FR2608587A1 - Process for the purification of industrial effluents using "lithotamnium calcareum" - Google Patents

Abstract

The process for purification of industrial effluents involves passing these industrial effluents through a column of screened and dried Lithotamnium Calcareum, which has a particle size of between 10 mm and 0.1 mm. The industrial effluent capable of being treated by this process may contain one or more of the following ions: nickel, zinc, copper, cadmium, iron, indium, manganese, molybdenum, cobalt, ruthenium, titanium, phosphate, sulphate, fluoride, iodide, caesium.

Description

 The process consists in the elimination of one or more undesirable compounds in the effluents of industrial origin. This purification is carried out by the passage of industrial effluents in a column containing screened Lithotamnium Calcareum. dried. having a particle size between 0.1 mm and 10 mm.

 The use of this product is known for the deacidification of drinking water, but never a process involve this product had not been carried out to treat industrial effluents polluted by the following cations nickel, zinc, copper, cadmium iron indium, manganese .

molybdenum, cobalt, ruthenium, titanium, cesium and the following anions phosphate, sulfate, fluoride, iodide.

Lithotamnium Calcareum is a calcified alga from the calcification of families following the Cryptonemales. lei Corallinacbes and Melobosiees, the main ones of which are. are the following
- Calcium carbonate 84 S + or - 4 S
- Magnesium carbonate 1 11% + or - 3
- Sulfur 0.6 S + or - 0.2%
- Phosphorus 0.35 .S + or - 0.1%
-Chlore 0.2% + or - 0.15%
-Potassium 0.2 ',, + or - 0.15 t-
-Sodium u.17 + or - 0.1 -t 'and with the following physical characteristics
The natural product, to be effective. must be screened and dried so that industrial effluents are in intimate contact with it
The bulk density is between 1.04 and 1.0s, the actual density being 2.7. This product has very high porosity. it is in particular this characteristic which explains its superior performance compared to the product of similar chemical nature used previously.

The dimensions of the natural product can range up to 5 cm and more. We have explained that the implementation of the product which makes it possible to obtain good results requires drying and screening of the
Lithotamnium Calcareum to have a particle size between 0.1 mm and 10 mm and we found that the results were even better for a screening between 0.5 and 4 mm.

The passage of the effluent takes place in a column lined with
Lithotamnium Calcareum. The micro-porous structure of the product as well as the particle size make it possible to obtain an effective product. industrially usable. which is not. the case with products such as lime. dolomite. or giobertite which, although currently used industrially, clogs up when put into service or creates a road
During which the effluent flows, leading to an ineffective purification.

One of the characteristics of the product is its capacity to preserve the purified impurities without loosening them by leaching.
The process uses a column containing the Lithotammum Calcareum.

The flow rate of the effluent passage will depend on the load of impurities in the effluents. As an indication, a column containing 1 m3 of
Lithotamnium calcereum can be crossed by an effluent with a flow of 1 m3 per hour. In the case of low load. the flow rate could be 10 m3 per hour. and in the case of a higher load it can be reduced up to 0.2 m3 an hour.

 EXAMPLE I Installation for surface treatment before paints using crystalline phosphating agents.

In such a way that the paint layers can adhere to the metallic steel surfaces. aluminum. zinc. it is necessary to carry out the phosphating of these surfaces. This phosphating can take place in so-called crystalline phosphating baths containing the following phosphate ions. zinc. nickel, iron, titanium. manganese. Used products as well as rinsing water are rejected and therefore phosphates. zinc. nickel and iron must be removed. This is done by passing through a 10 mi column.
Lithotamnium Calcareum, 1.8 m in diameter and 4 m in height, with an effluent flow of 2 m3 / hour and with a particle size between 0.2 'and 4 mm.

The process provides the following decontamination results
Content in ppm Content in ppm
before treatment after treatment
Iron 25 1
Nickel 24 2
Zinc 55 0.3
Phosphate 72r 42
Titanium 12 4 Manganese 1 7
The capacity of the product to carry out a simultaneous decontamination of six components is noted.

EXAMPLE 2 Installation for surface treatment before paints using amorphous phosphating agents.

Using an installation comprising a 10 m3 column of
Lithotamnium Calcareum screened, dried, with a particle size between 0.2 and 4 mm, having the following dimensions: 1.8 mm in diameter and 4 m in height. The effluent is passed through this installation with a flow of 5 m3 / hour.

Content in ppm Content in ppm
before treatment after treatment
Phosphate 430 32
Iron 48
Molybdenum 1
Titanium 8 EXAMPLE 3 Anodizing installation
The anodization of aluminum requires for cold sealing operatlorlr the use of nickel fluoride as well as phosphates and sulfates. In order to purify the water resulting from this manufacturing process, a column is used of 10 m3 of Lithotan'iniurn
Calcareum with the following dimensions 1.80 m in diameter and 4 m in height. the passage of the effluent @effectuant with a flow of 10 rr-l- .Hour. The particle size of Lithotamnium Calcareum is between 0.1 mm and @ mm.

The decontamination results obtained. are the following
Content in ppm Content in ppm
before treatment sprés treatment
Phosphate 80
Nickel 3.5
Fluoride 25
Sulfate 10
EXAMPLE 4: Purification unit in the food industry
In the brewery, many products are used for industrial hygiene. These after use are present in the effluents so do we find phosphate and iodide ions. as well as small amounts of copper therein.

The brewery effluents resulting from the cleaning processes pass over a 5 m3 column of dried screened Lithotamnium Calcareum, the dimensions of which are as follows. 1.90 m in diameter and
1.90 m high. The grain size is. between 0.2 mm and 10 mm
The flow of the effluent is carried out with a flow of 5 m3 per hour. The following results are obtained
Content in ppm Content in ppm
before treatment after treatment
Phosphate 250 30
Copper 3 0.5 lodure 14 1
EXAMPLE 5 Processing unit in industry using radio-elements
In laboratories performing radio immunological analyzes, many elements are used in very small quantities such as cadmium, cesium. ruthenium. molgbdenum, indium, cobalt. The water from the laboratory is decontaminated on a column of 1 m3-. of Lithotammum Calcareum having a dimension of 0.8 m in diameter and 2 m in height. The gr @ nulometry of Lithoth @ mmun
Caloareum is 0.1 @ 2 mm The flow rate for effluents is
O 1 m3 hour
The efficiency results of the process are as follows:
Detection is carried out before passage After evaporation the dry matter gives to the pulse counter in one derm minute 13215 after @ passage in the column a sample of the same volume given in half a minute to the pulse counter 185.

Claims (3)

 1- Process for the purification of industrial effluents characterized by the passage of these industrial effluents through a column of Screened and dried Lithotamnium Calcareum. having a particle size between 10 mm and 0.1 mm. Industrial effluent which may contain one or more of the following nickel ions. zinc, copper, cadmium. iron. indium, manganese, molybdenum, cobalt, ruthenium, titanium, phosphate. sulfate, fluoride, iodide, cesium.  2- Purification process according to claim 1 characterized in that the Lithotamnium Calcareum screens, dried, and preferably has a particle size between 0.5 mm and 2 mm.  3-Purification process according to claims 1 and 2, Characterization in that the passage of the effluents is carried out in a column filled with screened Lithotamnium Calcareum. dried, whose dimensions of 1 column are such that the dismetre is at most equal to the height.