JPS62237913A - Treating method and treating agent for polluted water - Google Patents

Abstract

PURPOSE:To enhance strength of flock of pollutant treating agent, increase its contact area, enhance dehydrating properties, and raise up strength of dehydrate by combining pollutant treating agent and fiber and treating polluted water. CONSTITUTION:A pollutant agglomeration treating agent reacts with water in a quick agitating tank 1 to turn into aluminum hydroxide, and when said aluminum hydroxide turns into flock in a slow agitating tank 2, fiber is contained in to reinforce said flock and enlarge the contact area of pollutant. Said fiber and flock are sent to a settling tank 3 to be treated, to which pollutant adheres and grows up in the settling process to turn into settled sludge. When said settled sludge is press dehydrated, fiber forms up a net to easily attain pressing pressure and accelerate dehydration.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for treating polluted water and a treatment agent therefor, and for example, to an efficient method for treating water supply and a treatment agent therefor.

Conventional technology Water supply water is drawn from dams, rivers, lakes, etc.

Since fine particles such as colloid particles, clay, and silt are suspended in this water, these must be removed and sterilized to make the water suitable for drinking. In order to remove these suspended solids, conventionally, as shown in Figure 3, raw water is introduced into a rapid stirring tank 1, where inorganic flocculants such as sulfuric acid and PAC are mixed and rapidly stirred. , these flocculants react with water to form aluminum hydroxide. When the water to be treated containing such aluminum hydroxide is then transferred to the slow stirring tank 2 and slowly stirred, the aluminum hydroxide forms flocs, with which the contaminant particles of the water to be treated come into contact. When the water to be treated is transferred to the settling tank 3 in this state, pollutant particles adhere to the flocs, which gradually increase in size during the sedimentation process and become precipitated sludge.On the other hand, the water to be treated from which the pollutant particles have been removed becomes a supernatant. It is extracted as a liquid. This supernatant liquid is sent to the next sterilization step, while the settled sludge is sequentially deposited on the bottom of the settling tank, and when a certain amount of sludge has accumulated, it is discharged outside the settling tank. Dumping this sludge as it is causes pollution, so its dumping is regulated. Therefore, it is concentrated in the concentration tank 4, water is removed to some extent, and then dehydrated in the filter press dehydrator 5. In this way a sludge cake is made.

Water treatment for waterworks is carried out in this way, but the important points are how well the pollutant particles in the water to be treated can be coagulated and settled to increase the treatment efficiency, and how the settled sludge can be treated. The key is to do it efficiently and how to deal with the results.

However, in the conventional method described above, the inorganic flocculant reacts with water to form flocs and then adsorbs pollutant particles, so there is a problem that this process takes time, and the inorganic flocculant reacts chemically when the water temperature is low. There was a problem in that a large amount of aluminum hydroxide had to be injected because it was difficult to form flocs.Furthermore, aluminum hydroxide flocs were easily broken during stirring, and if they were broken, the flocculating effect would be diminished. Furthermore, even if settled sludge is filter-pressed after being concentrated, the sludge is composed of microclimate particles such as silt, colloid, clay, and ridge grasses, and has fluidity, so pressing pressure does not work effectively and dewatering takes a long time. It takes time, and
A part that has become hard due to dehydration obstructs the flow of water from inside the part, and when attempting to force dehydration, more pressing pressure is required or more time is required for pressing. This significantly reduces work efficiency. Additionally, the mud cake made in this way has poor water permeability and returns to its original mud state when it rains, so a portion of it is burned in a boiler and the ashes are used as soil for bonsai. However, most of the waste has no other use other than being dumped, and there are restrictions on where this can be done.

The above was for waterworks, but when treating organic wastewater, it is also possible to improve the aeration effect by improving the contact between activated sludge and organic matter, and to improve the dewatering efficiency of activated sludge discharged from settling tanks. There were problems such as.

Problems to be Solved by the Invention As mentioned above, there is room for improvement in efficiently treating water containing pollutants such as waterworks and organic wastewater.
Furthermore, there is no suitable method for promoting the dehydration of materials that are difficult to dehydrate, such as these precipitates, and furthermore, there is no fundamental method for utilizing the cake after dehydration, and improvements have been desired.

