JPH02284700A - Treating agent for purifying and separating sludge - Google Patents

Abstract

PURPOSE:To efficiently remove a foul odor by adding a treating agent consisting essentially of salts of di- or trivalent iron, a specified metal and an alkaline earth metal. CONSTITUTION:A treating agent consisting of 50-30wt.% salt of di or trivalent iron, 45-30wt.% salt of a trivalent metal and 30-3wt.% salt of an alkaline earth metal such as magnesium chloride or calcium chloride and further contg. 1.5-0.3wt.% P2O5 as necessary is added. With the agent, adsorption, caking and drying can be carried out in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is applicable to dams, lakes, rivers, seabed sediments and 7'1. Hydrophilicity of pollutants such as mud, pollutants, red tide, n-powder, etc., and pollutants of industrial wastewater, such as wastewater from fisheries, M-products, and agricultural food processing, or industrial wastewater, such as metal sludge or slurry. A purification and separation treatment agent for sludge that hydrophobizes colloidal particles, separates and dehydrates water molecules to form residual solids and separated water, and makes each of them available for effective use, and sludge using the purification and separation treatment agent. Concerning purification and separation methods of

[Conventional technology]

Sludge such as sedimentary bottom sludge from lakes, rivers, and the ocean floor, and industrial wastewater pollutants generally contain organic substances such as proteins, carbohydrates, and fatty acids, inorganic substances, and bacteria, and fine particles of 1 micron or angstrom units of organic or inorganic substances. It is composed of fine particles, which exist in colloidal form in water, and many of them are hydrophilic, making their removal and separation difficult.

Conventionally, methods for purifying and separating sludge, such as sludge deposited in lakes, rivers, and the seabed, or industrial wastewater pollutants, have been used to separate water and solidify the residue. , ■ Solar drying treatment, which takes a long period of time in a landfill, then consolidates and waits for natural dewatering until it meets the purpose of use, ■ Mechanical dewatering treatment, which solidifies the mud by forcibly dewatering it with a dewatering machine. How to get things done.

■There is a chemical dehydration treatment method in which the moisture content is lowered by coagulating sedimentation and concentration using a polymer flocculant, and then treatment is performed using lime, cement, or a solidifying agent. , a sludge treatment agent consisting of a divalent or trivalent iron salt, a trivalent metal salt, a monovalent gold scrap salt, and solvent water (
JP-A-62-277199), ■At2. A liquid inorganic flocculant (Japanese Patent Application Laid-Open No. 14911/1983) consisting of an aqueous solution of basic aluminum iron sulfate containing specific amounts of three components, Fed and SO, is known, and attempts have been made to use these treatment agents. There is.

[Problem to be solved by the invention]

The conventional bending technology has the following drawbacks, for example. ■
In the solar drying process, water molecules are evaporated from the bottom mud over a large area and over a long period of time, but during this period, there is a foul odor peculiar to the bottom mud, and when it is exposed to rain or snow, it liquefies again and produces a bad odor. Release.

Difficult to use as landfill soil, etc. In the case of (2), the mechanical dewatering treatment method only reduces the water content by squeezing water out of the bottom mud, even if a large amount of money is invested, and does not improve odor, soil quality, or water quality.

Furthermore, since the sludge is not completely solidified, it is difficult to use it as land for landfill or embankment. In addition, lime and cement are used in the chemical dehydration treatment method (■), but these only solidify the bottom mud and make it easier to dispose of, and cannot improve the soil quality. Along with this, alkaline content is washed away from the treatment area due to the influence of rainwater and spring water over a long period of time, causing a problem of deterioration of water quality in downstream rivers.In the case of the treatment agents listed in ■ and ■ above, In order to sufficiently separate water, not only is pretreatment such as treatment with a polymer flocculant required first, but water separation is still poor and takes a long time, and bacteria.

