KR100225182B1 - Artificial culture soil composition and method of preparation thereof - Google Patents

Abstract

The present invention comprises a viscosity increasing agent selected from paper sludge, water purification sludge, municipal sewage sludge, mature compost, superphosphate lime, composite fertilizer, and a viscosity increasing agent composed of a polyacrylic viscosity increasing agent, a polyvinyl viscosity increasing agent, or a mixture thereof. It relates to an artificial culture soil composition and a method for producing the same. Artificial culture soil composition of the present invention has the advantage of maximizing the pH correction effect, maintaining the growth of the plant, increasing the adhesion as well as maximizing the waste recycling effect.

Description

Artificial cultured soil composition and its manufacturing method

The present invention relates to an artificial culture soil composition and a method for producing the same, which is a base composition for planting vegetation on cut surfaces and rock cutouts generated by civil works. More specifically, the present invention is characterized by consisting of paper sludge, water purification plant sludge, municipal sewage sludge, ripe compost, superphosphate lime, composite fertilizer and polyacrylic viscosity increasing agent, while recycling waste, stable to rock walls or cut surfaces The present invention relates to an artificial culture soil composition capable of providing better vegetation conditions and a method for producing the same.

Currently, the disposal of various industrial and household wastes is mostly dependent on landfilling, which is a concern for environmental pollution, and the shortage of landfills is expected to intensify due to local selfishness. Therefore, by supplementing each of the characteristics of water purification sludge, sewage sludge, paper sludge, etc., which have many available components such as clay and organic material, and usefully reusing them, the amount of waste landfill is reduced and the shortage of landfills is eliminated. It is possible to prevent soil and groundwater contamination by leachate, etc., and further economically utilize.

In general, in civil engineering, when the cut surface is ejected, it not only damages the natural landscape but also causes loss of soil due to rainfall, which can cause dangerous accidents, and muddy water flows into the downstream stream, which increases turbidity and adversely affects aquatic plants. Because it hurts, it is necessary to restore them to their natural state. Currently, cultured soils for landscaping rock cuts and cut slopes have been developed and constructed, and the main raw materials are paper sludge, sewage sludge, fly ash and bottom ash.

However, the artificial cultures developed so far have insufficient water supply due to low moisturizing power after construction, and thus, the growth of plants is not smooth, and the phosphate deficiency is caused by pollution of heavy metals eluted from coal ash, and phosphorication by aluminum under acidic conditions. Could cause problems.

In order to solve the above problems, the present inventors have prepared a new artificial culture soil composition by mixing a water purification plant sludge, paper sludge, sewage sludge, mature compost, superphosphate lime, and polyacrylic and / or polyvinyl polymer thickener.

The water purification plant sludge used as the main material of the present invention has a carbon quality ratio (C / N ratio) that is similar to general soils and affects the nutrient absorption of plants, compared to any sludge available so far, and the coal quality of general soils is 11 It is most suitable as an environmentally friendly material in the ratio of 8-12. In addition, water purification plant sludge is a complex of clay and organic material, and has 10 times higher cation exchange capacity (CEC) and 15 times higher organic matter content than coal ash as an alternative material for coal ash. It is favorable to the germination, good germination and rooting of seeds, and little risk of dissolution of heavy metals.

Hereinafter, the characteristics of the present invention will be described in detail.

First, it relates to the adhesion of cultured soil. Cultured soil should be bonded to rock wall incisions to ensure adhesion and durability so that the roots of plants can form mats.However, if the slope is severe or rock walls, existing products will not adhere well and will not be durable and will collapse after construction. Occurred a lot. Conventionally, to solve this problem, CMC (Carboxy Methyl Cellulose) was used by mixing, but C ^{+ (} Al + Ca, Mg, Fe, etc., which contains a large amount of Na ⁺ ions, which is a member of CMC in soil, sewage sludge, and paper sludge) Substitution with cations results in loss of the properties and viscosity inherent in CMC. In the present invention, in order to solve such drawbacks, the adhesion strength was greatly increased by using a water purification plant sludge, polyacrylic and / or polyvinyl viscosity increasing agents.

Water purification plant sludge is an alternative to coal ash.In the particle size distribution according to the triangular coordinate classification method of the International Soil Society and USDA, coal ash contains mainly silt, a substance that causes cracking, and has a clay content of 2-4. Although it is only%, the purified sludge contains 30 to 60% of clay powder, and has superior adhesiveness to coal ash.

