KR100305392B1 - A red,blue,green tide restrainer or that's process using purification plant sludge and convert slag - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control agent for controlling red tide, green algae, and blue algae generated in seawater or freshwater on the coast or inland using sludge generated in a water purification plant and converter slag generated during a steelmaking process. It solved the problem of the temporary effect of the ocher adsorption method and the excessive cost generation of other methods, and the control to make red tide control by using the waste water purification plant sludge and converter slag containing components that sterilize red tide organisms. By manufacturing the agent, the waste resources can be recycled as high value-added resources, thus reducing the cost of the control and supplying materials for producing a stable control agent.

Description

A red, blue, green tide restrainer or that's process using purification plant sludge and convert slag}

The present invention relates to red tide and green algae, green algae control agent and a method for manufacturing the same, which occur in the sea and reservoirs due to eutrophication by phosphorus (P), in particular red tide and green algae using converter slag generated in sludge and steel mills in waterworks. The present invention relates to a freshening agent and a manufacturing method thereof.

Known methods of controlling and removing red and green algae, and blue algae (hereinafter abbreviated as red tide) organisms include chemical spraying methods that destroy the cells of red tide organisms, methods of filtration or centrifugation of red tide organisms to recover them from the sea surface, and There is a method of adsorbing, coagulating and precipitation red tide organisms using loess or polymer coagulant. Among them, the relatively high effect is the method using the property of spraying ocher (Kaolinite, Montmorillonite) in seawater by sedimentation of red algae and sediment of red tide organisms by elution of aluminum ions in ocher to destroy the cells of red tide. It is being studied and used in Korea.

However, the ocher spray method only causes coagulation which is commonly found in finely divided particles, and the theory that red tide is destroyed by elution of Al ³⁺ ions has been controversial due to its authenticity. In addition, there is a case that the destruction of insects and shellfish in the mud flats caused by the ocher spray is required a lot of verification. Hazardous crude algae control ingredients are composed of Al ₂ O ₃ and Al ₃₊ . Al ₂ O ₃ contains about 8-12% of yellow soil, which has the adsorption effect of toxic plankton causing red algae or fresh blue. ³⁺ is known to kill toxic plankton, which is generally found to contain 4-12% of loess. However, spraying ocher is not only a long-term solution but only a temporary effect after spraying, and it is a uniform ingredient containing a large amount of Al ₂ O ₃ , Al ³⁺ and Ca ³⁺ , which can control or suppress red tide. It is also difficult to find a loess having a single supply is not simple, so it will be difficult as a raw material for the manufacture of red tide inhibitors.

On the other hand, the inventors of the present invention have found that the water treatment plant sludge and converter slag from the tap water purification process are very suitable as the material of the red tide control agent in the search for a stable feed material for preparing the red tide control agent.

That is, the water purification plant sludge has a finer grain size and uniformity than that of the soil, and the Al salt and PAC (Poly Aluminum Chloride) injected in the water purification process remaining in the sludge and fine powder sludge contained in the water purification sludge are suitable for the control of red tide organisms. As a large amount of sludge occurs in the water treatment plant, a stable supply can be guaranteed. Moreover, since all of them are currently buried in the soil and disposed of, it is possible to recycle the purified water sludge, which caused the soil physicochemical properties by refining by the destruction of the structure, into a material having high value.

In addition, the converter slag generated during the steelmaking process has a high adsorption capacity, and contains a large amount of free calcium oxide having a coagulation effect of FeO component and sterilization effect of red algae, so that it is mixed with a water purification plant sludge to prepare a red tide control agent. In addition, waste can be recycled as a material with high value, and it is possible to manufacture a red tide control agent that can prevent environmental pollution.

Therefore, an object of the present invention is to prepare a red tide control agent to increase the efficacy by using only the purified water sludge alone, or by mixing the converter slag in the purified water sludge.

Hereinafter, the present invention will be described in detail.

First, the chemical composition of the water purification plant sludge used as the red tide control agent in the present invention is composed of components of raw water itself, a flocculant and a dehydrating agent, and mainly divided into silica, alumina powder, ignition content, etc. Silica (SiO ₂ ) 35-50%, alumina (Al ₂ O ₃ ) 20-30%, and the ignition content 15-30%. The ignition content is composed of organic matter, carbon, chemically bonded water, etc., and it shows a sharp loss between 200 and 400 ° C, and almost all the amount is reduced by more than 90% at 500 ° C and 600 to 800 ° C. This loss change also affects the loss of micro-ocher and Al (OH) ₃ , which is affected by the dehydration of Al ₂ (OH) ₃ · 3H ₂ O due to the micro-ocher and flocculant in raw water.

