Soil conditioner containing potassium phosphorite and potassium feldspar and preparation method thereof

Abstract

The invention discloses a soil conditioner containing potassium phosphorite and potassium feldspar and a preparation method of the soil conditioner. The preparation method comprises the following steps: firstly, crushing and grinding the potassium phosphorite and the potassium feldspar, and then sieving; drying calcium carbonate, crushing and sieving; mixing the treated potassium-containing phosphorite, potassium feldspar and calcium carbonate in proportion to obtain a mixed material, calcining the mixed material to obtain a sintered clinker, naturally cooling, crushing, grinding and sieving to obtain the soil conditioner. According to the invention, potassium-containing phosphorite, calcium carbonate and potassium feldspar are mixed and fired to prepare the soil conditioner for the first time, so that environmental protection benefits and economic benefits are achieved, and meanwhile, the scientific concept of circular economy is embodied; the sintered clinker is not subjected to water quenching cooling and drying treatment, water resources are saved, energy used for drying is saved, and the produced product can improve the soil structure, supply nutrients to crops, inhibit soil pathogen transmission and remarkably improve the soil fertility. The product contains various nutrients and has long fertilizer efficiency, effective components are not easy to lose, and slow and long-acting supply can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of environmental protection and chemical production, and more particularly to a soil conditioner containing potassium phosphate ore and potassium feldspar and a preparation method thereof. Background Art

[0002] Among the phosphate resources, more than 90% are medium-low grade phosphate ores, most of which are difficult-to-select collophanites. At the same time, potassium resources are also very scarce. Therefore, how to make full use of and develop the existing medium-low grade potassium phosphate ores is one of the effective ways to develop phosphorus-potassium compound fertilizers. Sichuan Hanyuan potassium phosphate mine is the largest new type of symbiotic deposit containing phosphorus and potassium discovered in my country, with a census reserve of 2 billion tons. The main mineral components are collophanites and potassium feldspar. The mine is a medium-low grade phosphorus-potassium mine, and the content of other impurities in the minerals, such as iron, aluminum, and magnesium, is relatively high. Making full use of Sichuan Hanyuan potassium phosphate mine is of great significance to promoting the development of the western region and the development of phosphorus-potassium fertilizers.

[0003] In addition to the three major nutrients of nitrogen, phosphorus and potassium, calcium, magnesium, sulfur and other medium elements also play an important role in the growth of plants. They are the main components of cell walls, chlorophyll, proteins and nucleic acids, and directly affect the life processes of plant cells, photosynthesis and protease synthesis. In recent years, with the continuous increase in production levels and the large-scale application of nitrogen, phosphorus and potassium fertilizers, the medium elements in the soil can no longer meet the needs of crops. Fruit trees and vegetables lack medium elements, and various physiological diseases frequently occur, seriously affecting the yield and quality improvement. This requires the application of a large amount of soil conditioners containing calcium, magnesium, sulfur and other elements.

[0004] Chinese patent document CN103086779A discloses a method for producing alkaline fertilizer using phosphate tailings or low-grade phosphate ore by blast furnace method, wherein the phosphate tailings or low-grade phosphate ore are mixed with insoluble potassium-containing rocks, and then coke or anthracite is added, and the mixture is ground and water is added to form a block, which is then roasted at 1000-1200°C for 30-150 minutes, and the obtained sintered clinker is water quenched, drained, dried, and crushed to obtain an alkaline fertilizer. The invention has a simple process and strong operability, but the water quenching and drying process consumes a lot of water resources and energy.

[0005] Chinese patent document CN101544518A discloses a method for producing potassium calcium fertilizer using potassium feldspar, limestone and phosphogypsum, which belongs to the field of three wastes treatment and chemical production technology. The method mixes potassium feldspar, limestone and phosphogypsum in a certain mass ratio, grinds, makes balls or blocks, and then roasts them in a rotary kiln, a vertical kiln or a tunnel kiln. The sintered clinker is crushed and packaged into a potassium calcium fertilizer product. The potassium calcium fertilizer of this invention contains more nutrients than the potassium calcium fertilizer of other patent inventions, contains a medium amount of sulfur, but does not contain the important element phosphorus, and cannot meet the demand of crops for fertilizer nutrient phosphorus.

[0006] At present, there are no reports on the use of potassium-containing phosphate rock, calcium carbonate and potassium feldspar to burn soil conditioners, and there is a lack of reasonable utilization methods for potassium-containing phosphate rock and phosphorus-containing solid waste. Summary of the invention

[0007] In view of this, in view of the current situation that there is no rational utilization of potassium-containing phosphate ore and phosphorus-containing solid waste in the prior art, there are few types of nutrients in alkaline fertilizers such as potassium-calcium fertilizers, silicon-calcium-potassium fertilizers, silicon-calcium-magnesium-potassium fertilizers on the market, and crops have an urgent demand for secondary elements, the present invention provides a method for calcining a soil conditioner with potassium-containing phosphate ore, calcium carbonate and potassium feldspar.