No effect was observed in detoxifying heavy metals or eliminating odors.
The separated water also has problems in that its usage range is limited, so the bottom mud can be made hydrophobic quickly.1 Separated water,
It also makes it possible to sterilize bacteria and detoxify heavy metals contained in the separated bottom mud, and the soil particles can be regenerated into the soil particles before the bottom mud, and the range of use is not limited, and can be used as land fill, embankment soil, or fertilizer. It is hoped that a method and treatment agent will be developed that will make it possible to hydrophobize pollutants of industrial wastewater, such as industrial metal sludge, or pollutants of wastewater from agricultural, livestock, and seafood processing processes. Done.

It is expected that a method and a treatment agent will be developed that will make it possible to sterilize bacteria and detoxify heavy metals contained in separated water and solid matter.

[Means to solve the problem]

As a result of intensive research to solve the above-mentioned problems, the inventor of the present invention found that
An aqueous solution containing metal salts mainly composed of alkaline earth metal salts in addition to divalent or trivalent iron salts and trivalent metal salts can be used as a purification and separation treatment agent for sludge, alleviating the above-mentioned problems at once. We have discovered that this problem can be solved, and have arrived at the present invention.

That is, the present invention provides a purification and separation treatment agent for sludge, which has divalent or trivalent iron salts, trivalent metal salts, and alkaline earth metal salts as main components, and which is prepared by dissolving the inorganic salts in solvent water; A sludge purification and separation treatment agent is prepared by adding diphosphorus pentoxide to this product, and the above-mentioned sludge purification and separation treatment agent is added to the sludge, and then a polymer flocculant is added to the sludge. The present invention relates to a method for purifying and separating sludge by hydrophobizing and separating sludge, that is, a method for separating and recovering reusable high-quality water and residue from sludge such as bottom sludge and industrial wastewater pollutants.

In the sludge purification and separation treatment agent of the present invention (hereinafter referred to as purification and separation treatment agent bottom sludge improver), divalent and trivalent iron salts include ferrous sulfate, ferric sulfate, ferric chloride, etc. Examples of trivalent metal salts include aluminum sulfate [A12(
S04)3), aluminum potassium sulfate (AIK(
So, ), ), etc. These metal salts are commonly used as flocculants for sludge water treatment.

In the present invention, an alkaline earth metal salt is further added to the divalent and trivalent iron salts and trivalent metal salts, and the alkaline earth metal salt is magnesium chloride (MgClz
・6HJ), calcium chloride (CaC12・21(, O
) etc. These alkaline earth metal salts, such as Mg
Cl2.6H20 is used as a coagulant for tofu, a cooling agent, and a raw material for cement.
□ is a desiccant, a calcium binder for skeletal diseases as a medicine,
It is widely used in the treatment of allergic diseases, but
There are no examples of these alkaline earth metal salts being used as treatment agents for sludge such as bottom sludge or pollutants of industrial wastewater, and the purification and separation treatment agent of the present invention containing these alkaline earth metal salts can remove water and solids from sludge. The synergistic effect of alkali metal salts and flocculants such as aluminum sulfate, ferric chloride, and ferric sulfate allows sludge to coagulate easily, making adsorption, solidification, and drying possible in a short time. It has excellent effects such as being able to perform

In the present invention, diphosphorus pentoxide (P
, Os) can be used as a purification and separation treatment agent. P2O is used for dehydration, gas drying, condensing agent and surfactant in organic chemistry, and digestion for medical purposes.

Although it is known as a refreshing agent, the present inventor has discovered for the first time that it acts as a detoxifier and disinfectant for heavy metals and bacteria in sludge, and also as a neutralizing agent that neutralizes alkalinity to acidity. This is what I found.

The composition ratio of the components of the purification and separation treatment agent of the present invention is appropriately selected depending on the source of the sludge to be treated, that is, the components constituting the sludge, particle size composition ratio, water content, PH, temperature, etc. 50-30% by weight of divalent or trivalent iron salts, 45-30% by weight of trivalent metal salts, 30-3% by weight of alkaline earth metal salts, and ~0.3% by weight of p, o, i, s. can be processed effectively.

In the present invention, the amount of solvent water, which is the main component, is preferably at least 4 times the total weight, but it is also possible to use an amount less than this, but in that case, the respective chemical components may react with each other, and the effects and effects may be reduced. May decrease.

