A kind of production method of preparing calcium dihydrogen phosphate by-product red bean special fertilizer

Abstract

The invention relates to the field of chemical technique, especially to a production method for preparing monocalcium phosphate and a by-product a special fertilizer for red bean. By changing coefficients such as temperature and the like of wet-process phosphoric acid preparation of monocalcium phosphate, purity of the product monocalcium phosphate is raised, and a compound fertilizer containing N, P and K combined forms can simultaneously be produced. By the method, purity of monocalcium phosphate can be raised, and the produced special fertilizer for red bean has good absorptivity. Meanwhile, formaldehyde is added into a filtrate to prepare a controlled-release compound fertilizer. The produced special fertilizer for red bean can meet nutritional requirements of each period of growth cycle. By the use of the compound fertilizer, yield of red bean is raised greatly. The special fertilizer is an efficient compound fertilizer.

Description

Technical field [0001] The invention relates to the technical field of chemical engineering, in particular to a production method for preparing a special fertilizer for calcium dihydrogen phosphate by-product red beans. Background technique [0002] Adzuki bean (scientific name: Vigna angularis) is a legume plant, also known as red beans and adzuki beans. It is an annual upright or twining herb. The flowering period is summer and the fruit period is September to October. The seeds are used for edible and medicinal purposes. They are often used for cooking porridge and making porridge. Bean paste, the "red beans" mentioned in daily life refers to its fruit. Adzuki beans are preferably compact, purple, and red. Cooking with juice has strong tonic power, and has a very effective effect on reducing swelling and milking. However, long-term eating can make you black, thin and dry. Sowing after the summer solstice, the stems of the bean sprouts are about one foot high, and its branches...

AI Technical Summary

Problems solved by technology

[0008] After the whole reaction is over, the carboxamide does not undergo any changes, and because of the high solubility of carboxamide, at 20°C, its solubility is 85g / 100ml (see "Phosphate Fertilizers and Compound Fertilizers" Volume 20 Issue 6 - Chemistry Fertilizer solubility and compound fertilizer production process), and the solubility of carbonamide increases with the increase of temperature, so after the carbonamide contained in the filtrate is precipitated by cooling crystals, the filtrate also contains a large amount of unprecipitated carbonamide, NH 4 + 、H 2 PO 4 ～ 、HPO 4 2～ 、PO 4 3～ , if the waste water is discharged directly, it will not only waste resources, but also cause waste of resources, and the purity of dipotassium hydrogen phosphate produced is not high

[0009] In the process of producing calcium dihydrogen phosphate from wet-process phosphoric acid, the purity of calcium dihydrogen phosphate is not high, and the filtrate also contains a large amount of unprecipitated carbonamide, NH 4 + 、H 2 PO 4 ～ 、HPO 4 2～ 、PO 4 3～ and other substances, the researchers of the present invention have studied the composition content of traditional corn special fertilizer and the absorption situation of corn from a large number of prior art documents and years of exploration and research, and have effectively explored the production of phosphoric acid diphosphate from wet-process phosphoric acid. The special fertilizer for corn is produced from the filtrate of calcium hydrogen phosphate to solve the problem that the active ingredients in the filtrate of calcium dihydrogen phosphate produced by wet process phosphoric acid cannot be used, etc. There is no report in domestic fertilizer production

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