due to the inclination of the grid itself. In the second type the sieve rotates assisted by a reducer, there is an installed barrier and a chute, which help the separation of the retained substances, and the nozzles installed in this type of equipment additionally protect from clogging. Another type of grille offered allows installation in open channels, in which case an auger installed in the equipment removes and compacts the captured solids.