Production method of ammonium sulfate-ammonium phosphate composite fertilizer

Abstract

The invention discloses a production method of an ammonium sulfate-ammonium phosphate composite fertilizer. The composite fertilizer adopts the conventional ammonium phosphate double tubular reactor process; materials required for production mainly comprise strong phosphoric acid with concentration (P2O5) of 40 percent to 48 percent, anhydrous liquid ammonia with high purity and concentrated sulfuric acid with concentration of 90.0 percent to 98.5 percent; the strong phosphoric acid, the liquid ammonia and the concentrated sulfuric acid enter a tubular reactor in a certain ratio according to the specification of the product, neutralization reaction is performed to generate mixed slurry of ammonium sulfate and ammonium phosphate and ammonification and pelletization are carried out by a drum to form the ammonium phosphate-based nitrogen-phosphorus-sulfur (NPS) composite fertilizer. The product disclosed by the invention is rich in nutritional ingredients, such as ammonium nitrogen, soluble phosphate and soluble sulfate, so that the requirements of plant production for nitrogen, phosphorus and sulfur elements are met effectively, the functionality of the ammonium phosphate composite fertilizer is expanded, the added value of the product is improved, and an effective way is provided for promoting diversification of the fertilizer product.

Description

technical field [0001] The invention relates to the field of fertilizers, in particular to a production method of ammonium phosphate compound fertilizer containing sulfur elements. Background technique [0002] Diammonium phosphate is a binary quick-acting compound fertilizer that contains nitrogen and phosphorus, two essential nutrients for plant production. Facing the impact of overcapacity and severe market saturation, it is imperative for fertilizer manufacturers to pursue a differentiation strategy. The diammonium phosphate production process and product quality are single, and its binary compound fertilizer has certain limitations. With the rise and wide application of the multi-component compound fertilizer industry and the progress of its technology, it is urgent to improve and optimize the ammonium phosphate production process to form compound fertilizers containing various specifications of trace elements, expand product types, and improve product quality. [000...

AI Technical Summary

Problems solved by technology

[0004] At present, there are some methods of producing sulfur-containing fertilizers in China, but the main production of sulfur-containing compound fertilizers is through the addition of simple sulfur, such as sulfur in a molten state, as a production method, or by wrapping and coating, or by blending into slurry. In this way, sulfur enters the chemical fertilizer in liquid form, and under high temperature and high pressure in the chemical industry, sulfur is a flammable and explosive solid. There are certain risks in the production process, and complex process design is required to ensure the safety of the process.

In addition, elemental sulfur is insoluble in water, and the efficiency of direct absorption by plants is generally reduced

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