Production method for preparing monocalcium phosphate byproduct used as special fertilizer for chives

Abstract

The invention relates to the technical field of chemical engineering, particularly to a production method for preparing a monocalcium phosphate byproduct used as a special fertilizer for chives. A fertilizer required by the chives is analyzed, nutrient elements contained in a residual waste liquid in a preparation technology of a monocalcium phosphate product are analyzed, preparation of the monocalcium phosphate product and preparation of the special fertilizer for the chives are organically combined together, the discharged waste liquid amount is reduced, a large amount of waste of nitrogen, phosphorus and calcium elements is avoided, and the crystallization separation amount of monocalcium phosphate in a monocalcium phosphate crystallization separation step is controlled, so that deep crystallization separation is unnecessary, the purity of the monocalcium phosphate product is further increased to be higher than 97.1%, and the cost for purifying the monocalcium phosphate product in the traditional preparation technology of the monocalcium phosphate product is reduced.

Description

technical field [0001] The invention relates to the technical field of chemical industry, in particular to a production method for preparing calcium dihydrogen phosphate by-product leek special fertilizer. Background technique [0002] Chives are cultivated for the purpose of harvesting seedlings. The growth period experienced is mainly the seedling stage, and multiple crops can be cultivated in a year. According to the color of its leaves grown under light and no light conditions, it is divided into green garlic and garlic yellow. Generally, the planting density of chives is relatively high, and more fertilizers can be absorbed per unit area, while the garlic cloves of chives are small and require a large amount of nutrients from the soil, so the soil is fertilized more. At the same time, the edible parts of chives are stems and leaves, so Chives are required to be tender, juicy and delicious, so the preparation of special fertilizer for Chives has become an imperative ste...

AI Technical Summary

Problems solved by technology

It can be seen that in the prior art, there are relatively few preparations and researches on the special compound fertilizer for chives, and some researches are also mixed compound fertilizers formed by mixing various chemical fertilizers and organic matter according to traditional techniques. During the preparation process of fertilizers, the combination of nitrogen, phosphorus and potassium elements will be unbalanced, and it will be difficult to satisfy the absorption of nitrogen, phosphorus and potassium elements by crops such as leeks in proportion to the absorption ratio of the crops, resulting in some elements being completely absorbed. Another kind of element remains in the soil, and it will be eroded and biochemically with other elements in the soil for a long time, which will lead to changes in the nutrients in the soil structure layer, and then cause pollution of the soil layer. The cumulative application of this fertilizer input, it will lead to serious pollution, which in turn poses a serious threat to the ecology

[0004] At the same time, in the preparation process of dicalcium hydrogen phosphate products, it is usually prepared by raw materials obtained by wet-process phosphoric acid, and also by raw materials obtained by hot-process phosphoric acid, so a large amount of impurity elements will remain in the phosphate rock. The purity of the prepared calcium dihydrogen phosphate product is relatively low, and it is difficult to meet the needs of the use. For this reason, some researchers generate an intermediate by using phosphoric acid and urea to react, and then use this intermediate to carry out the crystallization of the calcium dihydrogen phosphate product. Further The purity of calcium dihydrogen phosphate is greatly improved, but the calcium dihydrogen phosphate obtained in the preparation process needs to be subjected to deep crystallization treatment, so as to avoid the waste of various elements in the raw material solution and reduce the production cost of calcium dihydrogen phosphate At the same time, it will lead to a decrease in the purity of the calcium dihydrogen phosphate product, and at the same time, a part of the nitrogen, phosphorus and calcium elements will be discharged into the environment in the waste liquid, causing environmental pollution. Research and discuss the fertilizer requirement during the growth process, and according to the detection and analysis of the waste liquid in the preparation process of calcium dihydrogen phosphate products, through the adjustment and matching of nutrient elements in the waste liquid, calcium dihydrogen phosphate and The preparation process of special fertilizer for chives provides a new idea

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