CZ31819U1 - A granular filtering material based on modified natural aluminosilicates - Google Patents

Description

Technical field

The technical solution relates to a granular filter material based on modified natural aluminosilicates for removal of heavy metals in particular from rainfall washes from hard surfaces and surfaces in areas of settlements, industrial areas and other urbanized areas with anthropogenic influences.

BACKGROUND OF THE INVENTION

Decentralized rainwater management with subsequent retention, utilization or seepage into the rock environment is one of the necessary tools in the area of measures aimed at mitigating negative impacts of drought and increasing water retention in the landscape. However, sometimes the question is the content of some pollutants in rainwater draining from hard surfaces.

During precipitation, due to wet and dry deposition and especially due to the introduction of contaminants caused by human activity in the form of dripping and shear of corrosive products from metal surfaces, an increased amount of various pollutants is contained in such precipitation.

This phenomenon occurs especially in rainfall from hard surfaces and surfaces in the area of settlements, industrial areas and other urbanized areas with anthropogenic influences.

The highest load is naturally contained in the so-called first shear, when the present pollutants and corrosive products are mechanically washed away and dissolved by the presence of rainwater. It is desirable to separate this first wash over the entire volume of rainwater resulting from a precipitation event, since the contaminants are relatively concentrated therein, and at the same time, the granular filter material and the equipment in which it is stored are not so hydraulically stressed as if exposed water resulting from a precipitation event.

The granular filter material is preferably embedded in the sorption chamber device described in CZ 31015U1 and has the character of a granular flowing stationary bed through which the first rainwater washes flow at a suitable rate. Its character is determined by its chemical composition, processing process and particle size fraction.

In essence, the requirements of ČSN 759010 Rainwater Infiltration Device and TNV 759011 Rainwater Management are fulfilled.

Many filtration materials and sorption preparations are available for use in this field, but often the price is relatively high or the sorption capacity and thus the service life is relatively limited, which reflects the mentioned technical solution.

The essence of the technical solution

The essence of the technical solution is a granular filter material based on modified natural aluminosilicates according to the proposed technical solution suitable for removing heavy metals from the first shear of rainwater coming from the hardened areas of the urbanized area. The material contains particles of 0.5 to 20 mm in size. It is crushed and subjected to sieving on

The desired particle size fraction and washed with water.

The material is superimposed in a stationary filter bed which flows through the first rainwater wash to be processed.

The material is well cohesive and strong and does not degrade mechanically during use.

The material comprises at least 40 wt. % of natural aluminosilicates and up to 60 wt. they comprise additional binders, which may preferably be of the hydraulic or latent-hydraulic type. Due to the addition of binders, the material shows higher strength and mechanical resistance.

The natural aluminosilicates present in the material comprise at least one mineral of the group consisting of albite, heulandite, clinoptilolite, natrolite, celadonite, mullite, chrysotile, muscovite, calcite, hatrurite, orthoclase, montmorillonite, illite, kaolinite, halloysite. 25 wt. based on natural aluminosilicates.

Examples of technical solutions

Example 1

The particulate filter material for the first rainwater shear was obtained by crushing the natural well-cohesive zeolite-based aluminosilicate and sieving a 4-6 mm particle size fraction which was washed with water and the material ready for use.

X-ray analysis revealed the content of the following components: heulandite 40 wt%, clinoptilolite 35 wt%, muscovit 5 wt%.

The detected immobilization capacity for selected heavy metals was 12 mg / g for copper and 7 mg / g for zinc.

Example 2

The granular filter material for first rainwater shear treatment was obtained by mixing 5 parts by weight of the fine-grained phyllosilicate-type natural aluminosilicate with 3 parts by weight of Portland cement and 2 parts by weight of fly ash. The necessary amount of water was added to the bulk material mixture to form a homogeneous well-miscible paste. The paste was allowed to air, set and dry for 15 days. Subsequently, the solidified cured paste was crushed and sieved a 5 to 8 mm particle size fraction, which was washed with water and ready for use.

X-ray analysis showed the following components: mullite 20 wt%, hatrurite 10 wt%, muscovit 10 wt%.

The immobilization capacity found for selected heavy metals was 48 mg / g for copper and 22 mg / g for zinc.

Industrial applicability

The granular filter material for the treatment of rainwater washes from hard surfaces based on natural aluminosilicates is easy to handle and use, the principle of its function is based on the immobilization of pollutants in the shear contained, especially heavy metals. The material is affordable, its processing and treatment is technologically feasible, the raw materials are available, the immobilization capacity for heavy metals is high and the service life is long. After the expiry of the service life is due to low purchase price and chemical

-2GB 31819 U1 does not regenerate.

PROTECTION REQUIREMENTS

Claims (6)

A granular filter material based on modified natural aluminosilicates suitable for removing heavy metals from the first rainwater shear, characterized in that it comprises particles of 0.5 to 20 mm in size. A granular filter material according to claim 1, characterized in that it is crushed and subjected to sieving to the desired particle size fraction and washed with water. The granular filter material according to claims 1 and 2, characterized in that it is part of a stationary filter bed which flows through the first rainwater wash to be treated. Granular filter material according to claims 1 to 3, characterized in that it is well cohesive and strong and does not degrade mechanically in use. The granular filter material of claims 1 to 4, further comprising natural aluminosilicates and additional binders, which may preferably be of the hydraulic or latent hydraulic binder type. 6. The granular filter material of claim 5, wherein the natural aluminosilicates present in the material comprise at least one mineral selected from the group consisting of albite, heulandite, clinoptilolite, natrolite, celadonite, mullite, Chrysotil, muscovit, calcite, hatrurite, Orthoklas, montmorillonite, illite, kaolinite, halloysite, wherein the total amount of said minerals is at least 25 wt. based on natural aluminosilicates.