JP2008214600A - Heavy metal disposal material and soil improvement agent to reduce and remove heavy metal and food waste water, and heavy metal removal method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide microorganisms for the disposal of the heavy metal in soil and waste liquid. <P>SOLUTION: This method comprises the disposal in the soil and of the waste liquid and the disposal of the heavy metal to carry Bacillus natto and Actinomyces. Heavy metals include lead, cadmium, copper, iron, chromium, zinc, nickel, boron, and sodium. An example of Bacillus natto is a fungus of Bacillus subtilis. The disposal of the heavy metal using these useful microorganisms economically advantageously allows heavy metal disposal and soil improvement by mixture and agitation in this place to create an environment in which useful fungi can suitably proliferate without the need for an enormous cost and a maintenance expense. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to an environmental purification technique for reducing and removing heavy metals in soil and waste liquid.

Heavy metals other than sodium, an alkali metal, are very hard and have an melting point of 1,000 ° C. or higher and a boiling point of 1,000 ° C. or higher. Some of them have semiconducting properties and correspond to metalloid elements. is there.
If a large amount of heavy metals is ingested by humans or livestock, there is a decrease in blood pressure, shock symptoms, and respiratory arrest due to central nerve suppression, and chronic poisoning causes anorexia, vomiting, and skin symptoms.
Based on these chemical properties, “Boron and its compounds” were added in July 2001 when the Water Pollution Control Act was partially revised and scheduled to be implemented in July 2007. As for the standard value so far, the emission limit value was 500 mg / l, but after the revision it became 10 mg / l, and the environmental standard value became 1 mg / l.
Further, cadmium is regulated to have an environmental standard value of 0.01 mg / l and a drainage standard value of 0.1 mg / l.
Furthermore, according to the distribution standard value of the Food Agency, distribution is prohibited as food at 0.4 mg / l or more.
To construct a 100 m ³ / yen processing facility that satisfies them, construction costs are approximately 100 million yen, and maintenance costs are approximately 20 million yen per year.
In view of this, the present inventor has developed a simpler and less expensive heavy metal treatment method, and in Patent Document 1, discloses a technique relating to an animal breeding flooring material that does not decompose and deodorize ammonia and the like.

  Japanese Patent No. 3561593

If soil is contaminated from wastewater containing heavy metals, it may affect human health by directly ingesting the contaminated soil or drinking groundwater in which harmful substances are dissolved from the contaminated soil. There is.
Such soil contamination has been rarely clarified until now, but in recent years, with the redevelopment of industrial sites and the like of companies, soil contamination due to heavy metals, volatile organic compounds, etc. has become apparent. In particular, the recent increase in the number of known cases of contamination has been significant, and the number of newly discovered cases of soil contamination over the past few years has been a high level, which has also been an issue for public health safety.

In the food processing industry, since rock salt is used in production processes such as kimchi pickles and umeboshi, trace amounts of heavy metals and sodium are contained in the rock salt. As the wastewater permeates into the groundwater, the amount of heavy metals and sodium contained in the groundwater of 0.01 ppm or more has a risk of affecting human safety.

The problem to be solved by the present invention is to establish a soil conditioner and heavy metal treatment technology using microorganisms that reduce and remove heavy metals in soil and waste liquid.

The heavy metal processing technology using the microorganism of the present invention is characterized in that wood chips, soil, rice husks, and incinerated ash are loaded with Bacillus subtilis and actinomycetes.

In the method for reducing and removing heavy metals according to the present invention, the concentration of heavy metals including sodium is reduced by decomposing and reducing natto bacteria (including Bacillus subtilis) and actinomycetes in the soil and in aqueous solutions. It is characterized by that.

The inventor has selected and combined natto and actinomycetes, and found that the kimchi waste liquid containing a large amount of heavy metals is decomposed and extinguished among the food waste liquids, resulting in the present invention.
In other words, it has become clear that, in Bacillus natto and Actinomycetes, the priority species competing bacteria do not become one type but cooperate with each other to express their effects.

The feature of this technology is that the spore of Natto and Actinomycetes cooperate with each other, and it has been confirmed that they are active even at 60 ° C. or less and 0 ° C. or less, which is difficult for bacteria to propagate normally. In addition, an aqueous solution having a salinity of 40000 mg / l, which has a higher salinity than seawater, is also decomposed and reduced.
The reduction / removal of heavy metals means that the concentration of heavy metals including sodium decreases in soil or in aqueous solution.

The greatest feature of the present invention is that natto and actinomycetes are selected and used as a material for reducing heavy metals.
Thereby, the activity of actinomycetes, which are aerobic bacteria, can be maintained by increasing the temperature to 30 ° C. or more for decomposing and reducing heavy metals and waste liquid.

Hereinafter, the present invention will be described based on the embodiments.
In the heavy metal treatment material of the present invention, natto bacteria and actinomycetes are supported on wood chips, soil, straw, pearwood, incineration ash (coal ash), etc., and these natto and actinomycetes are heavy metals and waste liquid. Is decreasing. Examples of actinomycetes include Streptomycene. The heavy metal treatment material can be supported by mixing natto and actinomycetes, or can be used by spraying a liquid material containing these. Heavy metals include at least lead, cadmium, copper, chromium, arsenic, boron, zinc, nickel, sodium, and the like.
Hereinafter, an example will be described.