Means for Solving the Problems In order to solve the above problems, the present invention provides a method for treating polluted water, which is characterized in that polluted water is treated by using at least a pollutant treatment agent in combination with fibers. It is something to do.

The present invention also provides a polluted water treatment agent characterized by comprising at least a pollutant treatment agent and fibers.

Next, the present invention will be explained in detail.

In the present invention, a pollutant treatment agent is an agent that is mixed with polluted water and used to aggregate pollutants or to serve as a nutrient source for a group of organisms (activated sludge) necessary for purifying organic polluted water. be.

Conventionally used flocculants can be used to flocculate pollutants, such as polyaluminum sulfate, aluminum sulfate (sulfuric acid band), aluminum chloride, polyaluminum chloride (PAC), iron hydrochloride, etc. Acid or alkali flocculants such as , iron sulfate, Kotsubarasu chloride, sodium aluminate, caustic soda, slaked lime, calcium carbonate, etc., polymer flocculants such as polyacrylamide, natural polymers, etc. are used alone or in combination. When these inorganic flocculants and organic flocculants are used together, the effect of flocculating pollutants can be enhanced. Moreover, urea, phosphoric acid, etc. are mentioned as a nutrient source.

Furthermore, in the present invention, the fibers may be either natural or synthetic; for example, cellulose fibers include wood pulp fibers, linen, cotton, etc., and synthetic fibers include polypropylene, nylon, vinylon, polyester, etc. Examples include fibers. Among these, cellulose fibers are advantageous in dehydrating precipitates because of their good dehydration properties, large surface area, and high strength.

As the cellulose fibers, used paper such as Shinkai paper or magazines may be soaked in water and stirred to make it mushy, or cellulose powder may be used. This cellulose powder is made by acid hydrolyzing selected pulp, for example.
After filtering and washing with water, the fibers are removed, dried, crushed, and sieved, or the fine fibers are separated into short fibers, dehydrated, dried, crushed, and sieved. For example, moisture content is 7% or less, ash content is 0.25% or less, bulk specific gravity (compact) axis/
CC) is 0.15 or less, 0.40 or more, 0.15 to 0
．． Several types between 40 and pH 6.0 to 8.0 or 5
．． 0 to 7,0, particle size (900% pass) (methos) is 4
2.50.100.200.250.300, 400
There are a variety of things that can be mentioned. The properties of these cellulose powders include being negatively charged in water, adsorbing metal ions and cationic substances, and absorbing acids, alkalis,
Examples include those that are stable against oxidizing agents and organic solvents, absorb water and swell, and also have oil absorbing properties. Specific examples include KC flock and pulp flock (trade name).

In the present invention, the above-mentioned flocculant, nutrient source and fiber may be separately introduced into the polluted water area, but a sewage treatment agent containing these may also be used.

The sewage treatment agent of the present invention has at least the above-mentioned flocculant, nutrient source, and fiber, and may be in powder or liquid form. When powdering, the fiber powder and a powder flocculant may be mixed, but it is preferable to mix the fiber powder with a liquid flocculant and let the flocculant penetrate into the fibers. The blending ratio of fibers and flocculant can be arbitrarily selected depending on the concentration of the polluted water to be treated, etc., but for example, a mixture of 7 to 8% PAC and 10 to 20 sulfuric acid hand liquid flocculant to 100 fibers may be used. It can be used as a powder made by impregnating fibers with a flocculant. However, it is also possible to use a mixture of fibers and flocculants in any ratio. Powdered sewage treatment agents are advantageous because unlike liquid ones, they do not require a pressure pump.

The mixing ratio of the nutrient source and fiber can also be considered in accordance with the above.

Working fibers do not react with water like flocculants in polluted water, but they not only act as a core and attach pollutants from the beginning, but also
When the flocculant reacts with water to form flocs, it reinforces the flocs, making them difficult to break and retaining the flocculation effect well.Furthermore, the contact area of pollutants increases due to the fibers, increasing the flocculation effect. . In addition, the precipitate is mixed with fibers, which when entangled with each other create a network structure, suppressing the fluidity of the precipitate and making it easier to apply press pressure, increasing its strength and being used as top soil. become able to. In particular, cellulose fibers absorb water, so when they are in hardened mud, they function as a water flow path.
It promotes press dewatering, and when used as top soil, its water absorption properties improve water depth and drainage.

