TypesGenerally, ECON's underwater pelletizers are offered in combination with the water treatment and drying system (EWT).
The vibration drying system consists of two or three sequentially arranged vibrating screens. The first stage serves for dewatering the pellets. In a dehydrator, the pellets are separated from the process water before they enter the screen. The process water is cleaned by an automatic band filter and recirculated to the process.
In the second stage, the pellets undergo further drying. Electrical damping registers are installed under the vibrating screen to generate a warm stream of air through the screens.
An additional stage can be installed to treat highly hydroscopic materials with even more stringent requirements for residual humidity.
TypesThe ECON vibration drying system is suitable for throughputs up to 3,000 kg/hr.
The air pelletizing system consits of a pelletizing unit, a conveyor fan with noise reduction cover, piping and a cyclone and an electrical control system.
The melt is directed to the pelletizing head with the die plate installed, and the emerging melt strands are pelletized.. The pellets are moved by an air stream that is produced by the conveyor fan. By the air stream the pellets are dried and are discharged through the cyclone.
The granules/water mixture is supplied to the drying chamber through the inlet case, which is incorporated as a sieve in the bottom. The granules are collected in the drying chamber by a rotor equipped with blades and are spirally conveyed upward through the sieve basket. The water is collected by bouncing and rolling the granules frequently on the sieve basket. The dried product leaves the dryer in the airflow through the tangentially arranged nozzle on the dryer top cover. The water outflow takes place through an outlet in the bottom of the housing or in the housing side.
To change the screens the machine has to be stopped. The piston carrying the screen is moved out hydraulically and the screen can be exchanged.
The discontinuous screen changers are appropriate for throughputs from only a few kg/hr up to 2,500 kg/hr.
The piston in the backflush unit redirects the melt flow, so only one piston with screens is currently being used in the production process. The other screen pack is flushed backwards, so any contaminants with only minimal melt are removed from the screens through the backflush unit. Afterwards the process is repeated with the other screen pack.