[0008] To achieve the above object, the present invention adopts the following technical solution:

[0009] First, the present invention provides a method for preparing a soil conditioner containing potassium phosphate rock and potassium feldspar, comprising the following steps:

[0010] S1. crushing, grinding and sieving the potassium phosphate ore and potassium feldspar;

[0011] S2. The calcium carbonate is dried and crushed and sieved;

[0012] S3. The potassium-containing phosphate rock and potassium feldspar treated in step S1 and the calcium carbonate treated in step S2 are mixed in proportion to obtain a mixed material;

[0013] S4. The mixture is calcined to obtain a sintered clinker;

[0014] S5. Cool the roasted clinker naturally, and obtain the soil conditioner by crushing, grinding and sieving.

[0015] Preferably, the drying temperature in step S2 is 30-60° C. and the drying time is 1-3 hours.

[0016] Preferably, in step S3, the mass ratio of potassium phosphate ore, potassium feldspar and calcium carbonate is (0.6-1.6):(1.2-2.2):(0.6-1.6).

[0017] Preferably, the calcination conditions of the mixed material in step S4 are: first calcining at 900-1100° C. for 0.5-2 h, then heating to 1100-1200° C. and continuing calcining for 0.5 h.

[0018] Preferably, in step S5, the temperature is cooled to 20-50°C.

[0019] Preferably, in step S5, the product is sieved through a 20-100 mesh sieve.

[0020] In addition, the present invention also provides a soil conditioner containing potassium phosphate rock and potassium feldspar prepared by the above technical solution.

[0021] It can be seen from the above technical solution that, compared with the prior art, the present invention discloses a soil conditioner containing potassium phosphate ore and potassium feldspar and a preparation method thereof, which has the following beneficial effects:

[0022] The present invention is the first to mix potassium phosphate ore, calcium carbonate and potassium feldspar to prepare a soil conditioner, which has both environmental protection benefits and economic benefits, and also embodies the scientific concept of circular economy. Moreover, the sintered clinker of the present invention does not need to be cooled by water quenching or drying, which saves water resources and energy used for drying.

[0023] The soil conditioner produced by the present invention can adjust the acidity and alkalinity of the soil, improve the soil structure, prevent the soil from being compacted, and not only supply nutrients to crops, but also can be used as a soil salt base to enhance the salt tolerance of crops, promote the decomposition and transformation of organic matter in the soil, and inhibit the spread of soil pathogens, etc., and can significantly improve soil fertility by continuous use; the present invention contains many types of nutrients, including phosphorus, potassium, silicon, calcium, magnesium and other nutrients, has a long fertilizer effect, and the effective ingredients are not easy to be lost, and can be slowly and long-term supplied to crops for absorption; the present invention has low production cost and simple production process, and is easily accepted by farmers and used in large quantities. DETAILED DESCRIPTION

[0024] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Example 1

[0026] Preparation of soil conditioner containing potassium phosphate rock and potassium feldspar:

[0027] S1. crushing and grinding the potassium phosphate ore and potassium feldspar and passing through a 100-mesh sieve;

[0028] S2. The calcium carbonate was dried at 50°C for 2h and then crushed through a 100-mesh sieve;

[0029] S3. The potassium phosphate ore, potassium feldspar and calcium carbonate are mixed in a mass ratio of 1:1.5:0.8 to obtain a mixed material;

[0030] S4. The mixture was calcined at 950°C for 0.6h, then heated to 1100°C and calcined for 0.5h to obtain a sintered clinker;

[0031] S5. Cool the sintered clinker naturally to 25-30°C, crush, grind and sieve to obtain the soil conditioner.

[0032] According to the test, the conversion rate of potassium in the potassium ore in the prepared soil conditioner reached 90.2%. 2 O 5 、A1 2 O 3 、SiO 2 , CaO and MgO are transformed into effective ingredients that can be absorbed by crops, and the total content of effective ingredients reaches 78.8%.

[0033] Example 2

[0034] Preparation of soil conditioner containing potassium phosphate rock and potassium feldspar:

[0035] S1. crushing and grinding the potassium phosphate ore and potassium feldspar and passing through a 100-mesh sieve;

[0036] S2. The calcium carbonate was dried at 60°C for 1 h and then crushed through a 100 mesh sieve;

[0037] S3. The potassium phosphate ore, potassium feldspar and calcium carbonate were mixed in a mass ratio of 0.6:1.2:0.6 to obtain a mixed material;

[0038] S4. The mixture was calcined at 1000°C for 1h, and then the temperature was raised to 1100°C and calcined for 0.5h to obtain a sintered clinker;

[0039] S5. Cool the sintered clinker naturally to 25-30°C, crush, grind and sieve to obtain the soil conditioner.

