With the progress of industrialization and the improvement of people’s living standards, population explosion has become one of the most important problems on earth. In the past years, the earth’s population has continued to grow, and now it has exceeded 7 billion. With the rapid increase of population and the advent of industrial society, 7 billion people on the earth consume a lot of production and living materials every day, and a large amount of garbage is generated. The problem of garbage disposal has become a problem faced by all countries in the world. Except for a small part of degradable garbage, most garbage can not be degraded in a short time. And many wastes will produce toxic and harmful substances after being discarded, causing serious water pollution, soil pollution, and many other environmental problems. In the long run, it will bury hidden dangers for the country and mankind. Thus, waste treatment is an important topic to ensure people’s safety and maintain the sustainable development of the environment.
A used waste treatment way——Landfill
People’s daily production and life will produce a lot of garbage. At present, there are two kinds of waste treatment methods used in the world: incineration and landfill.
Incineration will produce harmful gases, which may aggravate air pollution and the greenhouse effect. The secondary pollution produced by landfill is less and the treatment capacity is large, so it is used for waste treatment.
What does a landfill include?
Garbage landfills are distributed around cities and towns, which are used to treat people’s living and industrial production wastes. The landfill is a very complex system, involving many products and application principles in different fields. It is composed of the bottom gasket system, the top cover system, and the drainage and exhaust facilities.
Omit use, the landfill can be divided into two types: domestic waste landfill and solid waste landfill.
1. Domestic waste landfill: clay liner is used to separate the waste from the surrounding environment. used materials are nonwoven geotextile, HDPE geomembrane, filter screen, and other materials.
2. Municipal solid waste landfill: synthetic (plastic) liner is used to separate the waste from the surrounding environment. used materials are GCL sodium bentonite waterproof blanket, nonwoven geotextile, HDPE geomembrane, three-dimensional composite drainage network, geotechnical filter screen, and other materials. The basic structure of a waste landfill is the bottom liner system; Landfill unit (old or new); Rainwater drainage system; Leachate collection system; Biogas collection system; A cover or cover; Groundwater monitoring station.
Domestic waste landfill needs more filtering and drainage materials than solid waste landfill. Because domestic waste will ferment to produce harmful gas liquid and biogas, the design requirements will be higher.
Landfill Liner——Geomembrane and Geotextile
There are many toxic and harmful liquids and solids in landfill. The accumulation of domestic garbage often produces flammable and explosive gases such as biogas. Thus, it becomes very important to be able to handle waste and prevent leakage.
Landfill liner is designed and manufactured to prevent harmful substances in garbage and waste from leaking and penetrating into the soil, which may cause serious soil pollution and water pollution. In fact, landfill liner is one of the four key elements to creating a safe and safe landfill.
The landfill liner is composed of geosynthetics products, geomembrane, and geotextile. It is important to consider the material and composition of the product to ensure that it can prevent toxic by-products and leachate from migrating to the surface soil, nearby water bodies, and local water sources. Some landfill liners are also used as caps. The cap provides secondary protection against contamination. In a word, the application of geomembrane and geotextile can help keep the wasted, toxic, and harmful by-products.
Geosynthetics have good engineering properties such as anti-seepage, isolation, and reverse filtration, so they play an important role in the bottom liner system of landfill. Common geotechnical products include geomembrane, geotextile, and clay liner. The selection of geotextile and geomembrane is described below.
Introduction of geomembrane
Common geomembranes are HDPE Geomembrane and LLDPE Geomembrane. HDPE geomembrane is the most used material in sanitary landfills and the most stable material among all special geomembrane materials for landfills and landscape projects.
The advantages of HDPE geomembrane as a landfill liner are:
1. High-strength HDPE geomembrane has a compact structure and good resistance strength. The CBR and tear strength data of HDPE geomembrane are both high
2. The anti-seepage ability is good, and the high barrier property of the geomembrane can ensure that the leachate will not leak through the liner to pollute the land, and the landfill gas will not leak through the liner. It can protect the soil and the environment
3. Good chemical stability. HDPE geomembrane is acid-base resistant and high-temperature resistant. It can remain stable even in harsh environments, and will not decompose or lose its anti-seepage ability
4. It has good UV aging resistance, and HDPE geomembrane contains about 3% carbon black. The addition of carbon black enhances its UV resistance and stability. Since there is no plasticizer in the HDPE geomembrane, there is no problem with ultraviolet radiation decomposition. Its life span is very long. HDPE geomembrane can be used for 10-20 years under the sun, and even 50 years buried under the ground
5. The construction and welding are convenient and the construction technology is mature. There are a variety of welding machines for the welding of geotechnical products, such as hot air welding machines, extrusion welding machines, etc. The use of the welding machine is very simple and does not need too much investment in manpower and material resources. A welding machine can be used for a very long time and is very cost-effective
Specification and selection of Geomembrane
The specification parameter of HDPE is thickness. The common thickness in the landfill site is 1.0mm, 1.5mm, and 2.0mm, and can also reach 3.0mm if necessary.