The amount of purification and separation treatment agent used is not particularly limited, but it is 1 to 30ρ for sludge (moisture content 10%) i, ooop.
, preferably 3 to 6Q.

In the treatment of sludge, after treatment with the purification and separation treatment agent of the present invention, the hydrogen ion concentration in the water increases due to the positively charged metal salts of the purification and separation treatment agent, the pH decreases, and the coagulation and coagulation reaction slows down. Therefore, the neutralizing agent calcium hydroxide (
Treated with Ca(○H)2), sodium hydroxide (NaOH), magnesium oxide (MgO), etc. to lower the hydrogen ion concentration.

The pH is raised to allow the coagulation and coagulation reaction to occur smoothly. These neutralizing agents are selected depending on the source of the sludge, and the pn is adjusted to about 6 to 8.6. Calcium hydroxide is widely used as a neutralizing agent, and sodium hydroxide is strongly alkaline and is compatible with sediment treatment in seawater. Moreover, MgO acts as a neutralizing agent and as an antidote since it forms an insoluble salt with arsenous acid.

Furthermore, in treating sludge, a polymer flocculant can be used in combination. Thereby, the coagulation and coagulation reaction between the sludge particles can be further promoted. The sludge quickly forms large flocs and settles due to the synergistic effect with the purification and separation treatment agent. Polymer flocculants include various types of anionic, nonionic, and cationic polymer flocculants.
0K107 (registered trademark) (Kyoritsu Organic Industry Co., Ltd.)
], Nononin uses polyacrylamide [Himoloku 55200 (registered trademark) (Kyoritsu Organic Industry Co., Ltd.)
].

For cations, polyacrylamide type [Himoloku M
P], 73, Q 101, Q+, 05 (registered trademark)
(Kyoritsu Organic Industry Co., Ltd.)] etc. are used.

The treatment of sludge using the purification and separation treatment agent of the present invention is as follows:
For example, this is done as follows. A certain amount of purification and separation treatment agent is added to sludge and mixed. As a result, the separation of water and solids progresses, and the sludge easily coagulates and coagulates. Furthermore, a neutralizing agent and then a polymer flocculant are added to this, the treated material is separated into flocs and water in a sludge separation tank, and the separated solids are dehydrated in a dehydrator to form a solid residue (separation top, etc.) get.

The purification and separation treatment agent of the present invention can be used to treat organic, inorganic, or neutral sediment in fresh water, to treat sediment in freshwater containing metal layer bacteria, to treat sediment in sea water containing heavy metal bacteria, etc. It is effective in treating sludge such as various types of bottom sludge and various industrial wastewater turbidities, such as various industrial wastewater pollutants, such as various metal sludges, agricultural, water, and livestock wastewater pollutants. be.

[Effect]

The main component of the sludge purification and separation treatment agent of the present invention is a positively charged inorganic metal salt, which binds to and neutralizes the negatively charged fine particles constituting the sludge, thereby reducing the solid matter of the sludge and the biological waste. Water molecules that have been attached and restrained around the particles are separated from the particles, and further water molecules are pushed out due to the agglomeration and coagulation reaction of the solid particles, forming flocs that are aggregated into large particles. it is conceivable that. In particular, since the purification and separation treatment agent of the present invention contains an alkaline earth metal salt, conventional sludge treatment agents of this type required first treatment with a polymer flocculant as an auxiliary agent.

The present invention does not require such pretreatment,
Hydrophilic colloid particles can be effectively converted into hydrophobic colloid particles, which can be aggregated, adsorbed and solidified to form a solid mass, and the particles can be made into large agglomerates. It also has a deodorizing effect, eliminating bad odors, sterilizing bacteria and heavy metals, and detoxifying. Also, the separated water has no contaminants and is of high quality.

The soil from the separated bottom sludge has low water retention and high permeability, and can be used as soil for reclamation and embankment, and the solids obtained from industrial wastewater, such as metal sludge, can be used as additives for the ceramic industry. Each can be used in a variety of ways, including as a.