Polyacryl-based and polyvinyl-based compounds do not cause a decrease in viscosity and adhesion due to the polyvalent cation, and is easy to mix and inexpensive since it is liquid.

Second is the solution of the heavy metal problem. Coal ash contains Cu, As, Pb, Cr, etc., as defined in the Soil Environment Conservation Act. In particular, Cr contains 150-3,500 ppm. Among them, soluble components can be harmful to plants, so the sludge was used as a substitute for coal ash to solve this problem.

Third is a nutrient supply useful for plants. When comparing the cation exchange capacity (CEC) between coal ash and water purification sludge, coal ash was 4-6 me / 100g, while water purification sludge was 30-45 me / 100g, almost 10 times higher than coal ash. The organic matter content of coal ash was 1.9%, but the water purification plant sludge was 17.9%, 15 times more than coal ash. Such water purification plant sludge is not only a source of inorganic nutrients of plants, but also has an advantage of promoting seeding of soil by organic matter and improving seed germination and rooting.

Fourth, the phosphate deficiency problem is solved by eliminating phytotoxicity of activated aluminum and fixing phosphoric acid of activated aluminum. Water purification sludge, paper sludge, and sewage sludge contain a considerable amount of aluminum because sulfuric acid (Al (SO ₄ ) ₃ ) or polyaluminum chloride is used as a flocculant in the generation process. In general, when the pH of soil is 5.3 or higher, aluminum is inactivated, and the problem of fixing phosphate due to the elution of aluminum can be ignored. (NO _x ), carbon dioxide, carbon monoxide, and sulfur oxides (SO _x ) are adsorbed on the constructed soil, or when the pH of the culture soil is gradually lowered by acid rain, the activated aluminum is absorbed by plants. By inhibiting plant gene replication, it interferes with plant growth and interferes with the absorption of moisture and nutrients, which in turn causes phosphate stabilization, resulting in phosphate deficiency problems. In addition, aluminum accelerates acidification by the following mechanisms.

Al ³⁺ + H ₂ O → Al (OH) ²⁺ + H ⁺

Al (OH) ²⁺ + H ₂ O → Al (OH) ₂ ⁺ + H ⁺

Al (OH) ₂ ⁺ + H ₂ O → Al (OH) ₃ + H ⁺

Under acidic conditions (pH5.3) aluminum is inactivated because aluminum is activated to form a highly stable Al-organic complex with organic acids as components. In addition, the higher the organic content and the lower the pH, the stronger the activity of the organic acid, so in the strong acidic condition of pH 5.3 or less, most aluminum forms a strong complex with the organic acid, so the problem of plant toxicity caused by aluminum can be ignored. The principle for this mechanism is that the organic material is negatively charged and therefore combines with the oxides or hydroxides of aluminum. Therefore, when using a raw material containing a large amount of organic matter, such as water purification plant sludge used in the present invention, a large amount of the organic acid and aluminum complex is produced, it is possible to greatly reduce the toxicity of aluminum.

And in order to solve the problem of phosphate deficiency, which is a phytonutrient caused by the fixation of phosphate caused by the combination of phosphoric acid contained in a large amount of paper sludge and sewage sludge, in the composition of the present invention, superphosphate, a main component: CaH ₄ (PO and mixed with a _{16%]: 4) 2 ·} H 2 O, MW: 252.12, total phosphate: 57.62%, water-soluble phosphate. Superphosphate lime is an acidic fertilizer but does not affect the substitution base of the soil and inhibits the harmful action of active Al ^{3+ in} the soil. In addition, the water-soluble phosphate in the culture soil may bridge the phosphate deficiency due to fixing of the Al ₂ O _3, so by fixing the Al ₂ O ₃ insoluble as follows by mixing the superphosphate of lime.

Al ₂ O ₃ + 2Ca (H ₂ PO ₄ ) ₂ → 2AlPO ₄ + 2CaHPO ₄ + 3H ₂ O

Al ₂ O ₃ + 2H ₂ PO ₄ → 2AlPO ₄ + 3H ₂ O

Fifth, the workability is improved. The countermeasures against activation of aluminum have been used so far to adjust pH with ALC (Autoclaved Light Concrete) sludge.However, ALC sludge has difficulty in adding crushing process to handling and mixing raw materials due to uneven particle size. It was pointed out that it was disadvantageous. The superphosphate lime used as an alternative material has a uniform particle size and does not require a separate crushing process, which is advantageous in construction and economical efficiency.

