– the technology allows to recuperate plastic and metal.
– Technological process provides non-waste production and ecological cleanliness.
Proposed process of utilization of used disposable syringes involves separating of polyethylene parts from metal needles by dissolution (washing) of polyethylene by specially developed eutectic mixture of solvents with subsequent recuperation of the latter for multiple use and achieving non-waste technology in such a way.
Advantage: – there are no similar technologies.
Key process steps which require appropriate equipment:
– preparation of eutectic mixture of solvents;
– washing of polyethylene;
– recuperation of eutectic mixture of solvents.
Preparation of eutectic mixture of solvents is carried out in a closed container (barrel) fitted with inlet and outlet nozzles with shut-off valves (faucets), level gauge and stirrer.
Polyethylene washing is carried out in a unit similar to the conventional unit for metal products degreasing in the vapor of solvents.
This unit is a vertically mounted barrel with a removable pressure cap in the top.
Barrel, about in its middle part, is divided horizontally by wheelwright (false bottom with apertures).
Loading-unloading basket with washed parts (in this case – used syringes) is placed on the wheelwright.
Solvent evaporator is placed under the wheelwright.
The simplest design of the evaporator by itself is the lower part of the barrel with an external heater (TEH, steam jacket, burner, etc).
This unit is equipped with pressure regulator on the top, in the basket area, and the solvents vapor condenser (usually water coil) to ensure uniform circulation of washing solvent vapors.
Drain valve to drain “dirty” solvents for their further recuperation is installed at the bottom of the unit.
Recuperation of the eutectic mixture of solvents is carried out by their distillation (evaporation and further condensation).
At the first approximation the distillation unit is a “hootch still” which structurally is provided with unload of useful bottom products, in this case, powder-flakes of polyethylene.
Highly technologically distillation is carried out under reduced pressure – it hardly reduces the energy consumption and agglomeration of bottom products.
Basic data for design of utilization unit of used disposable medical syringes.
The basis of the method of utilization of used disposable medical polyethylene syringes is a process of high-temperature selective separation of polyethylene parts from the metal needles by dissolution (washing) of polyethylene with a complex solvent which is a specially developed eutectic mixture of solvents.
The technology provides
– further full recuperation of solvent for the purpose of its multiple use,
– separation of the valuable metal, high-alloy scrap steel,
– disengagement of polyethylene suitable for further re-use,
– ensuring of non-waste technology.
Key process steps which require appropriate equipment and devices: – sorting of utilizable waste.
The elements of syringes or droppers which contain steel inserts are separated on the sorting table;
– preparation of the eutectic mixture of solvents.
Preparation of eutectic mixture of solvents is carried out in a closed container (barrel) fitted with inlet and outlet nozzles with metering device and shut-off valves (faucets), level gauge and stirrer.
The eutectic mixture of solvents is used with specially developed features.
Solvent consumption is caused only by the culture of technological process.
As a result, we get separated metal and polyethylene.
Metal needles can be used as raw material for production.
Note: – sorted plastic elements of syringes or droppers that do not contain metal inclusions are processed by simple, well-known thermal methods (simple melting and subsequent granulation in order to reuse.
The approximate cost of the equipment for processing of 1 000 000 used syringes and droppers in 1 change (8 hours) or 22 000 000 in 22 working days a month, – will make about 150 000 US dollars. – 2009
If you are interested – we will provide additional information and designer’s supervision over implementation of the technology.
p.s. We expect proposals for mutually beneficial cooperation