JPS6014983A - Method for removing and recovering metal by using root part of water hyacinth - Google Patents

Abstract

PURPOSE:To remove the metals in water efficiently and to recover the metals bringing drainage water, waste water and natural water contg. metals into contact with the root part of water hyacinth (eichhornia crassipes solms) then treating the root part of the water hyacinth with a dilute acid soln. CONSTITUTION:The root part of water hyacinth is used in the state of the selected moist root or after the root is thoroughly drained of water, the root is dried by ordinary natural drying or by drying with ventilated heating to form the dry root having about 10% moisture. A plastic net bag in which the root of the water hyacinth prepd. in the above-mentioned way is packed is charged into drainage water contg. metals. The bag is left to stand for a while and if necessary the water is stirred during this time to adsorb the metals in the water on the root part and thereafter the net bag packed therein with the root part is taken out. The root part is then washed with 0.1N hydrochloric acid soln. to liberate the adsorbed metals from the root part and to recover the same. The root part is washed to nearly neutral with water to regenerate the same and is reused for the adsorption and removal of the metals.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for removing and recovering metals from wastewater, wastewater, and natural water by using the root part of the water hyacinth, which is a mainstay of lakes and rivers. It is hated as a miscellaneous violet because it overwhelms lakes, marshes, rivers, and blocks waterways. However, in recent years, from the viewpoint of effective use of unused resources, the leaves and stalks of water hyacinth have been considered for use as feed for livestock, but the effective use of the roots has not yet been opened. Furthermore, it is known that the growing water hyacinth adsorbs heavy metals from industrial wastewater9, and this is considered to be a physiological function of the water hyacinth, which uses this function to remove heavy metals from the industrial wastewater. However, some of the adsorbed metal also migrates to the first leaf and the first petiole, so it was a problem to use the first leaf and the first petiole as feed. (Kazunori Toyama, Hiroshi Eyo, Takefumi Yamagishi, Weed Research, Volume 22, No. 3, 27.19'7) As mentioned above, the roots of the growing water hyacinth are used as waste water as part of the plant's activities. It was known to absorb entire stations such as. The present inventors conducted various studies on the mechanisms by which the roots of the water hyacinth absorb metals, and found that the roots of the hyacinth were cut off from the root aperture and petiole, and the roots were separated, and the plant ceased to function as a plant. After setting it to that state.

It was discovered that even if the product was placed in water containing metal salts and left unattended, it would still sufficiently absorb metals. Based on this fact, the present inventors further inferred that the metal absorption effect of the roots of the water hyacinth is not simply a physiological effect of the phytophyllum (but rather a chemical function of the tissue components of the root). After separating the root part of the water hyacinth and thoroughly drying it, we put it into water containing metals, and found that even the dry form did not have sufficient ability to adsorb metals, and the ability was almost the same as that of the wet form. This seems to have made it even clearer that the metal adsorption function of the roots is based on the chemical functions of the root tissue components.

In recent years, when discharging various types of wastewater and discharged water into public river areas, it has become a legal requirement to reduce the concentration of metals contained in this water to below a certain standard amount. At the same time as it is desired to develop a method for eliminating office work,
c. It is also desirable to recover the removed metals so that the environment cannot be recontaminated with the metals.

Based on the above-mentioned viewpoint, the present invention has developed a technology to efficiently remove metals contained in various industrial wastewater, wastewater, and natural water by utilizing the metal adsorption functionality of the roots of water hyacinth. In the present invention, fully grown leaves and petioles are separated, and these are distributed to uses such as feed. The collected roots are used as follows: roots (il
Dry the separated wet material directly or by an appropriate method, that is, shake off the water and dry it by general sun drying or ventilation heating drying to reduce the moisture content to 1.
It should be around 0%.