The ignition loss shows a change according to the measured temperature, and especially, it shows a rapid change in the loss between 200 ~ 400 ℃. The specific gravity of the water treatment plant sludge is 2.0 ~ 2.4, and the particle size analysis of the water purification plant sludge is 0.5 ~ 50㎛. It is composed of relatively fine grains, and the passing rate of # 200 sieve is over 95%.

As such, the water purification plant sludge may function as a control agent of red tide organisms by the sterilizing power of Al ³⁺ contained in the sludge.

On the other hand, the chemical composition of converter slag produced in steel production in steel mills is 40 to 46% by weight of calcium oxide (Ca0), 2 to 8% of magnesium oxide (Mg0), 10 to 15% of silicon oxide (SiO ₂ ), and oxidation It consists of 1-2% of aluminum (Al ₂ O ₃ ), 18-30% of iron oxide (FeO), and 5-7% of manganese oxide (MnO), and the converter slag is generally more oxidative than required. Calcium (CaO) is required. Therefore, in the case of LD converter slag, when the total CaO content is 4 to 40%, free CaO is often 1 to 4%, and in some cases, it may exceed 10%.

Therefore, the aggregation effect of the FeO component in the converter slag and free calcium oxide have a sterilizing effect of the red tide organisms, so it can have the function of the red tide control agent.

Table 1 shows the results of chemical analysis of ocher, tap water sludge and converter slag. When comparing the components of ocher, tap water sludge and converter slag, red tide and green algae are removed or reduced in tap water sludge and converter slag as well as ocher. It can be seen that there are many components (aluminum oxide, calcium oxide) which are useful for making.

Table 1

Therefore, in the present invention, using only the water sludge as a red tide control agent by using the red tide sterilization power of Al ³⁺ in the water sludge, or a converter slag containing FeO component and free calcium oxide in the water sludge to maximize the red tide disinfection effect of the water sludge. The mixture is used as a red tide control agent, but by mixing and spraying water sludge containing a large amount of Al ³⁺ and converter slag containing a large amount of CaO and FeO in a certain ratio, the fluid plankton, which is a causative agent of red tide, green algae and blue tide, is sprayed. It can be easily removed, and in particular, by using the eluting properties of the converter slag to continuously dissolve in the sea water, the effect can be long lasting.

The red tide control effect was examined by adjusting the mixing ratio of the purified water sludge and converter slag.

<Example 1>

After drying the water sludge, pulverize fine powder, mix 1: 1 with converter slag powder, take water from red tide occurrence area containing 2,600 coclodinium in 1ml, and sprinkle water in powder form for 1 hour, 3 hours, 5 hours. The number of later red tide organisms was measured.

<Example 2>

Powdered converter slag powder, mixed 1: 1 with tap water sludge, pelletized it (5 ~ 10mm), and then sprinkled and sprayed water in red tide occurrence area containing 2600 coclodinium in 1ml, and then 1 hour, The number of red tide organisms after 3 hours and 5 hours was measured.

<Example 3>

After drying and crushing tap water sludge, the number of red tide organisms was measured for 1 hour, 3 hours, and 5 hours after sprinkling and spraying water from the red tide occurrence area containing 2600 coclodinium in 1 ml.

<Example 4>

The number of red tide organisms was measured 1 hour, 3 hours and 5 hours after sprinkling water from the red tide occurrence area containing 2600 coclodinium in 1ml.

The results of Examples 1 to 4 are shown in Table 2.

[Table 2]

As a result of looking at the results of the embodiments in Table 2, the number of red tide organisms in any case is lower than in the case of the conventional yellow soil spraying as a comparative example, the tap water sludge and converter slag powder as in the case of Examples 1 and 2 The effect of the mixed form and the form of pelletized powder was found to be the best. Therefore, it is preferable to use converter slag mixed rather than using only tap water sludge alone.

<Example 5>

In order to examine the effect of PO ₄ ^3- , which causes red tide, add 100 g of powder and 10 cc of 0.1 N H ₃ PO ₄ solution, respectively, from three samples such as tap water sludge, converter slag, and yellow soil. After stirring for 30 minutes, the concentration decrease of PO ₄ ^3- ions was measured.

The results of the experiment are shown in Table 3.

Table 3

In addition, according to Example 5, it was confirmed that the water supply sludge and the converter slag influence the decrease in the concentration of phosphoric acid (PO ₄ ^3- ), which is the main cause of the red tide.

Therefore, it was confirmed that the water spray sludge alone or the converter slag mixed spray were effective only against the inhibition of phosphoric acid elution, and did not adversely affect farmed fish and endogenous organisms.

