The raw material used for mulch film is the new PE thermoplastic resin, which is a kind of waterproof barrier film made by a blow molding process. The color is black, the thickness is mainly 0.5 mm and 1.0 mm, the width is 1-8 m, and the roll length is 50-100 m. It is a polymer with non-toxic, tasteless, and odorless characteristics, its melting point is about 130℃, the relative density of 0.95, and also has a good heat resistance and cold resistance. It has high rigidity and toughness, good mechanical strength, and high resistance to environmental stress cracking and tearing strength. The film itself is characterized by low permeability coefficient, high density, uniform thickness, a wide range of temperature adaptation, high elongation, good flexibility, and dimensional stability.
Technical parameters of 1.0 mm mulch film
Rupture strength 27KN
Puncture resistance 32 N
Tear strength 125 N
Carbon black content 2.5%
2 The landfill cover HDPE geomembrane has three functions.
Good impermeability to prevent leakage of leachate.
Good adsorption or degradation properties to remove suspended or dissolved contaminants.
Excellent mechanical properties, welding properties, durability, and sealing properties to ensure the strength and service life of the material.
The weather requirements when laying the mulch film:
The temperature should be above ten degrees Celsius.
The wind force should be below level 4.
When the temperature is too low, it is not recommended laying the film when the wind is above level 4, rain, or snow.
In windy weather, when the wind affects the mulching film laying, the mulching film to be welded should be pressed firmly with sandbags.
3 Covering method of glossy HDPE geomembrane in the sanitary landfill of municipal waste.
First, check and measure the laying area, according to the measured data the size matching membrane will be transported to the corresponding position, when spreading the membrane, according to the actual conditions of the site, by hand in a certain direction, take the way of pushing the laying from top to bottom. It should be extended from the high to the bottom, while not pulling too tightly, and should leave a 5% margin for local sinking stretch. Roll paving process in a timely manner, stretching, and the slope coincides with the flat, no protruding folds. Push pavement should be flat, straight, to avoid wrinkles and ripples. The border should be neat, and the two panels that need to be welded together should be lapped, and the lap width should be controlled at about 15 cm.
The bonding method of mulch film: Before bonding, remove the sand, mud, and other dirty things on the film surface, to ensure that the film surface is clean. Using double-track hot melt welding method.
The upper and lower layers of the impermeable membrane must be overlapped by 15 cm before hot melt welding. The welding process is divided into adjusting the pressure, setting the temperature, setting the speed, checking the lap of the weld, loading the membrane into the machine, and starting the motor. The welding seam must be neat and beautiful, and there must be no slip welding or jumping away. The welding temperature, speed, and pressure are determined after experiments and tests. The edge of the welded seam located in the upper impermeable membrane should be polished into the angle of inclination to improve the welding quality of the seam. The lap width should be not less than 15 cm when hot fusion welding. The thickness of the weld shall not be less than 1.2 times the thickness of the membrane. On the edge of the folded part, cut the cracked wrinkle to ensure a flat overlap. When extrusion welding the cracked or wrinkled excised part, the overlap should be not less than 10 cm. Cross laps should be avoided and a staggered form of ding weld should be used. The welding seam is required to be neat and beautiful, and there shall be no slip welding or skipping away.
Anchoring method of mulching film and ground: It is advisable to use the trench anchoring method, anchoring trench is required to open trench 40 cm from construction plane, trench width 4 cm, trench depth 40 cm, pull the film into the U-shaped trench, and fix it with sandbag or soil.