Preparation of heavy metal treatment material As a heavy metal treatment material, add 10 ³ to 10 ¹² natto bacteria / gram to Streptomyces and streptomycene bacteria to 10 ³ to 10 ⁷ bacteria / g. A carrier made by heating and mixing in a fermenter having a humidity of 50 to 90% and a temperature of 30 to 70 ° C. for 6 hours was used.
A: Momiji + actinomycetes B: Momiji + actinomycetes + Natto bacteria C: Momiji + Escherichia coli Boron and cadmium were used as examples. Screening to obtain strains resistant to cadmium was performed.
For screening, NA culture medium PDA medium containing cadmium (1000, 1500, 3000, 5000, ppm), plating factory effluent and 100 μl of sludge water are dropped into each, and the bacteria are grown in a thermostat at 30 ° C. The culture was stationary until it was confirmed.
Thereafter, an experiment was conducted using a 50 ppm cadmium-containing medium to determine whether cadmium removal by bacteria was performed using a cadmium-resistant strain that had been confirmed to grow. As the strain, “actinomycetes / natto bacteria + actinomycetes / Escherichia coli” were also used.
As experimental conditions, mold is a medium of “bactopeptone 5 g, glucose 2 g, distilled water 1 l”, bacteria is NB medium, adjusted to contain a cadmium ion concentration of 50 ppm, and shaken at 35 ° C. for 5 days at 70 rpm. Cultured.
The measurement was performed by diluting 10 times with ICP / AFS every other day.

In sample A, boron was reduced by about 20%, but it was confirmed that about 50% of cadmium was removed.
In Sample B, it was confirmed that about 30% of boron and about 70% of cadmium were removed.
In Sample C, it was confirmed that about 20% of boron and about 40% of cadmium were removed.
Table 1. According to the report, boron was reduced by about 30% and the effect was not clear. In particular, when actinomycetes were used alone, the removal rate of boron was about 20%.
In Sample B using natto and actinomycetes, about 70% of cadmium was removed, which is promising as a heavy metal treatment material.

The samples A, B, and C used in Example 1 were subjected to an experiment using kimchi waste liquid containing a large amount of heavy metals.
A biobed in which 900 cc (15 × 15 × 4) is filled in a specimen of 5 cm thickness, 15 × 15 × 5 = 1,125 cc container.
Kimchi waste liquid is added to the 100 cc biobed daily.

In sample A, it was confirmed that 17% of chromium and 23% of nickel were removed.
In sample B, it was confirmed that chromium was removed by 35% and 57% or more was removed in the other 6 items.
In Sample C, it was confirmed that chromium, cadmium, and nickel were not removed.
In sample B using natto and actinomycetes, it is promising as a heavy metal treatment agent that 50% or more of 6 items have been removed. In addition, the fact that 6000 cc of kimchi waste liquid has been extinguished in 60 days is promising as a food waste liquid treatment agent.

Soil improvers that treat heavy metals in soil are 30-60 animal droppings, 10-30 sawdust, 20-40 rice husks, 20-80 parts by weight incinerated ash (such as clinker), and a predetermined amount of Bacillus natto and radiation. The predetermined amount of natto bacteria is 1,000,000 to 1,000,000,000 per gram of the total mixture, and then the mixture has a relative humidity of 30 to 80%. A food waste liquid treatment agent is obtained by performing a mixed superheat treatment at a temperature of 60 to 65 ° C. in a fermenting apparatus and fermenting the mixture by heat for 3 hours to 12 hours.

First, 10 kg of prepared sawdust (5 to 20 mm), 40 kg of rice husk (5 to 20 mm), 20 kg of incineration ash, and about 2 billion natto bacteria and actinomycetes in the total mixture, about 3 to 6 The mixture was thoroughly stirred until it was warmed and ventilated for a period of time and even.

The fermented product taken out from the fermenter after the mixed heat treatment is finished is the heavy metal treatment material of the present invention.

About 10 to 100 g per square meter is sprayed in a treatment area where soil improvement is necessary with a heavy metal treatment material. After spraying uniformly, mixing and stirring is performed to a depth of 20 cm from the ground surface with a cultivator or tractor.

The present invention does not use a special power source, and does not adversely affect the natural environment.It treats food waste and directly sprays it into soil contaminated with heavy metals, and mixes and agitates it. It can be widely used as a technique capable of reducing heavy metals in the inside.

Claims (5)

The present invention is characterized in that a carrier on which natto and actinomycetes are adsorbed and cultured is provided for removing trace heavy metals in soil and waste liquid. Microbial treatment agent, heavy metal treatment agent and soil conditioner. The heavy metal treatment material according to claim 1, wherein the heavy metal contains at least lead, cadmium, copper, chromium, arsenic, boron, zinc, nickel, and sodium. A microbial treatment agent that can reduce and eliminate food waste (sake lees, shochu, starch, pickles of pickles, etc.) and food residues simultaneously with the removal and reduction of heavy metals in the soil. A method for treating heavy metals, comprising using Bacillus natto and actinomycetes in order to reduce existing heavy metals in soil. Heavy metals in aqueous solutions include waste liquids such as kimchi and pickles, waste liquids such as automobiles, electrical equipment, semiconductors, and control rods of raw hydroelectric power plants, and heavy metals used as cleaning agents. A heavy metal treatment material characterized in that