Vermiculite For Filtration Media and Effluent Treatments
Purification of industrial and domestic sewage, spills of petroleum products, organic and toxic liquids
Adsorbent vermiculite appointed for filtration of effluent treatment Power Plants and enterprises (industries with domestic), as well as elimination oil spills, organic and toxic liquids from the solid surface and surface waters.
Adsorbent vermiculite has a high sorption properties for a number of organic impurities. He, like charcoal, acquires hydrophobicity, which allows to use it, in particular, for water purification.
|The chemical composition of the adsorbent vermiculite|
|The percentage of||34-36||6-18||14-25||1,2-2||3-5||5,6-17||6,8-8||0,2-1,2|
|Physical properties of the adsorbent vermiculite|
|Color||Yellow, golden or silver|
|Average density||65-150 kg/m3|
|Melting point:||1350 °C|
|Water intake||Up to 450% by weight|
Note : The average density and water absorption vary with the size fraction.
|Duration of biosorberov||Place selection||pH||CПAB||BПK 02/l,mg||Suspension mg/l||Nitrogen, mg/l||Phosphate, mg/l|
Note : The measurement of water temperature 8 – 10 º C.
|Petroleum||Absorption of 1litre of expanded vermiculite № fraction|
|Diesel oil||290 350||350||400||250||120|
When cleaning industrial and domestic waste water as a filter used adsorbent vermiculite, which is pumped through the contaminated water.
When loading of the adsorbent should take into account the guaranteed rate of exhaustion of the maximum sorption capacity of vermiculite Ksb – 0,7.
Sorption capacity of 1,6-3,5 g / g depending on the intensity of aeration of the solution.
Collection of oil from solid surfaces
To remove oil from hard surfaces should be used vermiculite with a grain size not less than 1,25 mm. This sorption capacity varies from 1,9-5,9 g / g.
Poured petroleum to be processed adsorbent vermiculite (vermiculite is dispersed a diffuse surface). Adsorbent absorbs oil for 10-15 minutes, after which you must remove it from the surface.
Reclamation of land
The contaminated land applied a mixture of adsorbent vermiculite (1 part) and peat (2 parts).
In this case, the adsorbent vermiculite absorbs hydrocarbons, creates an environment for the development of oil-oxidizing soil bacteria present in natural biogiotsenoze the region.
The adsorbent vermiculite is air-induces, store water and pH correction additive to the soil substrate.
Adsorption of organic substances
Application of adsorbent vermiculite can:
Reduce the BOD 2-3 mg / liter. (initial value of 20-25 mg / l)
Reduce phosphates 10-15 times, until 0,3-0,2 mg / l (reference value 3-5 mg / l)
Reduce ammonia nitrogen to 1-3 mg / l (reference value 10-15 mg / l)
Reduce nitrates to 3-4 mg / l (reference value 10-15 mg / l)
To reduce nitrite to 0,0001-0,0002 mg / l (reference value 3-5 mg / l)
The necessary contact time for removal At high concentrations (flooding): Determined by the treatment of difficult to recoverable components and is 5-6 minutes.
At low concentrations (30-50 mg / l)
In flow-through filters meet the requirements, where the linear velocity of filtration for adsorbents with a dense layer of downloads is limited to the size of 12 m / h, ie works better than activated carbon. Accordingly, the rate of contact is determined by the thickness of the load and the selected linear velocity filtering (not exceeding 12 m / h).
Regeneration of the sorbent
The used sorbent is not economically advisable to regenerate, because vermiculite cost significantly less than the cost of its regeneration, and the difference of costs not offset by the value of lessons during cleaning of oil. As a result, vermiculite is being recycled.
Recycling adsorbent vermiculite after collecting oil:
The collected oil can be mixed with coal for Thermal power, but more promising and cost-effective method is an incinerator with pseudo liquid layer. Incinerators utilities can take waste with calorific value between 714 and 1190 kJ / kg, and incinerators for incineration of industrial waste can take all kinds of waste. After firing at a temperature of 250-300 °C possible reuse of the adsorbent
2.Plowed into the soil
For site selection should take into account the presence in this place the water intake and permeability of the soil. Burial must bank and provide drainage channels. Maximum number of petroleum products, distributed on the surface during burial, less than 10 kg/m ³. Plowing is made of 1 times per month to 1 times per season after 2 years. For successful processing of petroleum oil-oxidizing bacteria of the soil pH must be at least 6.5. This technology is used for the disposal of sludge oil refineries for many years.
Adsorbent vermiculite immobilized bacteria, petroleum refining, in activated sludge. After some time spent sorbent oil remains. When the experiment was taken adsorbent vermiculite saturated with oil up to 80%, and placed on the city dump with a layer of 30 cm. After 2 weeks in the spring-autumn period, petroleum products have been fully processed oil-oxidizing bacteria.
Disposal of sorbents containing organic matter, phosphates, nitrates, nitrites, ammonia nitrogen, is similar.