Environmental protection is the primary subject of today's ecological environment. Natural nanomaterials - bentonite in environmental protection has been widely used in foreign countries. Bentonite can be used as a harmful substance adsorbent, turbid water clarifier, radioactive waste and toxic materials sealant, water contaminated water waterproofing agent, sewage treatment agent, detergent additives, etc., but our country to develop research and application of less.
1. Application in waste disposal
(1) natural sodium bentonite landfill impermeable layer abroad with bentonite blanket (plate), powder to do the landfill impermeable layer of many, especially Germany, South Korea, Japan, the United States, with more, our country has also begun to use. Because bentonite has a high degree of water tightness and self-repair, recovery function, in theory, is close to the perfect impermeable material. 2002 World Soccer Cup stadium in a large landfill built on the top and bottom of the landfill all around the use of bentonite blanket to do impermeable layer. South Korea 15 years ago, the landfill used to build impermeable materials and our previous landfill, impermeable material durability is poor, some serious pollution of groundwater. To repair these impermeable layers and stop leakage, it will cost five times the original cost.
(2) the use of bentonite for nuclear waste disposal and disinfection protection at home and abroad will be the nuclear power plant and other radioactive waste with bentonite thick slurry wrapped in containers buried deep underground practice, the effect is better; foreign use of bentonite to prepare disinfection of toxic agents to protect the first aid kits, there are a wide range of uses.
2. Application in the treatment of waste water and waste oil
(1) bentonite in the treatment of gas scrubbing wastewater with bentonite treatment of printing and dyeing wastewater, gas scrubbing wastewater, monosodium glutamate factory wastewater, waste, removal rate of 99.5%. Some of the wastewater treatment and then the recycled material into feed additives.
(2) with bentonite as animal gasket material to deal with wastewater, odor bentonite can make animal feces easy to disperse, clean up. Domestic demand in large cities has also increased. As captive animal farms and slaughterhouses, aquatic processing plants produce sewage, odor harmful to the environment, can be sprinkled with bentonite in these places, recycling efficient fertilizer, there is a two-for-one effect.
(3) bentonite treatment, adsorption of waste oil with bentonite treatment of fast food frying waste oil, oil is very effective. Bentonite is a very good adsorbent, bentonite adsorption of insulating oil in the electric power industry in foreign countries is very prevalent; oil leaking oil tankers floating on the sea surface, foreign countries are spread on its adsorbent after lump removal.
(4) with bentonite as washing supplies with bentonite washing wool in ancient Rome, ancient Egypt 3000 BC has begun, modern detergents mixed with a certain amount of bentonite, can increase its detergent strength.
3. Application in the treatment of exhaust gases
(1) bentonite treatment of harmful gases abroad with bentonite made of automobile exhaust pipes, filters, mainly to take full advantage of the adsorption of bentonite.
(2) use bentonite to make cigarettes composite filter with bentonite instead of activated carbon can reduce the cigarettes contain tar, free radicals, nicotine and other hazards to the human body.
4. Bentonite in water softeners, clarifiers in the application
(1) in the upper reaches of the reservoir to spread bentonite can make the reservoir unclean material flocculation sinking to the bottom of the reservoir by biological purification to deal with, but also make the reservoir leakage to be cured. Because bentonite can repair the cracks at the bottom of the reservoir.
(2) bentonite can make fruit juice, sugar juice clarification.
(3)Bentonite can soften hard water.
5. Bentonite as seepage control materials can resist saltwater on fresh water, land salinization desertification land in China's 30 provinces, autonomous regions and municipalities of 851 counties and flags are distributed, these desertification soil particles are coarse, generally fine sand, silt, no viscosity, strong water permeability. The bentonite particles are very fine, with strong expansion, viscosity, the two mixed and blended, can be turned into a planting soil that can retain water. Bentonite contains many components that are favorable to the growth of animals and plants, can provide a variety of nutrients for animals and plants.