The artificial culture soil of the present invention was repeatedly tested in the laboratory and on-site, and as a result, water purification sludge 10 to 40% by weight, paper sludge 10 to 40% by weight, sewage sludge 10 to 20% by weight, mature compost 5 to 20 Viscosity increasing agent selected from the weight percent, 0.1 to 3% by weight of the superphosphate lime, 0.1 to 1% by weight of the composite fertilizer, and a viscosity increasing agent composed of a polyacrylic viscosity increasing agent, a polyvinyl viscosity increasing agent or a mixture thereof. It was confirmed that the artificial culture soil composition containing 2% by weight is particularly preferable.

Water purification plant sludge, which is used as a main component in the composition of the present invention, is a collection of various wastes remaining after water purification in a water purification plant. In the present invention, sludge generated in a water purification plant may be used without special processing, but the components may be used as needed. It can also be used by analyzing and cooking.

The paper sludge used in the composition of the present invention may use sludge generated in various paper making processes, for example, paper sludge produced in the process of producing newspaper paper.

Sewage sludge refers to sludge generated after treating municipal sewage, and it is known by various researchers that it can be used as a good plant nutrient in the absence of heavy metals and harmful organic compounds. Although various sewage sludges can be used in the present invention, it is preferable to use sludges produced from municipal sewage containing almost no harmful organic compounds, and in order to protect the environment and safety, the safety of the heavy metal content is analyzed in advance. It is particularly preferable to use the secured one.

In the composition of the present invention, it is preferable to use a fully mature compost having a color Y = 12 or less, a cationic substitution capacity (CEC) of 60 me / 100 g or more, and a C / N ratio of 20 or less.

Lime superphosphate in the composition of the present invention, as described above, by insoluble Al ₂ O ₃ in a cultured soil by insolubilizing by water-soluble phosphoric acid (fixation) to give the effect of preventing the toxicity of aluminum, it is usually commercially available You can use what you have.

Complex fertilizers used in the composition of the present invention, there are a variety of things depending on the use and components, such as red pepper fertilizer, coriander fertilizer, horticultural complex fertilizer, etc., in order to achieve the object of the present invention, It is preferable to use a horticultural compound fertilizer.

The polyacryl-type and / or polyvinyl-type viscosity increasing agent used by the composition of this invention can use a commercially available thing normally.

The method for preparing the artificial culture soil composition of the present invention can be prepared by simply mixing the respective composition components, more preferred manufacturing method is as follows.

Within a range of the composition ratio, paper sludge and municipal sewage sludge are mixed to compost for 20 days. At this time, the composting conditions are mixed with 60 to 65% of water content and 25 to 35 of carbon mass (C / N rate), composting for 20 days, and the first mating is performed. This primary housing process is preferably carried out by a static pile process for 20 days aerobic composting.

The primary raw material and water purification plant sludge, mature compost, composite fertilizer and superphosphate lime and polyacrylic and / or polyvinyl-based viscosity increasing agent is mixed and homogenized to prepare a culture soil.

In the manufacturing method of the present invention, when the composition is left for a long time after mixing, in order to prevent the product from hardening due to the solidification of the viscosity increasing agent, the viscosity increasing agent is preferably mixed immediately before construction.

The artificial culture soil composition of the present invention is constructed in accordance with a conventional method with a predetermined vegetation seeds on various cut surfaces and rock cutouts generated by civil engineering. When explaining the construction method of artificial culture soil of the present invention as follows.

After installation of the attachment net (PVC coating net) on the inclined rock cutout and the cut slope, the moisture content of the cultured soil is adjusted to 65 to 75%, and the weed seeds are mixed and installed to a thickness of about 15 cm by the applicator.

The artificial culture soil composition of the present invention is a result of comparing the commercial maturation compost and physicochemical properties (see Table 1 of Example 3), the pH is neutral, suitable for plant growth, the nitrogen content of the mature compost with a nitrogen content of 1.0% Not only is it higher than (0.4%) but also the fast-acting chemical fertilizer and the organic constituent nitrogen bound to the culture soil material can be properly mixed to facilitate long-term nutrition supply. In addition, the high cation substitution capacity shows very high bond strength. The fertilizer component is adsorbed on the culture soil itself to supply the plant nutrient source for a long time, and to prevent economic loss by preventing rainfall. It can be seen that, less environmental pollution by leachate. In addition, the organic matter content of the water purification plant sludge is 15 times higher than that of coal ash and contains a large amount of clay powder, so the moisturizing power is very large, which can greatly reduce the damage caused by drought.

