DE2344587A1 - SEWAGE TREATMENT PROCESS - Google Patents

Description

Priority: September 4, 1972, Japan, No. 87 960

"Wastewater Treatment Process"

The invention relates to a waste water treatment method.

The invention relates in particular to a waste water treatment method, using developed tissue from plants. It thus relates to a method for cleaning of sewage, which consists in having the sewage with Cells of a fully developed tissue of a plant in contact brings, whereby the contaminants contained in the wastewater from the developed tissue cells of the Plant are absorbed and the fully developed tissue cells are separated from the wastewater.

With the evolving industry have come in considerable Dimensions also result in damage from industrial wastewater.

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In particular, sewage containing various toxic substances and contaminants such as heavy metals such as cadmium and mercury used in agriculture Chemicals, oils, organisms, chemicals, synthetic detergents and dyes containing from factories in the public sewers are drained, which poses considerable dangers for people, 'who live in certain areas.

To prevent the damage caused by sewage Various wastewater treatment methods have been proposed and also used, but with regard to the Efficiency, the necessary costs for the devices, the operating costs, the maintenance of operations and the like raise problems so that it can be determined that no satisfactory process has been developed.

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Usual wastewater treatment methods may vary depending on which Wastewater types are treated, divided into physical, chemical and biological processes, being for Various improvements have been proposed and widely used for each practice.

- At the moment the biological process is predominantly used, Since the most diverse types of waste water can be treated, no addition of chemicals and the like is required is, and the running costs are relatively low, so that is assumed can be that this processing method for the future looks promising.

The biological process is of two types, i.e., a process involving oxidative decomposition by aerobic microbes while the other method involves fermentation by anaerobic microorganisms, the former method includes the activated sludge process and

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and the trickling filter process, while the methane fermentation process represents a typical representative of the latter process.

As in the biological process, the removal of the toxic Contamination occurs through the metabolism of microorganisms, it is necessary that the microorganisms used have sufficient resistance to the toxic substances to be removed.

As a result, there are considerable difficulties in the adaptation of microorganisms to the sewage and maintenance good treatment conditions, so that in the practice of biological processes sophisticated techniques and Knowledge is required.

In particular, heavy metals, such as mercury and cadmium, unfold even when they are in small quantities in the wastewater contain extremely toxic effects on the microorganisms. As a result, it is extremely difficult to find heavy metals To treat wastewater in large quantities, it often occurs that treatment devices that are below satisfactory Conditions that could be kept in operation are significantly disrupted by the introduction of heavy metals.

If synthetic detergents or detergents are still in the wastewater to be treated is contained, 'the metabolism of microorganisms due to the presence of large quantities inhibited from bubbles, so that the treatment conditions are deteriorated. On top of that, it is well known that significant damage occurs when synthetic detergents are introduced into wastewater.

The biological processes currently in use result in a number of disorders caused by various factors with the resulting problems

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and the causes of which are not fully known, so that no satisfactory countermeasures are developed either could. As a result, the number of types of wastewater that can be treated with biological processes is significant restricted.

A method for removing heavy metals has been proposed which consists in that one special Bacterial species that are resistant to a heavy metal are separated and released into wastewater containing this heavy metal breeds.

As an example of such a method, there can be mentioned a method for removing mercury that is contained therein consists in that one species of bacteria belonging to the species Pseudomonas in an aqueous solution containing mercury breeds. /.

However, these properties of the microorganisms are specific for certain metals and are significantly influenced by the metabolism of the microorganisms. Accordingly, it is believed that this activity differs significantly among the different strains, even taking into account that they belong to the same species. Further, the wastewater treatment is performed in many cases in the presence of many other microorganisms and impurities _t so that a significant probability exists that the growth of the desired species is inhibited by these microorganisms and impurities. Accordingly, it is questionable whether the desired heavy metal can be effectively removed by using such a method.

Furthermore, it is when using the usual biological processes difficult to remove dyes that stain the rivers and create an undesirable appearance.

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From the above it can be seen that various effluents cannot be effectively processed using conventional biological methods, so that development a wastewater treatment process with which such wastewater can be treated has become necessary is.

It is therefore an essential object of the invention to provide a waste water treatment method provide by the above with regard to the usual wastewater treatment methods specified problems solved and dealt with the toxic substances and impurities in a simple manner with high efficiency and can be removed with ease of operation without the risk of other contaminants to be introduced.

