RU2256623C1 - Biofilter filling - Google Patents

Abstract

FIELD: waste water treatment.

SUBSTANCE: filling for biofilters used for treatment of waste waters, in particular those from petroleum processing and petrochemical enterprises, contains nonwoven polypropylene material with porosity 80-230 μm, thickness of canvas 0.30-0.55 mm, which is used in amounts 0.45 to 1.43 g/L.

EFFECT: increased strength and created favorable conditions for immobilization of microorganisms and aquatic organisms.

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Description

The invention can be used in the wastewater treatment process, in particular in the oil refining and petrochemical industries.

Known loading for a biofilter (Japanese application No. 60-14637, C 02 F 3/08, 1985), representing a strip, tape or cord made of plastic lighter than water, the upper and lower ends of which are fixed on the clamps.

The disadvantages of such loading elements for biofilters are the low degree of wastewater treatment from petroleum products and the low strength of the loading elements.

Known loading for biofilters (application France No. 2565579, 02 F 3/00, 1985), which is a glass fiber connected in a cylindrical brush.

The disadvantages of such a load for biofilters are the low degree of wastewater treatment from petroleum products and the low strength of the loading elements.

Known loading for biofilters (USSR author's certificate No. 1560486, C 02 F 3/04, 1990) from corrugated plastic sheets and gaskets between them in the form of strips or strings.

The disadvantages of such a load for biofilters are the low degree of wastewater treatment from petroleum products and the low strength of the loading elements.

Known loading for biofilters (RF patent No. 2091332, C 02 F 3/04, 1997) from the frame with a polymer fibrous material deposited on it by pneumatic extrusion with porosity (35-40) - (90-95)% and fiber thickness ( 5-10) - (400-500) microns.

The disadvantages of such a load for biofilters are the low degree of purification of wastewater from oil products and the low strength of the polymeric fibrous material.

Known loading for biofilters (RF patent No. 2061661, C 02 F 3/04, 1997), in which the sheets of the frame are made of a polymer material with a porosity (200-300) - (500-1000) microns and a thickness of 3-20 mm by pneumatic extrusion.

The disadvantages of such a load for biofilters are the low degree of purification of wastewater from oil products and the low strength of the polymeric fibrous material.

The closest in technical essence and the achieved effect is loading for biofilters (Istomina L.P., Naumenko I.V., Perevozny V.G. Use of a flat nozzle for intensification of biological wastewater treatment. Chemistry and Water Technology, 1990, 12, No. 3, p.272-275), which is a synthetic non-woven material, which consists of 50% viscose fibers and 50% nitron, called “flazilene”.

The disadvantages of such a load for biofilters are the low degree of wastewater treatment from petroleum products and the low strength of flazilene.

The proposed load for the biofilter contains a non-woven polymer material - geosynthetics with a porosity of 80-230 microns and a web thickness of 0.3-0.55 mm in an amount of 0.45-1.43 g / l.

Geosynthetics are made from 100% polypropylene having a density of 0.91 g / cm ³ and a melting point of 165 ° C by thermal bonding of continuous fibers with a diameter of 60-300 μm calendering. The resulting material has a silver color, high rigidity and water permeability. It has good resistance during road construction to increase the bearing capacity of the soil base, to separate the layers of pavement, for the installation of drainage structures, for the construction of roofs, etc.

The proposed use of it for a new purpose provides a high degree of purification of wastewater containing oil products, and a higher strength of biofilters compared to the materials used at present.

In addition, the proposed material can be used in finished volumetric loading modules of any design, which creates the most favorable conditions for the immobilization of microorganisms and hydrobionts.

The following examples of wastewater treatment from petroleum products demonstrate the effectiveness of the use of geosynthetics for a new purpose.

The experiments were carried out in laboratory conditions using a bioreactor with a capacity of 16 l with three nozzles fixed on it on metal square frames with a side size of 20 cm and a sump. Water purification in the bioreactor was carried out under conditions of intensive aeration with an air supply rate of 20 m ³ / m ² · h. The cleaning time was 6 hours. Then the purified water was fed into the sump, where it was separated from the excess sludge.