In addition, as described below, by measuring the phosphoric acid in the Al-P form by mixing the superphosphate lime, the phosphoric acid of superphosphate combined with a large amount of aluminum compared to the case where the superphosphate is not mixed, thereby greatly preventing the toxicity of the aluminum and the lack of phosphate. It can be seen that.

In addition, as a result of experimenting with the germination rate of vegetation in the artificial culture soil composition of the present invention (see Example 4), the germination rate was 93% of the control group showed a germination rate almost the same as the maturity compost. It was confirmed that there are no obstacles such as organic acid and ammonia gas, which are often generated in a mature state. In addition, the root length and the height of the ground above the mature compost is considered to be rich in plant nutrients, such as water-soluble nitrogen, phosphoric acid, kali, which can be easily used by seedlings. It is considered that the initial growth of vegetation after the construction of the culture soil is very important, it can be seen that the artificial culture soil composition of the present invention is excellent.

As a result of observing the artificial culture soil composition of the present invention after construction on rock wall, there was no collapse or drought damage even in rainfall and drought, and in particular, the adhesion was excellent even at right angled rock at 90 °. In addition, as a result of examining the runoff and soil for one year by season whether heavy metals were leaked at the site where the cultured soil was constructed, it was confirmed that it is a very safe product because no harmful substances were detected.

The artificial culture soil composition of the present invention can play a role in restoring the natural environment damaged by various construction works, as well as recycling the waste that is currently socially problematic. In addition, the present invention prevents environmental pollution due to the recycling of waste, solves the shortage of landfills, by using sludge for water purification plant to produce a culture soil closest to the natural soil, using the lime peroxide not existing method This not only solves the toxicity problem of aluminum, but also has the effect of solving the problem of increased adhesion, which was difficult to solve in the conventional method.

The following examples illustrate the invention in more detail, and do not limit the scope of the invention.

Example 1

Based on the total weight of the composition, 40% by weight of papermaking sludge 20% by weight of municipal sewage sludge is mixed and controlled to 60 to 65% of water content and 25 to 35 of carbon quality (C / N ratio), and then composted by forced ventilation. To make the first step. 30% by weight of purified water sludge, 13% by weight of mature compost, 0.2% by weight of lime phosphate, 0.1% by weight of composite fertilizer for grass (nitrogen: phosphoric acid: Kari = 9: 9: 9) Artificial culture soil composition is prepared by mixing 0.04% by weight polyacrylic viscosity increasing agent.

Example 2

Based on the total weight of the composition, 20% by weight of paper sludge, 15% by weight of municipal sewage sludge are mixed and adjusted to 60 to 65% of water content and 25 to 35 of carbon quality (C / N ratio), followed by forced ventilation. Composting is done first. In this primary raw material, 25 wt% of purified water sludge, 13 wt% of mature compost, 1.0 wt% of lime phosphate, 0.3 wt% of grass compound fertilizer, polyacrylic viscosity increasing agent and polyvinyl viscosity increasing agent Artificial culture soil composition is manufactured by mixing 1 weight% viscosity increasing agent mixed at 1: 1.

Example 3: Physicochemical Properties

The artificial culture soil prepared in Example 1 and commercially mature mature compost are shown in Table 1 by measuring the chemical properties in the laboratory.

TABLE 1

As shown in Table 1, the artificial culture soil composition of the present invention was a very suitable condition for plant growth as neutral of pH 7.5. In addition, the nitrogen content is 1.0%, and the fast-acting chemical fertilizer and the organic constituent nitrogen bound to the raw material of the culture soil are properly mixed to facilitate long-term nutrition supply. In addition, the cation substitution capacity was 68 me / 100 g, which was much higher than the ripening compost. This is because CEC of water purification sludge is 10 times higher than coal ash. This proves that the fertilizer is very excellent. Since the fertilizer component is adsorbed on the culture soil itself, there is very little loss due to rainfall. Therefore, it is judged that the loss of material and fertilizer is small and the environmental pollution by acupuncture water is also low. In addition, since the organic matter content of the water purification plant sludge is very high and contains a large amount of clay powder, it can be confirmed that the water holding capacity is very large.