This goal can be achieved by the method according to the invention which consists in the fact that waste water containing various toxic substances and impurities, such as heavy metals, Contains dyes and synthetic detergents or detergents, with cells of a finished tissue of a seed plant brings into contact, whereby these toxic substances and impurities are adsorbed on the cells, whereupon the cells are separated from the waste water.

Further objects, objects and embodiments of the invention will become apparent from the following description and the attached Drawings.

Figures 1 and 2 represent the invention in a schematic manner Wastewater treatment is a column 1, which is with the cells of a fully developed tissue of a seed plant is filled, a container 2 in which the waste water is brought into contact with these cells, a stirring device and a separator 4 are provided.

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As stated above, common wastewater treatment methods exist various problems and the number of types of wastewater treated by this method can, »is severely restricted.

Since the physico-chemical properties of the cell surface in different plants do not differ significantly. " it is assumed that with the physico-chemical adsorption of toxic substances, such as heavy metals, on the surface, of plant cells or inside these cells, there is no great difference in terms of the adsorption properties is given in different plant species. If, therefore, plants have strong ion exchange properties with respect to heavy metals or have a large adsorptive capacity and which are not harmful to humans are collected, in a form suitable for wastewater treatment treatment and for adsorption of contained in the wastewater Heavy metals are used and then separated from the waste water, the target heavy metals become light removed and there is no need to be particularly careful about the various difficulties that may arise in common biological processes, such as inhibition the growth due to heavy metals, the difficulty of the pure culture of the bacteria and the operating conditions. That the same applies to other contaminants such as synthetic detergents and dyes.

For example, plant cells and plant fibers are effectively stained by basic dyes and direct dyes, see above hence it can be assumed that dyes can be effectively removed by applying them to plant cells adsorbed.

Similarly, due to the fact that surface-active Agents such as alkylbenzenesulfonates and alkylsulfates

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show strong affinity for celluloses, the constituents of ■ Plant cells represent believed to be synthetic detergents by using plant cells as adsorbents can be removed from sewage.

According to the invention, cells of a fully developed tissue are used a seed plant as such plant cell adsorbents for removing the various contaminants from waste water used.

The plant cells to be used according to the invention are more precise , Tissue cells from seed plants, i.e. higher plants whose growth is complete, namely cells from finished plants Tissues from seed plants. According to the invention, stems and stems as well as seeds from annuals and biennials are more precise Plants used. The following are fully developed tissue cells from seed plants which are produced according to the invention can be used, described in more detail.

Seed plants include stems and stems, roots and leaves and belong to the group of stem plants in which there are paser vascular bundles form. They represent highly developed plants of considerable size found in the entire world in the countryside grow and which are widely used by humans and have a significant impact on human life exercise. It is well known that engineered fabrics, which arise as a result of the aging of the tissue cells of these seed plants, porous and extremely permeable to water are. Cells that build up such fully developed tissues are in many cases transformed into parenchymal tissues that contain the The bark system of trees or the stems of Gramineae (grasses) form fibrous tissue which form the trunks of the trees or sclerenchymal tissue which is made up of cells with enlarged and hardened cell walls are built up. The plant tissues are believed to be the fiber tissues for the

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human life offer the greatest benefit, so these fabrics are widely used for pulp and paper, building materials and the like have been applied. It is generally believed that parenchymal tissues are of little value. Sawdust or sawdust and waste produced during the cutting and sawing of trees, which are widely considered to be Building materials for furniture and as fuel can be used. . den, ais is the cedar, the oak (lilac), the larch, the cypress, the noble fir, the silver fir, the Himalayan cedar, the Chinese black pine, the lauan tree, the tung tree, the Japanese cypress, the ginkgo tree, the pine or the pine, the Mangnolia hypoleuea, the ZeI-kova tree, the cherry tree, the walnut tree, the camphor tree, persimmon wood, the pasania tree, the Japanese oak, Quercus serrata and the like are discarded as wastes of no practical value, albeit some of these materials be used for the production of activated carbon or the like.

As far as agriculture is concerned, it can be said that parenchymal tissues, like the stalks left after collecting the seeds, potatoes or sweet potatoes as animal feed and used for composting, but there would be significant benefits to farmers if more valuable Uses could be developed.