For analytical control of water, generally accepted methods were used (Lurie Yu. Yu. Analytical chemistry of industrial wastewater. - M.: Chemistry, 1984).

For the experiments, the waste water of the Tuapse refinery was used with an oil content of 7.63 mg / L and 29.4 mg / L and a pH of 7.8-7.9. The purification temperature was 27–29 ° C. Activated sludge was used as a biocenosis, which contained microorganisms such as arthrobacteria, for example Arthrobacter siderocapsulatus, Arthrobacter tumescens, iron bacteria, for example, the genus Leptothrix and others.

After the experiment, the nozzles were freed from sludge and dried. All nozzles before and after the experiment were determined by tensile strength according to the European standard EP ISO 10319.

Example No. 1

Geosynthetics nozzles having a strength of 7.6 kN / m ² , with a porosity of 135 μm and a thickness of 0.42 mm, which was 0.94 g / L, were placed in a 16 L bioreactor.

On the nozzle, biocenosis from activated sludge was increased to a biomass concentration of 0.1 mg / L. Then wastewater was supplied with a pH of 7.86, containing 7.63 mg / l of petroleum products, and air at a speed of 20 m ³ / m ² · h. The purification temperature was 28 ° C.

After 6 hours, the purified water was transferred to a sump, where for 3 hours the water was sedimented from excess sludge and then taken for analysis.

The nozzle was removed from the reactor, cleaned of overgrown biomass, dried and tested for strength.

The test results are presented in the table.

Example No. 2

Wastewater treatment was carried out according to example No. 1 with the difference that a geosynthetic with a strength of 3.0 kN / m ² , porosity of 230 μm and a thickness of 0.35 mm was used as a nozzle. The number of nozzles in the bioreactor was 0.51 g / L. The purification temperature was 27 ° C, and the pH of the wastewater was 7.8.

The test results are presented in the table.

Example No. 3

Wastewater treatment was carried out according to example No. 1 with the difference that a geosynthetic with a strength of 12.1 kN / m ² , porosity of 80 μm and a thickness of 0.55 mm was used as a nozzle. The number of nozzles in the bioreactor was 1.43 g / L. The purification temperature was 28 ° C, and the pH of the wastewater was 7.9.

The test results are presented in the table.

Example No. 4

Wastewater treatment was carried out according to example No. 1 with the difference that a geosynthetic with a strength of 3.2 kN / m ² , porosity of 230 μm and a thickness of 0.30 mm was used as a nozzle. The number of nozzles in the bioreactor was 0.45 g / L. The treatment temperature was 27 ° C, the pH of the wastewater was 7.8, and the amount of petroleum products in the wastewater was 29.4 mg / l.

The test results are presented in the table.

Example No. 5 (comparative)

Wastewater treatment was carried out according to example No. 1 with the difference that a geosynthetic with a strength of 15.3 kN / m ² , porosity of 70 μm and a thickness of 0.59 mm was used as a nozzle. The number of nozzles in the bioreactor was 0.61 g / L. The purification temperature was 27 ° C, and the pH of the wastewater was 7.8.

The test results are presented in the table.

Example No. 6 (comparative)

Wastewater treatment was carried out according to example No. 1 with the difference that a geosynthetic with a strength of 2.6 kN / m ² , porosity of 230 μm and a thickness of 0.25 mm was used as a nozzle. The number of nozzles in the bioreactor was 0.45 g / L. The purification temperature was 27 ° C, and the pH of the wastewater was 7.8.

The test results are presented in the table.

Example No. 7 (comparative)

Wastewater treatment was carried out according to example No. 1 with the difference that a geosynthetic with a strength of 15.3 kN / m ² , porosity of 70 μm and a thickness of 0.59 mm was used as a nozzle. The number of nozzles in the bioreactor was 0.61 g / L. The treatment temperature was 27 ° C, the pH of the wastewater was 7.8, and the amount of oil in the wastewater was 29.4 mg / L.

The test results are presented in the table.

