Liquid fertilizers

Manure is often recycled as a solid organic fertilizer or mixed with water and sprayed as a liquid fertilizer. If the manure is repeatedly used upwind of populated areas, complaints are sure to be filed with the air pollution control agency. 

Dihexyl sulfosuccinate is used to improve the wetting and spreading characteristics of water-soluble pesticide sprays. In liquid fertilizers, insecticides, and fungicides, dioctyl sulfosuccinate will increase their penetrating ability. 

Application methods Usually as water spray or in liquid fertilizers applied preemergence, but also may be applied preplant or postemergence. Rates of 2-4 pounds/acre (2.24-4.48 kg/ha) are effective for most situations higher rates are used for nonselective weed control, and on high organic soils... 

Liquid fertilizers, potassium orthophosphates in, 20 637 Liquid-film coefficient, 15 695 Liquid filtration, 11 322-323 Liquid flavor forms, 11 576-577 Liquid flow control, in variable-conductance heat pipes, 13 233 Liquid fluidization, 11 791-792 Liquid food ingredients, encapsulated,... 

A weekly dose of high-potash organic liquid fertilizer see pp.l94-195) is necessary for flowering plants and tomatoes. For baskets of herb plants, use a general-purpose liquid fertilizer every two weeks. Seaweed extract added to the fertilizer can be beneficial. 

When buying liquid fertilizers, choose those with an organic symbol of approval if available. They may be formulated as balanced products for general use, or with a high potash... 

Feed with a general or potash-rich liquid fertilizer (see pp.194-195) as appropriate. Seaweed extract will give plants a boost. 

A 3 1 molar ratio of ammonia and carbon dioxide (excess ammonia) are heated in the autoclave for 2 hr at 190°C, and 1500-3000 psi. The mixture formed is approximately 35% urea, 8% ammonium carbamate, 10% water, and 47% ammonia. It is cooled and the ammonia is distilled at 60 °C. The residue from the ammonia still enters a crystallizer at 15°C. More ammonia is removed by vacuum. The resulting slurry is centrifuged to get solid urea. All excess nitrogenous materials from the liquid are combined and processed into liquid fertilizer, which contains a mixture of all these materials. 

Urea is used in solid fertilizer (54%), liquid fertilizer (32%), livestock feed (7%), urea-formaldehyde resins (5%), melamine (1%), and... 

The breakdown of the use of potassium hydroxide is as follows potassium chemicals (35%), potassium carbonate (25%), liquid fertilizer (12%), soaps (12%), and potassium phosphates (7%). 

There are many different types of liquid and solid fertilizers but we give only some generalizations about advantages of each. Liquid fertilizers are a clear solution, a suspension of a solid in a liquid (aided by a suspending agent), or a simple slurry of a solid in a liquid. Solid fertilizers contain no liquid. Table 21.3 summarizes the advantages of liquids and solids. 

Mixed solid fertilizers can be made by either direct granulation methods (40%) or bulk blending (40%). Bulk blending is made by mechanical mixing of the separate granular intermediate materials. It is usually done in small plants near the point of use. This technique is employed because the fertilizer can be tailor-made to fit the exact requirements of the user. Fluid or liquid fertilizers (clear, suspension, and slurry) account for 20% of all NPK mixed fertilizers. 

Diaiomite has only weak adsorption powers but shows excellent absorption because of its structure and high surface area. Acids, liquid fertilizers, alcohol, water, oils, and other fluids are absorbed by diatomite. 

UREA-AMMONIUM POLYPHOSPHATE. A fertilizer similar fo urea-ammonium othtrophosphate except that about half the phosphorus is in polyphosphate form, which gives improved sequestering action and solubility. It is excellent for use as a liquid fertilizer. 

The U.S. urea production from 1976 to 1980 (18,19) is given in Table 8. During this period, urea became the most important solid nitrogen fertilizer. Urea solution production almost doubled from 1977 to 1978, proving its importance as a liquid fertilizer... 

A Study of Potassium Mono-, Di-, and Triphosphate Heterogeneous Systems in Views of Their Use as Liquid Fertilizers... 

Potassium hydroxide is used for the production of potassium carbonate, tetrapotassium pyrophosphate and other potassium phosphates, liquid fertilizers, and soaps. 

Urea is used as a solid fertilizer, a liquid fertilizer and miscellaneous applications such as animal feed, urea, formaldehyde resins, melamine, and adhesives. Presently, the most popular nitrogen fertilizer is a urea-ammonium nitrate solution. Urea-formaldehyde resins have large use as a plywood adhesive. Melamine-formaldehyde resins are used as dinnerware and for extra-hard surfaces (Formica ). The melamine is synthesized by condensation of urea molecules. 

Commercial grades of AN include solutions that contain about 83% AN and solid products. Both grades are used for direct fertilizer applications, or they are blended with other materials to form mixed solid and liquid fertilizers. High density, prilled AN is usually used for direct applications while other solid AN is mixed with phosphate and potash for multi-nutrient fertilizers. Solid AN has lost market share to urea because it has a lower nitrogen content (33-35% for AN vs. 45-46% for urea), plus it costs more per ton. In addition to direct application, AN solutions are mixed with urea to make nitrogen solution fertilizers240. 

The concentration and the solidification of ammonium nitrate and urea solutions to form solid fertilizers require considerable expenditure of eneq>y and processing expense so it is attractive to use the solutions in the formulation of liquid fertilizers, without processing them into solid form. However, neither ammonium... 

Fig. 24.22. Liquid fertilizer mix plant. (Source Fertilizer Manual.)...

Formulation scientists usually formulate their product to be used alone in water. The potential of tank mixes or the use of liquid fertilizers as a carrier liquid is considered later in the formulation development process. Obviously, the environment a formulation will encounter in use is very different when it is mixed with one or more agrichemicals as compared to the formulation being mixed in pure water. Rather than having one active ingredient present with surfactants carefully selected to disperse that formulation, two or three active materials with six or eight different surfactants may be present in the spray tank. No wonder there are incompatibilities ... 

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