Example 4 Phosphoric Acid Insolubilization Experiment

An experiment was conducted to grasp the phosphoric acid insolubilization by aluminum contained in the composition of the present invention. Water purification plant sludge, paper sludge, sewage sludge, and mature compost were mixed in the same composition as in Example 1, and 100 g (dry weight) was used as Sample A. Sample B was used by adding about 1% by weight of lime superphosphate to 100 g of this sample. These samples were mixed in a 1000 ml Erlenmeyer flask with a ratio of 1: 5 (W / V) of sample and distilled water, and the pH was adjusted to 7, 5.5 and 4 using 0.5 N HCl solution and 0.5 N NaOH solution, respectively. The mixture was shaken for 48 hours.

After shaking was completed, the sample was taken in a plastic container and dried in a 60 ° C dryer. The dried sample was crushed to measure the amount of aluminum bound to phosphoric acid (Al-P) and the results are shown in Table 2 below.

TABLE 2

As a result of this, as the pH decreases, the amount of aluminum eluted increases to cause phosphoric insolubilization of artificial culture soil without mixing superphosphate, but a large amount from the superphosphate lime when mixing the superphosphate lime with the composition of the present invention. It can be seen that phosphoric acid can be combined with free Al ⁺³ to prevent toxicity and phosphoric acid deficiency of aluminum.

Example 5 Germination Rate Test

The germination rate, root length, and ground length of the artificial culture soil composition of Example 1, which is the composition of the present invention, and mature compost were evaluated.

The sample was mixed with distilled water at 1:20 (weight: volume), shaken for 24 hours, and then a certain amount of the filtrate was injected into a petri dish with room for growth. , 25 ° C.), and after 186 hours (7 days) germination rate, root length and ground elongation were measured. This experiment was repeated five times. Distilled water was used for the control experiment. The results are shown in Table 3 below.

TABLE 3

As shown in Table 3, the germination rate of the artificial culture soil composition of the present invention was about 93% of the control group, which showed almost the same germination rate as mature compost. It is judged that the composition of the present invention is free from obstacles such as organic acid and ammonia gas, which are often generated in the immature state, and the root length and the elongation of the ground portion are larger than the mature compost, so that the seedlings are easily available. It is believed to be rich in plant nutrients (phosphate of superphosphate lime, substitutional cations of water purification plant sludge) such as water-soluble nitrogen, phosphoric acid, and girly. This proves that the composition of the present invention is very excellent as the culture soil, considering that the culture soil is very important for the initial growth of vegetation after construction.

Example 6

After attaching the attachment net (PVC coating net) to the inclined rock cutout and cut slope, adjust the moisture content of the culture soil to 65-75%, and then weed seeds and polyacrylic polymer viscosity increasing agent, It was constructed as. After construction, there was no collapse or drought damage in rainfall and drought, especially in the angled rock of about 90 °.

In addition, as a result of investigating whether runoff and heavy metals were leaked by rainfall at the site where the soil was constructed for one year, the amount of harmful to the environment was not detected.

Claims (5)

Water purification sludge, paper sludge, municipal sewage sludge, mature compost, lime superphosphate, compound fertilizer, and a viscosity increasing agent selected from a polyacrylic viscosity increasing agent, a polyvinyl viscosity increasing agent or a mixture thereof. Artificial culture soil composition. The water purification plant sludge is 10 to 40% by weight, the paper sludge is 10 to 40% by weight, the sewage sludge is 10 to 20% by weight, the maturation compost 5 to 20% by weight, the superphosphate lime 0.1 to 3% by weight , 0.1 to 1% by weight of the composite fertilizer and 0.02 to 2% by weight of the viscosity increasing agent. First composting by mixing and composting paper sludge and sewage sludge, the primary raw material and water purification plant sludge, mature compost, lime phosphate, compound fertilizer and polyacrylic viscosity increasing agent, polyvinyl viscosity increasing agent or these Method for producing artificial culture soil, characterized in that for mixing the viscosity increasing agent selected from the viscosity increasing agent consisting of a mixture of. According to claim 3, wherein the longevity sludge is 10 to 40% by weight, the paper sludge is 10 to 40% by weight, the sewage sludge is 10 to 20% by weight, the maturation compost 5 to 20% by weight, the superphosphate lime 0.1 to 3 weight %, 0.1 to 1% by weight of compound fertilizer and 0.02 to 2% by weight of viscosity increasing agent. The method according to claim 3 or 4, characterized in that the first ripening is carried out by mixing paper sludge and sewage sludge so as to have a water content of 60 to 65% and a carbon quality of 25 to 35.