Recycling Method Of Crosslinked Polyethylene
XLPE is widely used in wire and cable coating layer, motors, transformers and other high voltage resistance, high frequency of heat-insulating material, heat-shrinkable film and tube, all kinds of pipe (such as hot water pipes ), corrosion-resistant components of chemical production equipment, containers, foam and other fields with its superior performance.
Currently in the US and European markets, cross-linked polyethylene pipe is the most widely used plastic pipes. According to building statistics for the European market with respect pipes for hot and cold water pipes and heating system, in 1996,cross-linked polyethylene pipe tubing (including metallic and non-metallic pipes) accounted for 24% of total consumption, accounting for 60% of the plastic pipe.
Plastic pipe is booming in China. Chinese current use galvanized pipe tubing ,are mainly used for water pipes and gas pipes, PVC pipe for drainage pipes and casing, brass and stainless steel pipe are used for water heating pipe of advanced architecture. As a national industrial policy, vigorously promote the chemical building materials, in terms of plastic pipe, and new high-quality plastic pipe will instead of the original metal or other pipe is an inevitable trend.
Cross-linked polyethylene pipe has been included in the ranks of new type of building material, and as the national well-off residential recommended products, has been widely used in commercial buildings, apartments, commercial housing, factory buildings, solar energy, water and other urban areas, and will use in a broader market.
Recycling, reuse of waste XLPE insulation method, the following steps are:
a) Cleaning, drying, grinding;
b) Crushed waste XLPE and added accessories (such as recycled polyethylene), emollients, coloring agents and fillers or by a certain percentage of ingredients;
c) the ingredients kneaded, extruded in an extruder qualified plastic strip or tablets, is an ideal material for cable filler pipe used in construction, low-voltage electrical accessories and civilian instruments making.
It can operate under conventional conditions, with a simple process, low cost, low investment and high efficiency advantages.
XLPE recycling methods:
1 powdered filler recycling method, the waste XLPE scrap was grinded to powder filler after sorting, cleaning, and directly molding with other thermoplastic blends, it is simple regeneration recycling technology.
2 hot cutting plastics recycling technology, the substance of the heat recycling process is plasticized shearing thermal oxidation and mechanical shear force, XLPE macromolecular main chain carbon-carbon bond damaged and the molecular structure tends to be non-body, thereby increasing the thermoplastic material.
3 supercritical fluid processing recycling method, based on the extruder through improved continuous processing equipment, using supercritical water or alcohol and the like of the silane cross-linked polyethylene chemical reaction hydrolysis or alcoholysis selectively interrupt the like of the Si-XLPE silicon-oxygen bond, thereby undermining its crosslinked structure and reply plastic, recycled material to obtain a thermoplastic mechanical and electrical properties comparable to pure PE.
4 out of ultrasound-assisted recovery technology, can produce high-frequency ultrasonic field stretching stress in a variety of media, high amplitude shock wave can cause local breakage of solid and liquid cavitation, using acoustic cavitation energy can be focused on the molecular bonds to selectively destroy the three-dimensional structure of a key part of the energy associated with a lower key, while retaining the macromolecular main chain, so as to achieve the purpose of cross-links regeneration.
5 Solid Phase cut milling recycling process, is a new technologies that polymer-based material by Pan Mill reactor built up solid state shear pulverization processing. The reactor has a unique three shear structure, have a strong crushing, shearing and hoop stress. With solid state shear milling technology has been successfully achieved solid waste XLPE power chemical crosslinking solution and recycling.