〔Example〕

The present invention will be explained below with reference to examples, but it goes without saying that the present invention is not limited to these examples.

Table 1 shows the amount (blending ratio) of the components in the solvent water IQ of the purification and separation treatment agent of the present invention used specifically and the order of addition of the treatment agent in treating sludge. In Table 1, Example 1 is for organic, inorganic, and neutral freshwater sediment sediments, Example 2 is for freshwater sediment sediments containing heavy metal bacteria,
Example 3 is for treatment of sedimentary bottom sludge in seawater containing heavy metal bacteria, Example 4 is for wastewater pollution during canned fish food processing, and Example 5 is for wastewater lη turbidity during food processing of Alaska pollack surimi. Example 6 shows the treatment of cleaning wastewater slurry during the manufacture of electronic parts, and the ratio is that of the comparative example (Japanese Patent Application Laid-Open No. 62-277199).
The same bottom mud as in Example] was treated.

The processing method is as follows.

Sludge such as bottom sludge is transported through a pipe, and 7 purification and separation treatment agents are added at a ratio of 3 to 6 Q per 1,0 OOQ of the sludge (gold mud ratio: 10%). While transporting the mixture, a neutralizing agent and a polymer flocculant are added to treat the sludge, which is then introduced into a sludge separation tank to separate water and solid residues (soil, etc.) that coagulate and precipitate. , the residue was treated with a dehydrator (7° dehydration to obtain a dry separated solid. Also, for comparative examples, first, a polymer flocculant, a sludge-forming hydrophobic agent,
It was treated with a neutralizing agent and a polymer flocculant in this order.

The results obtained are shown in Table 2. In the table, the concentrations of the neutralizing agent and polymer flocculant are 110 g/Q and 2 g/Q, respectively.
It was Q.

Table 2 Table 2 [Effects of the Invention] The sludge purification and separation treatment agent of the present invention can be used to treat bottom sludge from dams, lakes, rivers, seabeds, etc., as well as various wastewaters from industries, agricultural water, livestock products, and food processing. Sludge materials such as pollutants can be dehydrated in an extremely short period of time, and the resulting separated solids do not re-sludge (liquefy). Can be played.

In addition, the purification and separation treatment agent of the present invention can deodorize or deodorize the bad odor peculiar to sludge, sterilize the bacteria contained therein, and detoxify heavy metals. It can be reused, for example, when separated from bottom mud, it can be used as a soil improvement material for landfills, embankments, and agricultural land, and in the case of solids from metal sludge or slurry, it can be used as an additive for the ceramic industry. , the separated water is returned to lakes, rivers, oceans, etc.
It can be said to be an epoch-making invention as it can be used as a water resource and contributes to the purification and utilization of sludge at an economical cost.

Claims (7)

[Claims] (1) A purification and separation treatment agent for sludge, which contains divalent or trivalent iron salts, trivalent metal salts, and alkaline earth metal salts as main components, and is prepared by dissolving the inorganic salts in solvent water. (2) A purification and separation treatment agent for sludge, which is obtained by adding diphosphorus pentoxide to the agent for purification and separation of sludge according to claim 1. (3) The agent for purifying and separating sludge according to claim 1 or 2, wherein the sludge is bottom sludge. (4) The agent for purifying and separating sludge according to claim 1 or 2, wherein the sludge is industrial wastewater pollutant. (5) The agent for purifying and separating sludge according to claim 1 or 2, wherein the alkaline earth metal salt is magnesium chloride or calcium chloride. (6) A method for purifying and separating sludge, which comprises adding the agent for purifying and separating sludge according to claim 1 or 2 to sludge, and hydrophobizing and separating the sludge. (7) The agent for purification and separation of sludge according to claim 1 or 2 is added to sludge, and then a neutralizing agent comprising calcium hydroxide, sodium hydroxide or magnesium oxide and a mixture thereof, and a polymer A method for purifying and separating sludge, which comprises adding a flocculant to hydrophobize and separate sludge.