As stalks of agricultural products that are formed in large quantities and that remain after harvest, the stalks of rice plants, barley, wheat, soybeans, red beans, corn, buckwheat, sugar cane and the like may be mentioned. In addition, you can cut branches and trunks from cut trees, such as unhooked materials, peach trees, deciduous trees, Mention roses and the like. Furthermore, grasses growing in fields and in the mountains, the parenchymal tissue containing stems, like goosefoot grass, develop Japanese Pampas grass, ramie, mugwort, glycine and the like

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used accordingly.

The fully developed tissue cells of the named seed plants adsorb heavy metals, dyes, synthetic detergents and other contaminants that are contained in aqueous solutions and are therefore according to the invention used with advantage.

Young cells of meristem tissues of seed plants can also effectively remove heavy metals, dyes, synthetic detergents and the like adsorb, but are not suitable for practical use because they may be ground during treatment and the cell contents will leak out easily. On the other hand, fallen leaves can from trees, as well as the finished tissues that make up the trunks or stems, adsorb heavy metals and the like and do not suffer from the disadvantage that the cell contents of the leaves leak out during the treatment. Accordingly, these materials are suitable for the present invention.

As already mentioned above, the invention relates to the separation of various toxic substances and impurities, such as heavy metals, dyes, synthetic detergents and the like. From aqueous solutions, in particular from various Industrial wastewater, the disposal of which poses a significant social problem, by using these substances absorbed on materials that have not been used or have not been used effectively so far. As a result, according to the present invention, a considerable achieve technical progress.

Treatment of wastewater with the cells of a finished product Tissue of a seed plant can be done in different ways. As can be seen from the attached Figure 1, the wastewater is fed via one end into a column filled with the fully developed tissue cells of a seed plant

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while the treated water is withdrawn from the other end of the column.

From der'Figur 2 a method can be seen which consists in bringing the waste water to a sufficient extent with the fully developed tissue cells of a seed plant in a container 2 equipped with a stirrer 3, whereupon the mixture is poured into a Introduces a pesticide / liquid separator 4 in which the cells are separated from the wastewater and then the treated water is withdrawn. As a solid / liquid separator ² J you can use not only a conventional filter, but also various other separating devices that are usually used in wastewater treatment,

The following examples are intended to explain the invention further. but without restricting them.

example

This example illustrates an embodiment according to which metals contained in an aqueous solution are used removed from a column filled with crushed Japanese cypress wood.

First, the wood of a fully grown Japanese cypress was sawn to make sawdust (a powder with a grain size of several tens to several hundred, u). The sawdust was washed well with water, whereupon 100 g (dry basis) of the material were filled into a glass column with a diameter of 30 mm and a length of 650 mm. Then were 300 ml of an aqueous solution containing 500 ppm of one in the the following table I contained metal, by the Column, whereupon the column with pure water (about 1500 ml) was washed. The metal concentration of the total effluent

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was determined by the atomic absorption method and it became also determines the amount of metal absorbed by the wood powder and the metal separation ratio, which in in Table I below is calculated.

As can be seen from the results given in Table I below, Al, cations of metals with an atomic number of at least 24, such as Cr ^ ⁺ , Mn, Co, Ni ² *, Cu ²⁺ , Zn ²⁺ , Ag ⁺ , Cd ²⁺ , Hg ²⁺ and Pb ²⁺ and organic mercury compounds such as phenyl mercury acetate can be removed with a high separation ratio of about 80 to 100 %.

TABLE I.

Metal compound separation ratio

Al (NO ₃ ) ₃ 40 9816/07 4 4 97 CrCl ₃ 80 MnSO _{1 y} 84 CoSO ₁₁ 86 NiCl ₂ 81 CuSO ₁ J 98 ZnCl ₂ 92 AgNO ₃ > 99.9 CdCl ₂ > 99.9 HgCl ₂ > 99.9 Phenyl mercury acetate > 99.9 Pb (NO ₃ ) ₂ > 99.9

example

This example explains an embodiment according to the invention

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form, according to the Hg using the column method different wood powder is removed.

In the same way as described in Example 1, powder samples of lilac, cedar, lauan, ginkgo wood, the wood of Magnolia hypoleuca and walnut wood were produced. These powders were placed in a column, whereupon 300 ml of an aqueous solution containing HgCl ₀ at a concentration of 500 ppm,

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calculated as Hg contained, were passed through the column. In the same way as described in Example 1 was the

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Hg concentration in the effluent is determined and the Hg separation ratio is calculated. In each case the separation ratio was higher than 99 »9%, with no noticeable difference due to the particular wood used.