[0040] Example 3

[0041] Preparation of soil conditioner containing potassium phosphate rock and potassium feldspar:

[0042] S1. crushing and grinding the potassium phosphate ore and potassium feldspar and passing through a 100-mesh sieve;

[0043] S2. The calcium carbonate was dried at 30°C for 3h and then crushed through a 100-mesh sieve;

[0044] S3. The potassium phosphate ore, potassium feldspar and calcium carbonate were mixed in a mass ratio of 1.6:2.2:1.6 to obtain a mixed material;

[0045] S4. The mixture was calcined at 1100°C for 0.5h, and then the temperature was raised to 1200°C and calcined for 0.5h to obtain a sintered clinker;

[0046] S5. Cool the sintered clinker naturally to 25-30°C, crush, grind and sieve to obtain the soil conditioner.

[0047] In the technical solution of the present invention, the main component of the collophosphite in the potassium-containing phosphate ore is CaMg(CO) 3 and Ca5 F(PO 4 ) 3 , CaMg(CO) 3 After high-temperature calcination, it decomposes into calcium oxide, and potassium feldspar undergoes quasi-vitrification. The potassium ions in it are in a high-energy activation state. Under suitable conditions, calcium oxide continuously replaces the potassium ions in the quasi-vitrified potassium feldspar. At the same time, calcium carbonate reacts with potassium feldspar to increase the conversion rate of potassium in potassium feldspar. The main component of phosphate tailings, Ca 5 F(PO 4 ) 3 After potassium feldspar undergoes quasi-vitrification, it forms a silicate glass network with it, and the nutrient phosphorus in it can be slowly dissolved in the soil.

[0048] Experimental example

[0049] This embodiment is a potted plant experiment.

[0050] Soil from the same region was weighed and passed through a 20-mesh sieve into a plastic flower pot, and the soil conditioner produced in Example 1 was applied thereto in an amount of 1.5% of the soil mass.

[0051] A blank test was arranged during the same period, that is, no soil conditioner products were used, and the results are shown in the following table:

[0052]

[0053]

[0054] The above results show that the pH of the soil conditioner produced by the present invention is significantly increased after use, and the other indicators are improved. The alkaline factors such as calcium, magnesium, and aluminum in the soil conditioner of the present invention are hydrated in the soil and the pH is between 7 and 9, providing a weakly alkaline environment, while retaining soluble sulfate and citric acid-soluble phosphorus, expanding the application range of the soil conditioner, and can effectively improve the soil structure, prevent soil compaction, and provide sufficient nutrients.

[0055] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0056] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a soil conditioner containing potassium phosphate rock and potassium feldspar, characterized in that: The following steps are involved: S1. crushing, grinding and sieving the potassium phosphate ore and potassium feldspar; S2. The calcium carbonate is dried and crushed and sieved; S3. The potassium-containing phosphate rock and potassium feldspar treated in step S1 and the calcium carbonate treated in step S2 are mixed in proportion to obtain a mixed material; S4. calcining the mixture to obtain a sintered clinker; S5. Cool the roasted clinker naturally, and obtain the soil conditioner by crushing, grinding and sieving.

2. The method for preparing a soil conditioner containing potassium phosphate ore and potassium feldspar according to claim 1, characterized in that: The drying temperature in step S2 is 30-60° C. and the drying time is 1-3 hours.

3. The method for preparing a soil conditioner containing potassium phosphate ore and potassium feldspar according to claim 1, characterized in that: In step S3, the mass ratio of potassium phosphate ore, potassium feldspar and calcium carbonate is (0.6-1.6):(1.2-2.2):(0.6-1.6).

4. The method for preparing a soil conditioner containing potassium phosphate ore and potassium feldspar according to claim 1, characterized in that: The calcination conditions of the mixed material in step S4 are: first calcining at 900-1100° C. for 0.5-2 h, then heating to 1100-1200° C. and continuing calcining for 0.5 h.

5. The method for preparing a soil conditioner containing potassium phosphate ore and potassium feldspar according to claim 1, characterized in that: In step S5, the mixture is cooled to 20-50°C.

6. The method for preparing a soil conditioner containing potassium phosphate rock and potassium feldspar according to claim 1, characterized in that: In step S5, the product is sieved through a 20-100 mesh sieve.

7. A soil conditioner containing potassium phosphate rock and potassium feldspar prepared by the method according to any one of claims 1 to 5.

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