<Example 6>

We investigated the possibility of deagglomeration of laboratory algae using tap water sludge for algae that occurred temporarily and rapidly in the appeal. The algae were concentrated using plankton nets in the surface waters of the lakes of the lake, diluted with 20 L of lake water, filtered through a 150 μm sieve, and evenly dispersed. As an experimental flocculant, tap water sludge treated with liquid aluminum sulfate Al ₂ O ₃ 8% and polyaluminum chloride (PAC: Poly Aluminum Chloride, Al ₂ O ₃ 10%) were used. COD, TN, TP, PO ₄ -P and Chl-a analysis of the samples were conducted according to environmental pollution process test method. The organic matter content of ocher was measured after incubation for 30 minutes at 550 ℃, and the heavy metal content was AA and ICP. It was measured by. Phosphatase activity was modified by Hoppe's method, using Methylumbelliferyl-phosphate as substrate and incubated at 25 ° C for 3 hours and analyzed by fluorescence spectrometer. Microcystis aeruginosa is the dominant species (99%) and Chl-a was added to 249µg / l, 0.05g / l, 0.1g / l, 1g / l, and then aerated for 5 minutes and precipitated for 1 hour. As the water sludge concentration increased to 2%, 22%, 36%, 74%, and 89%, the removal rate of algae also increased proportionally due to the yellow soil adhering to the Microcystis aeruginosa floc. Table 4 shows the effects of mixing the water supply sludge with converter slag. That is, the removal rate of Chl-a increased or the removal rate of PO ₄ -P increased. Therefore, tap water sludge and converter slag may be aggregated with algae on particulate matter to increase precipitation or affect precipitation of dissolved PO ₄ -P. The results are shown in Table 4.

Table 4

Hereinafter, the manufacturing method of the present invention will be described.

The present invention is a drying furnace for maintaining a temperature of 70 ~ 90 ℃ water sludge consisting of 35-50% silica (SiO ₂ ), 20-30% alumina (Al ₂ O ₃ ), 15-30% of the ignition content. Drying step, grinding the dried tap water sludge into fine powder by vibrating mill, chemical composition of calcium oxide (CaO) 40-46%, magnesium oxide (MgO) 2-8%, silicon oxide ( A converter slag consisting of 10 to 15% of SiO ₂ , 1 to 2% of aluminum oxide (Al ₂ O ₃ ), 18 to 30% of iron oxide (FeO), and 5 to 7% of manganese oxide (MnO) is used with a ball mill or a vibration mill. It comprises a step of grinding into a particle size of 1㎛ ~ 10cm, a step of removing the iron by passing the pulverized converter slag through a magnetic separator, and a step of mixing the crushed tap water sludge and converter slag.

At this time, the water supply sludge and converter slag in the powder state are preferably sprayed by mixing in a ratio of 2: 1 to 1: 2, but only the water supply sludge powder may be sprayed in the area where the red tide is in progress, and the powder state Water sludge and converter slag can also be pelletized and spread.

The present invention enables the control of red tide using tap water sludge and converter slag that has been disposed of in the soil, or almost discarded, and thus the economic benefits and control costs obtained by adding value to waste as well as protecting the soil and marine resources. It is possible to reduce the efficiency of the stable supply of materials for the manufacture of the control agent.

Claims (4)

For the red tide, green algae, and blue sea salt control agents, the water treatment plant sludge powder consisting of 35 to 50% of silica (SiO ₂ ), 20 to 30% of alumina (Al ₂ O ₃ ), and 15 to 30% of ignition is applied to red, green and Red tide, green algae, and green algae control using water purification plant sludge and converter slag, characterized in that it is used as a clearing agent. The water treatment plant sludge has a chemical composition of 40 to 46% of calcium oxide (CaO), 2 to 8% of magnesium oxide (MgO), 10 to 15% of silicon oxide (SiO ₂ ), and aluminum oxide (Al ₂ O _3). ) 1 to 2%, 18 to 30% of iron oxide (FeO), and 5 to 7% of manganese oxide (MnO) are mixed in a ratio of 2: 1 to 1: 2. Red tide and green algae, green tea control agents. Process of drying water sludge consisting of 35-50% of silica (SiO ₂ ), 20-30% of alumina (Al ₂ O ₃ ) and 15-30% of ignition content in a drying furnace maintaining the temperature of 70-90 ° C And, grinding the dried tap water sludge into a fine powder using a vibration mill, and the chemical composition is 40 to 46% of calcium oxide (Ca0), 2 to 8% of magnesium oxide (MgO), and silicon oxide (SiO ₂ ). A converter slag consisting of 10 to 15%, 1 to 2% of aluminum oxide (Al ₂ O ₃ ), 18 to 30% of iron oxide (FeO), and 5 to 7% of manganese oxide (MnO) is used to obtain a slag of 1 μm to Water purification sludge produced by the process of grinding to a particle size of less than 10cm, the process of removing the iron by passing the pulverized converter slag through a magnetic separator, and the process of mixing the crushed tap water sludge and converter slag Manufacturing method of red tide, green algae, and green algae control by using The method of claim 3, further comprising pelletizing powdered water sludge and converter slag mixed in the process.