1. China's distribution of bentonite and several large deserts neighboring, conducive to combating desertification
From the map of China and China's distribution of bentonite can be clearly seen on the map: Hunshandak Sandy, Inner Mongolia, just north of Beijing, from the abundance of bentonite and Xinghe, Zhangjiakou, Chifeng is not too far away; Mao Wusu Sandy, the Kubuzi Desert, Ulaanbaoshan Desert, Tengger Desert, Badanjilin Desert and other nearby bentonite deposits. Xinjiang's Kumutage Desert, Gurbantunggut Desert, Taklamakan Desert are high-quality bentonite deposits on the edge. China's current exploration of the largest bentonite ore reserves of 5 billion tons, quality than the United States of America's excellent, closer to the Gurbantunggut Desert. Torking, Kerching has high-quality bentonite deposits, not far from the Taklamakan Desert. Gansu Jinchang also has bentonite deposits, from the Tengger Desert and Badanjilin Desert are very close.
2. In the desert under the dark river, reservoirs on the sand is very favorable
Bentonite is a very good waterproof material, in the surface layer of sand under a layer of bentonite (a thin layer) can be water storage. Bentonite as a waterproof layer can also build a large number of water storage ponds, pools, libraries, canals, and then the desert under the dark river, reservoirs of water pumped up, stored, slowly used. Recently, the geology department in the northern part of the Tarim Desert surveyed a large amount of water storage underground reservoirs, available bentonite and local soil mixed with the construction of water conveyance channels, the water will be led in all directions.
3. Bentonite has characteristics conducive to desertification management
Bentonite seepage and frost resistance is good; compression and consolidation is good; good stability of the sand; bentonite compactness, self-preservation of water, permanence offset the sandy soil defects; can increase the viscosity of the sand and the ability to retain water; bentonite as an animal feed additives can improve cattle, sheep milk production, chicken Egg production, nutrients, etc., is conducive to animal captive breeding.
4. Bentonite can be quickly constructed storage tanks, water storage cellars, water canals
Bentonite impermeable layer paved with river channels, limited water can be directed to distant places. Bentonite waterproof layer can be used natural sodium bentonite powder directly paved, but also with bentonite and local soil mixing and tamping, but also bentonite sandwiched between the two layers of fabric to form a waterproof (seepage) blankets (panels), rapid construction of water storage tanks, water storage kilns, water transmission channels.
5. Bentonite clay desert soil into a water-saving, fertilizer-saving vegetation soil
Desert moving sand, there is no clay particles, powdered sand is also very little, mainly in the middle and fine sand, water storage, nutrients available for plant growth is also very little, governance, greening, restoration of ecological balance is very difficult. Desertified soil particle size of about 0.01 ~ 0.1mm mostly, very loose, easy to water permeability. And bentonite particle size is more than less than 0.002mm, water can be expanded 10 to 30 times. Therefore, in the sand slightly mixed with some bentonite can prevent water loss, plants can grow.
The most successful foreign governance of desertification in Israel, the barren desert into a water-saving, fertilizer-saving high-yield fields. The southern tip of the U.S. state of Arizona, the closest city to Mexico, Tucson, is a city built in the desert, the city like a forest, but also like a wild botanical garden. The annual rainfall of only 275mm, but can grow hundreds of desert plants and survive a wide variety of animals. The University of Arizona's green lawns have an impermeable layer underneath, as well as sprinklers that spray water at regular intervals, saving both water and energy.
Because desert areas generally have long hours of sunshine and large temperature differences between day and night, the ability to add a canopy over the modified water- and fertilizer-efficient vegetative soil will provide a sizable harvest that year. And in the fly planting green when you can mix the seeds with water first, and then mixed with bentonite clay, its germination rate and survival rate will be greatly improved. Bentonite is also a good carrier of various fertilizers.
6. Application of systematic engineering management of desertification
(1) complete management of desertification, must be selected all over the management of the point, and then point to bring the surface. Selection of points preferably close to the location of the water can be taken, close to the bentonite origin, in order to quickly push the surface from point to point, carpet to the center of the desertification progress, the first thing to do is to store water, build roads.
(2) all parties involved in sand, the use of remote sensing technology to find groundwater, the comprehensive use of solar energy, wind power, new drip irrigation materials and equipment, biological breeding and so on, the application of bentonite for desertification management is very beneficial. Can mobilize, encourage domestic and foreign units, private investment to create benefits, and even initially can mobilize women in major cities will wear broken nylon stockings collected, loaded with bentonite for water cellar waterproofing lining and so on.