Example 3

2 + This example illustrates an embodiment according to Cd by. Using a batch process using zelkova wood.

Sawdust was produced by sawing Zelkova wood, of which 10 g (dry weight) was added to 1 liter of an aqueous solution containing CdCl ₀ in a concentration of 10 ppm,

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calculated as Cd, whereupon the mixture was stirred for 15 minutes at room temperature. Then the wood powder removed using a paper filter and the

Cd concentration determined by atomic absorption spectrometry. It was found that 85 % of the Cd was removed.

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Example 4

This example illustrates an embodiment according to which

Cd is removed by using rice straw, wheat straw and corn stalks as adsorbents.

Rice or wheat straw or corn stalks obtained after threshing or harvesting were finely cut, ground with a mill (to a grain size of about 500 µ) and washed with water. Then 20 g (dry weight) of the powder were added to 1 liter of an aqueous solution containing CdCl ₂ in a concentration of 10 ppm, calculated as Cd ²⁺ , whereupon the mixture was stirred for 20 minutes at room temperature. Then the powder was removed using a filter paper and the Cd ²⁺ concentration in the filtrate was determined by atomic absorption spectrometry. As a result, it was found that Cd was removed from rice straw, wheat straw and corn stalks at a separation ratio of 91% » 91 % and 93 %, respectively.

example

This example illustrates one embodiment of the invention, according to which dyes using the batchwise approach Process using cedar powder as an adsorbent.

A powder was prepared by sawing cedar wood, which was sufficiently washed with water. Then 10 g (Trockengewichi;) of the cedar powder to 100 ml of an aqueous Solution added containing a dye indicated in the following Table II, whereupon the mixture for 1 hour Room temperature was stirred. Then the wood powder was removed using a filter paper, the amount of in the aqueous solution contained in the dissolved state dye

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is determined and the amount of dye removed is calculated. As a measure of the paraffin concentration, the extinction (Emax) pel of the maximum absorption in the first absorption band in the visible range was determined (cuvette thickness 1 cm). The results obtained are summarized in Table II below.

It can be seen from these results that basic dyes were removed with one exception having a separation ratio greater than 95% and that the separation ratio obtained in the case of the direct dyes was lower than that of the basic dyes, but about
half of the investigated direct dyes could be removed with a separation ratio of over 80 %.

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TABLE II

Dyes

Emax

Initially treated solution solution

Separation ratio

Basic dyes

Crystal violet 26.0 0.47 98.2 Brilliant green 33.0 0.63 98.1 Methyl violet 56.0 1.40 97.5 Acridine orange 33.6 1.01 97.0 Methylene blue 31.2 1.03 96.7 basic fuchsin 39.5 1.58 96.0 Safranin T 2.4.8 0.99 96.0 Rhodamine 6G 37.0 1.81 95.1 Rhodamine B 36.0 1.08 70.0

Direct dyes

Brilliant dianil green 36.5 0.99 97.3 Niagara Sky Blue 6B 31.0 2.14 93.1 Chrysamine G. 34.8 5.30 84.8 Direct Fast Yellow GC 35.3 5.90 83.3 Chrysophenine 37.0 6.90 81.4 Congo red 38.5 8.50 77.9 Direct Coupling Orange 26.4 6.60 75.0 Direct Scarlet B 33.1 14.0 57.7 Direct Blue 2B 39.2 17.0 56.6 Direct Pure Yellow 53 30.2 17.5 42.0

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Example

This example illustrates an embodiment of the present invention in which methylene blue is removed by the column method was ,, where lauan wood, lilac wood, Magnolia hypoleuca, Zelkova wood and cherry wood are used became.

100 g (dry weight) of the wood powder prepared according to Example 1 were introduced into a column with a diameter of 30 mm and a length of 65O mm, whereupon 100 ml of an aqueous solution of methylene blue (Emax = 280) were passed through the column. Due to the different nature of the wood powder used as the adsorbent, there was no noticeable difference in the adsorption properties. In each case, the dye on an area of 8 to _t 10 cm from the beginning column downwardly extended was adsorbed. Even when the column in which the dye was absorbed was washed with a large amount of water, the dye was not desorbed. Thus, methylene blue was completely adsorbed and eliminated by the wood used as the adsorbent.

example

This example illustrates an embodiment of the invention employing Methyl Violet and Niagara Sky Blue 6B of the batch process using torreya wood as an adsorbent.