Next, one embodiment of the present invention will be described based on FIG.

In the drawings, the same reference numerals as those on the map indicate the same components. Raw water is introduced into a rapid stirring tank 1, and a sewage treatment agent is mixed therein for treatment. These stirred materials are then sent to a slow stirring tank 2 for slow stirring treatment, and then transferred to a settling tank 3. Here, the pollutants are coagulated and sedimented, and a supernatant liquid is taken out, while the sedimented substances are sequentially deposited on the bottom of the settling tank 3 as settled sludge. This settled sludge may be sent directly to the press dehydrator 5, but it is stirred and mixed with the cellulose fiber mixture from the cellulose fiber water mixing tank 6 in the agitation tank 7, and this mixed liquid is mixed with the filter press dehydrator by the pump 8. 5 and may be dehydrated.

In the above, specific formulation examples of sewage treatment agents include:
7 of PAC or sulfuric acid band to 100 parts by weight of KC floc
An example is one in which 1 to 2 parts by weight of a ~8% solution is mixed, and 1 to 3% of polyacrylamide is further mixed with the flocculant solution to impregnate the fibers with the flocculant.

When the raw water is treated as described above, the pollutant flocculation treatment agent reacts with water in the rapid stirring tank 1 and becomes, for example, aluminum hydroxide, which becomes flocs in the slow stirring tank 2. This strengthens the flocs and increases the contact area for pollutants.

When such fibers and flocs are sent to the sedimentation tank 3 and treated, pollutants adhere to them and become larger during the settling process to become settled sludge. When this precipitated sludge is dewatered by pressing, the fibers can form a network structure, making it easier to apply pressing pressure and promoting dewatering. At this time, when cellulose fibers are mixed with the settled sludge and dehydrated, the fibers act as water channels due to their water absorption properties, further promoting dewatering. The cake made in this way has a network structure of fibers that strengthens the easily flowing mud, allowing it to maintain the consistency of regular field soil. Moreover, if this soil contains cellulose fibers, it will retain water well even when used as soil for fields etc. due to its water absorption properties, and will also have good drainage.

``Sec. 2'' describes the water treatment of two taps, but as shown in Figure 2, it can also be applied to the treatment of organic wastewater.

That is, organic wastewater is led to the aeration tank 1), where it is mixed with a sewage treatment agent consisting of eutrophic sources and fibers and aerated as in the case of FIG. The precipitated sludge is sent out by a pump 8 and dehydrated by a press dehydrator 9. In this way, the filamentous bacteria will be captured by the fibers and the sedimentation and consolidation of the sludge will not be affected (bulking prevention), and the treated water in the sedimentation tank will not deteriorate. At the same time, the strength of the fluorocarbon resin will be improved, and the sludge will The contact area is large,
It can be acclimatized in a short time and the dehydration properties of TQ mud can be improved.

The above can also be used by treating sewage or sludge from rivers, lakes, the sea, dams, ponds, etc. as described above.

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, wastewater can be treated by using a pollutant treatment agent and fibers together, using them separately, or using them simultaneously with a sewage treatment agent composed of at least these. This improves the strength of the floc of the pollutant treatment agent, increases its contact area, improves treatment effects such as coagulation or oxidation of pollutants, and improves the dewatering properties of sediment. The strength of the dehydrated product can be increased to enable its use as soil. This not only improves wastewater treatment efficiency and productivity, but also makes it possible to effectively utilize wastewater sediments, which have been troublesome in the past.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an apparatus used in a method according to one embodiment of the present invention, FIG. 2 is an explanatory diagram of an apparatus used in a method according to another embodiment, and FIG. 3 is an explanatory diagram of a conventional apparatus. In the figure, 1 is a rapid stirring tank, 2 is a slow stirring tank, 3 is a settling tank,
4 is a Na contraction tank, 5.9 is a press dehydrator, 6 is a cellulose fiber water mixing tank, 7 is a stirring tank, 8 is a pump, 1) is an aeration tank, and 12 is a settling tank. April 8, 1986

Claims (2)

[Claims] (1) A method for treating polluted water, which comprises treating polluted water by using at least a pollutant treatment agent and fiber in combination. (2) A polluted water treatment agent comprising at least a pollutant treatment agent and fibers.