Abstract

Disclosed is a method for preparing a high-solubility nitrogen-phosphorus water-soluble fertilizer, comprising the following steps: step 1: adding phosphoric acid, urea, a curing agent and a polymerization aid into a reactor, stirring the reaction at 70-135 °C for 60-180 minutes to obtain a reaction slurry, and controlling the polymerization rate of phosphorus in the slurry to be 10%-50%; step 2: adding the reaction slurry into a curing device, controlling the temperature of the slurry at 150-220 °C, drying and curing the slurry for 30-90 minutes to obtain a solid material, and controlling the polymerization rate of phosphorus in the dried and cured solid material to be 85%-99%; and step 3: removing the solid material from the curing device and cooling same to 40-70 °C, and then crushing same, so as to obtain a powdery high-solubility nitrogen-phosphorus water-soluble fertilizer. The method is used for quickly preparing the high-solubility nitrogen-phosphorus water-soluble fertilizer, and has the advantage of simple process.

IPC Classes  ?

• C05G 3/00 - Mixtures of one or more fertilisers with additives not having a specifically fertilising activity

Abstract

A method for preparing nutrient-controllable ammonium polyphosphate. The method comprises the following steps: step 1: adding phosphoric acid, urea and a chelating agent to a mixer (1) and reacting under 60-110°C for 10-30 min to obtain a homogeneous liquid material; step 2: uniformly distributing the liquid material on a belt-type polymerizer (4) by means of a material distributor (3), reacting under 150-250°C for 30-120 minutes to obtain a solid material, and then lowering the temperature to 30-60°C; step 3: connecting the tail end of the belt-type polymerizer (4) to a crushing apparatus (6), and the solid material leaves the belt-type polymerizer (4) and directly enters the crushing apparatus (6) for crushing, so as to obtain a powdery material; and step 4: directly packaging the powdery material and using same as a water-soluble solid ammonium polyphosphate product and preparing the powdery material according to a proportion, so as to obtain a liquid ammonium polyphosphate product.

IPC Classes  ?

• C01B 25/40 - Polyphosphates
• C01B 25/44 - Metaphosphates
• C05B 7/00 - Fertilisers based essentially on alkali or ammonium orthophosphates
• C05G 3/40 - Mixtures of one or more fertilisers with additives not having a specifically fertilising activity for affecting fertiliser dosage or release rateMixtures of one or more fertilisers with additives not having a specifically fertilising activity for affecting solubility
• C05G 3/90 - Mixtures of one or more fertilisers with additives not having a specifically fertilising activity for affecting the nitrification of ammonium compounds or urea in the soil
• C05G 5/10 - Solid or semi-solid fertilisers, e.g. powders

Abstract

Disclosed is a method for producing polyphosphate. The method comprises a production system using the following structures, including a premixer, a polymerization reactor, a material distribution device, a cutting device, a crusher, a conveyor and a packaging machine, and comprises the following preparation process: step 1, uniformly mixing a raw material and an additive in proportion in the premixer; step 2, uniformly spraying a liquid material obtained after uniform mixing in the premixer onto a belt conveying assembly of the polymerization reactor by means of the material distribution device, and by means of the belt conveying assembly, conveying the liquid material into a high-temperature area in the polymerization reactor to react for 0.5-2 h, and then into a low-temperature area in the polymerization reactor for cooling, so as to complete a polymer curing process; and step 3, scraping off cured and cooled polyphosphate by means of the cutting device, and entering the scraped polyphosphate into the crusher for crushing. The method is mainly used for rapidly and continuously preparing a polyphosphate, and has the advantages of a high degree of automation and high production efficiency.

IPC Classes  ?

• C01B 25/39 - Condensed phosphates of alkali metals
• C01B 25/44 - Metaphosphates
• B65B 1/06 - Methods of, or means for, filling the material into the containers or receptacles by gravity flow
• B65G 65/32 - Filling devices