2. Dried plant that does not deteriorate when the root is preserved.
Used in Class 1 condition.

Two operations are used to adsorb and remove gold 8 by bringing these roots S into contact with metal-containing water. The first method is the batch method, in which the roots are placed in water containing metals, left for a while, and if necessary, the water is stirred by an appropriate means to allow the roots to adsorb the metals in the water, and then the roots are taken out. In this operation, the liquid is packed in a plastic net bag of appropriate size, and the bag is put into or taken out of the water.This operation is based on a chromatographic method. , this is done by filling the roots of a pipe of appropriate size, and then flowing water containing metals, which had been previously stored in a storage tank or storage tank, into the pipe with a liquid feed pump, and then flowing it to the roots of the back. It adsorbs metals in the water and transfers the drained water to a separate storage tank. In addition, water such as waste water and wastewater is generally held in storage tanks11.Therefore, several storage tanks are connected with pipes of appropriate size, and the roots are placed in these pipes. Water is moved between the tanks in one direction through this tube, and the whole eggs in the water are adsorbed to the roots in the tube. The roots can be compressed into a filter pad shape that can fit into the tube, and can be used by forming the required number of pads into a β shape and keeping them in the tube. In order to form a pad, the dried material may be used as it is, or it may be cut into a shape of an appropriate size and then compressed appropriately and used as a shape retaining material.

Next, the roots that have adsorbed metal to almost a saturated level by the batch method or chromatographic method described above are washed with a dilute acid solution of an appropriate concentration, such as OIN hydrochloric acid solution, and the adsorbed metals are washed with an acid solution. It is exchanged with hydrogen ions and released from the roots, eluted into a dilute acid solution and recovered. The roots are then regenerated by washing with water and almost neutral P.
The reuse of the root part of the wax, which can be used for adsorption and removal of metals, is possible until the root part deteriorates and becomes unusable. It decreases by 10 to 15% after one regeneration, and decreases somewhat after subsequent reuse.
This can be accomplished by placing the root in a tank of dilute acid solution and leaving it for a few minutes, or by pouring an appropriate amount of dilute acid solution while the root is still in the tube used previously.

As mentioned above, Mizumoto f! In A, the leaves and petioles of water hyacinth are necessary for the adsorption and removal of metals in various types of water (because only the roots are used, the first leaf and petiole are separated in advance and used as feed, etc.). C. The roots of the water hyacinth can be used to take advantage of the characteristics of each part of the water hyacinth.Since the root part of the hyacinth hyacinth is used as something that was previously discarded, it has the advantage of being very economical and can be used at a very low price. There is.

When using the roots, the effect of moistening one plant is that it can be used during high temperature periods or high temperatures when water hyacinth multiplies.
In the ML region, roots are readily available and can be used as is as a metal adsorbent in water.On the other hand, the effect of using dried roots is that they are easier to transport and handle, and have lower It can be used year round in any location as it retains moisture and can be used year-round.It can also be used by leaving the roots as they are or cutting them off to create a filter pad of the desired shape. I can do it, etc.

The present invention, which utilizes the roots, is extremely effective.

For the removal and recovery of industrial wastewater, waste water, and metals such as Tendai, it is used in areas where a technology that is as simple to operate as possible and that is as affordable as possible is required.

The present invention, which uses the roots of water hyacinth, can be expected to be very effective.On the other hand, since the metals adsorbed to the roots can be easily recovered with a dilute acid solution, useful metals can be concentrated and used for decay. It also has the advantage of being able to recover harmful gold MVi and dispose of it as an appropriate waste object. 1fLvc of lead 110PP solution.

Dry roots of water hyacinth T66 were added and while stirring, the decrease in lead in the solution was measured. If no reduction was observed, the gfl and lead were poured into a solution of 110 PP and the reduction was measured. This operation was repeated 5 times. The results were as follows.

Example 2 "Adsorption of lead by a batch method using the wet roots of water hyacinth" A solution of lead 110PP in which lead acetate was dissolved 17. f. Wet roots of water hyacinth [309] were added, and while stirring, the decrease in lead in the solution was measured. When no reduction was observed, the roots were placed back into a new lead 110PP solution IL and the reduction was measured.