Example No. 8 (comparative)

Wastewater treatment was carried out according to example No. 1 with the difference that a geosynthetic with a strength of 2.6 kN / m ² , porosity of 230 μm and a thickness of 0.25 mm was used as a nozzle. The number of nozzles in the bioreactor was 0.45 g / L. The treatment temperature was 27 ° C, the pH of the wastewater was 7.8, and the amount of oil in the wastewater was 29.4 mg / L.

The test results are presented in the table.

Example No. 9 (comparative)

Wastewater treatment was carried out according to example No. 1 with the difference that the number of nozzles was 0.40 g / L.

The test results are presented in the table.

Example No. 10 (comparative)

Wastewater treatment was carried out according to example No. 1 with the difference that the number of nozzles was 1.55 g / l.

The test results are presented in the table.

Example No. 11 (prototype)

Wastewater treatment was carried out according to example No. 1 with the difference that flasilene with a strength of 0.8 kN / m ² , porosity of 420 μm and a thickness of 0.03 mm was used as a nozzle. The number of nozzles in the bioreactor was 0.25 g / L.

The test results are presented in the table.

Example No. 12 (prototype)

Wastewater treatment was carried out according to example No. 11 with the difference that the oil content in the wastewater was 29.4 mg / L.

The test results are presented in the table.

As can be seen from the materials presented, the proposed loading for biofilters using a non-woven material from polypropylene - geosynthetics - has high strength and can increase the degree of purification of wastewater from oil products.

However, achieving high cleaning performance is only possible using geosynthetics with declared porosity, thickness and quantity in the bioreactor (pr. No. 1-4).

So, when using geosynthetics with low porosity and high wall thickness (pr. No. 5 and 7), the degree of purification decreases sharply, which can be explained by a decrease in the flow rate through the nozzle.

When reducing the wall thickness below the declared (pr. No. 6 and 8), the degree of purification decreases slightly, and the strength of the nozzle decreases.

The material for the biofilter - geosynthetics - with a higher porosity is not available.

With a small number of nozzles in the bioreactor (Project 9), the degree of purification of wastewater decreases, and with a large number (Project 10), the treatment remains at the same level, but the flow rate decreases.

Comparison of the proposed biofilter with a biofilter, in which flazilene is used (according to the prototype, pr 11 and 12), show the high efficiency of the biofilter using geosynthetics.

Table
The results of experiments on the treatment of wastewater from petroleum products using the proposed biofilter Example No. Nozzle characteristic Test results name amount of nozzle, g / l porosity, microns Thickness mm oil content, mg / l degree of purification,% Strength, kN / m ² at the entrance to the reactor at the outlet of the sump to experience after experience 1 geosynthetics 0.94 135 0.43 7.63 0.38 95.02 7.6 6.9 2 also 0.51 230 0.35 7.63 0.26 96.54 3.0 2.2 3 “-“ 1.43 80 0.55 7.63 0.25 96.76 12.1 11.6 4 “-“ 0.45 230 0.30 29.4 6.43 78.12 3.2 2,3 5 wed “-“ 0.61 70 0.59 7.63 3.96 48.10 15.3 14.7 6 wed “-“ 0.45 230 0.25 7.63 0.41 94.63 2.6 1,2 7 wed “-“ 0.61 70 0.59 29.4 23.64 19.60 15.3 14.8 8 wed “-“ 0.45 230 0.25 29.4 6.99 76.24 2.6 0.9 9 wed “-“ 0.40 135 0.43 7.63 4.01 47.44 7.6 6.9 10 wed “-“ 1.55 135 0.43 7.63 0.40 94.75 7.6 6.5 11 ave. flazilene 420 0,03 7.63 2,4 68.50 0.8 Nozzle torn 12 ave. “-“ 420 0,03 29.4 19.86 32,50 0.8 also

Claims (1)

A loading for biofilters containing a polymeric material, characterized in that the non-woven material made of polypropylene is a polymeric material - a geosynthetics with a porosity of 80-230 microns and a web thickness of 0.30-0.55 mm in an amount of 0.45-1.43 g / l