| 摘要 |
<p>Producing a dust-free granular anur which slowly liberates nitrogen Process comprises dehydrating waste organic compost so as to produce small particles, mixing these dehydrated particles with a phosphorus source, a potassium source and a urea in that order to obtain a mixture of uniform chemical compn. and grain-size, mixing this with an aq. soln. of formaldehyde of a urea, in which there is excess formaldehyde so that a formaldehyde urea prepolymer has been formed, to form a damp mass of uniform chemical compn. adding an aq. mineral acid to produce a broth, stirring this vigorously and eliminating water from this broth to produce the desired manure.</p> |