This operation was repeated 5 times, and the results were as follows.

Example 3 "Adsorption of lead, copper, and cadmium by column method using dried roots of water hyacinth" A column with a length of 2 mm and 5 nm was prepared by filling a glass tube with an inner diameter of 15 mm with 2.79 dried roots of water hyacinth. . Add 10 l each of lead, copper, and cadmium to this column.
The solution containing PP was flowed at a flow rate of 100 − for 1 hour using a peristaltic pump. Saturation of the hammer adsorbed to the root of Karajinchu 1
[Ha]-26711] Copper 16 Cadmium 10 Qq.

Implementation Rejuvenation ``Recovery of adsorbed metals from the roots that have adsorbed metals using dilute acid?l! and regeneration of the adsorption capacity of the roots'' Dry roots of water hyacinth 2. A lead-containing solution was poured into a column made using Ma9, and the lead was adsorbed to the saturation point (adsorption amount was 126 -). After that, 200 K of Ic&O, 1N hydrochloric acid was passed through the column to recover the adsorbed lead. The 0 recovery rate was 12h65L of lead-containing liquid (1oPPm) that was injected into the mouth was about 100 g, and was recovered with a dilute acid solution of 2oo@i, so the concentration rate was about 60 times. After introducing 20o1 of water to remove the dilute acid solution, 110PP of lead-containing solution was poured again, and the saturation of the adsorbed lead was 108m7.
It was 85% of the first saturated sound. This means that the regeneration rate of adsorption capacity is 85%, and reuse is possible.

Patent applicant Director General, Food Research Institute, Ministry of Agriculture, Forestry and Fisheries (Procedural amendment September 22, 1980 Commissioner of the Japan Patent Office Kazuo Wakasugi?, person making the amendment 4 Agents subject to amendment Detailed explanation of the invention column t, amendment Content (1), in line 17 of the second page of Meisho I Tetsu, ``Shitere is hated.'' has been corrected to ``Shitere is hated.''

(2), In the details @ page 2, line 19, "Tobu and Sarabe wa" was corrected to "Tobu and Zoumibe wa =".

(8) "Leaf plate part -" in line 6 of whistle on page 3 of 1 specification is corrected as "petiole part -1~";"Mpart" in line 1 of the same page is corrected as "surname part" on the same page. In line 16, "Kurobe and Ha U part" was corrected to "Mitsube and Ha U part".

(4), page 5, line 4 of the specification, “Eastern and Yeh tribes---”
was corrected to "Tobu and Hazubu."

(5) Deleted the ``used before'' in the 12th line of page 1 of the specification.

(6), “petiole” in the details page @ lines 16 and 18
was corrected as "petiole".

Patent applicant: Shinzo Nagatsumura, Food Research Institute, Ministry of Agriculture, Forestry and Fisheries ,,j−j；7゜ Representative Patent Attorney Ryosuke Tsutsumi・・・・ 1. 1

Claims (1)

[Scope of Claims] (1) Removal of metals using the roots of the water hyacinth, characterized by bringing the roots of the water hyacinth into contact with wastewater, waste water, and natural water containing metals to remove metals from water. Law. (2) A method for removing metals according to claim 1, F, which uses a dried root of the water hyacinth. (8) Claim 1, which uses a wet root of the water hyacinth. Removal of metals as described in claim 1, characterized in that (4) the roots of the water hyacinth are put into waste water, wastewater or natural water containing metals, and left to stand or stirred. Law. (5) The method for removing metals according to claim 1, which comprises flowing waste water, waste water, and natural water containing metals through a pipe filled with the roots of water hyacinth. (6) By treating the roots of the water hyacinth that have adsorbed metals with a diluted acid solution, the adsorbed metals are released and recovered from the roots of the water hyacinth, and the roots are washed with water with a claw and then reused. Claims 1 to 5
Method for removing metals as described in section.