A dead torreya tree that had lost its green color was finely cut up and using a Mill to a grain size of about 500, grind. Then were 15 g (dry weight) of the powder obtained in this way to 100 ml of an aqueous solution containing methyl violet (Emax = 56.0)

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or Niagara Sky Blue 6B (Emax = 31 »0) was added and the mixture was stirred at room temperature for 1 hour. The Torreya wood powder was then filtered off and the extinction of the dye remaining in the filtrate was determined. It was found that the extinction in the case of the methyl violet was 1.25 and in the case of the Niagara Sky Blue 6B 1.32, so that separation ratios of 9798 % and 95 » 7 % were obtained.

Example 8

This example illustrates an embodiment of the invention, according to the synthetic neutral detergents, namely dodecylbenzenesulfonate (DBS) and sodium dodecylsulfate (SDS) by using powders of cedar wood, spruce wood, the wood of the Japanese cypress, lauan wood, the wood of the Magnolia hypoleuca, Zelkova wood, walnut wood, persimmon wood, Oak wood and the wood of Quercus serrata should be removed.

10 g (dry weight) of the wood powder produced according to Example 1 were added to 100 ml of an aqueous solution containing 50000 ppm DBS or SDS, whereupon the mixture was stirred for 1 hour. stirred at room temperature / The wood powder was filtered off and the concentration of that contained in the treated solution Detergent was determined as follows.

2 ml of the DBS or SDS-containing solution and 0.2 ml of a concentrated solution of methylene blue were added to 8 ml of chloroform added, after which the mixture was shaken vigorously, with the neutral detergent such as DBS or SDS a 1: 1 complex formed with methylene blue which migrated into the chloroform layer. By determining the absorbance of the complex in the Chloroform layer, the concentration of the neutral detergent contained in the treated solution can be determined.

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The separation ratios of the detergents DBS and SDS using the respective wood powders are as follows Table III given. Due to the fact that the grain size of the different woods was different, will assumed that there is no significant difference between the woods in terms of adsorption properties. With any wood powder, the synthetic detergents could be removed effectively.

TABLE III

Wood separation ratio

DBS SDS - cedar 94 89 Spruce 91 89 japanese cypress 93 90 Lauan wood 95 91 Magnolia hypoleuca 95 89 Zelkova wood 92 95 Walnut wood 94 88 Persimmon wood 88 90 Oak 92 93 Quercus serrata 92 91

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Examples of heavy metals that can be separated by the process according to the invention are: Al, Cr, Mn, Co, Ni, Cu, Zn, Ag, Cd, Hg and / or Pb.

Examples of dyes that can be separated by the process according to the invention are basic dyes and direct dyes, especially crystal violet, brilliant green, Methyl violet, acridine orange, methylene blue, basic fuchsine, safranine T, rhodamine 6G, rhodamine B, brilliant dianil green, Niagara Cloud Blue 6B, Chrysamine G, Direct Fast Yellow GC, Chrysophenin, Congo Red, Direct Coupling Orange, Direct Purple B, Direct blue 2B and / or direct pure yellow 5G.

Claims

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Claims (3)

Claims 1 ^ / Biological wastewater treatment process with the help of Microorganisms, thereby denoted lehnet ", that he (a) brings the wastewater into contact with fully developed tissue cells of a seed plant, and this mixture, if appropriate stirs, whereby the substance to be removed from the wastewater, especially heavy metals, dyes and synthetic detergents are adsorbed onto the developed tissue cells, and (b) separating the fully developed tissue cells, on which the substances mentioned are adsorbed, from the waste water. 2. The method according to claim 1, characterized in that the finished developed tissue cells Cells from fully developed tissues of wood and / or trunks and stems of annual and biennial plants used. 3. Wastewater treatment method according to claim 1 or 2, characterized in that one for the step ORIGINAL INSPECTED 409816/0744 2344387 (a) a tubular column open at both ends used and in the stage (b) introduces wastewater into the column at one end and the treated wastewater at the other end of the column withdraws. ORIGINAL INSPECTED 409816/0744 Blank page