In addition, the surface of the HDPE geomembrane has a smooth surface and textured surface. Thus, there are three kinds of surfaces that can be selected for geomembrane liner: Double smooth surface, double textured surface, and one smooth and one textured surface.
Because landfill is usually a large project, the size of the geomembrane roll is usually large. In this case, the smooth geomembrane is too easy to slide, which is not conducive to the operation of workers. Thus, single-textured or double-textured geomembranes are usually used in large landfill projects. A textured surface geomembrane can produce greater friction, which is convenient for workers to install. At the same time, because it needs to form a composite structure with the geotextile, the friction of the textured surface geomembrane can make the geotextile fixed, and the two are not easy to slide. Textured surface geomembrane is processed on the basis of smooth geomembrane. The price is higher but it is completely reasonable.
Introduction of Geotextile
Geotextile is a new type of geosynthetic product, which is a permeable geosynthetics made of synthetic fibers by needling or weaving. There are PP and PET materials of geotextile fabric, which can also be divided into woven geotextile and non-woven geotextile according to the process. Geotextile has excellent isolation, filtration, and water permeability, and can be used in many fields. Today, we introduce the properties and application examples of geotextiles, to help you understand the performance of geotextiles and make choices according to your projects.
Specification and selection of Geotextile
When selecting geotextiles, there are three specifications to be determined, that is, material, fiber, and GSM. These three items also determine the price. The prices of different materials and weights can vary greatly. After determining these three items of data, you can customize the width and roll length according to your own needs.
1. Material. The most common raw materials for geotextiles are PET (polypropylene) and PP (polyester). PET geotextile and PP geotextile both have good water permeability,tear-resistance, and stability. But the acid resistance and alkalinity of the two are different.
2. The fiber length of geotextile includes long filament and short filament. For the same GSM, the tensile property of long filament geotextile is better than that of short filament geotextile, and the price is higher, but it is worth it.
3. GSM, means the weight per square meter geotextile. Generally, within a certain weight range, the price per ton of geotextile is fixed. Therefore, the unit price of geotextile with different weights per square meter is different now. The greater the weight of the geotextile per square meter, the thicker the geotextile, and the higher the price. Under the same materials and processes, there is no doubt that the thicker the geotextile, the better the tensile strength. And so it can bear more external pressure and impact. Therefore, the protection capacity and service life are longer. Because different layers of geotextile may play different roles in the project, the weight meeting the requirements can be selected according to the function of the geotextile layer.
The following is the technical data of PET long filament geotextile. You can choose the appropriate weight of geotextile according to your engineering strength and practical application.
How to find cheaper suppliers of geosynthetics products
At present, geosynthetics products, as common products in the construction and geotechnical industries, have been very common. There are manufacturers and distributors in many countries in the world. But, not all countries have geosynthetics products factories or enough supply of geosynthetics products. The market of geosynthetics products varies from continent to continent and from country to country. This has also promoted international trade between many different countries. As we know, China has a large number of geosynthetics factories, which produce various geosynthetics products, based on HDPE geomembrane / LLDPE geomembrane and geotextile.
Because China has become a global factory base, China’s factories are large in scale and quantity, and the products are low in price and high in quality. At present, almost all geosynthetics factories provide customized product services. Buyers can customize various specifications according to their needs, such as the thickness, width, and surface of geomembrane, as well as the weight, fiber, and process of geotextile. At the same time, Chinese suppliers also provide technical consulting and perfect logistics services.
Most, China has the lowest price in the world. Whether in Europe, America, Africa, or Oceania, China’s price can compete with all local factories or suppliers. In some countries with undeveloped industries, the price of local geosynthetics products is dozens or even hundreds of times that of Chinese manufacturers. Under such circumstances, importing geomembrane and geotextile from Chinese factories has become the best choice to save costs. At present, many buyers in Africa, Southeast Asia, and Oceania are used to importing geotextile and geomembrane from China.
Thus, if you have large-scale projects such as landfill and landscapes, I recommend that you learn about the price in China first and compare them with the local price. Most of the time, the price of products exported by Chinese factories is lower, which is definitely a good choice for you to save cost.