The Technology Research Of Nitro-compound Fertilizer Anti-caking Agent

In the modern production,more than an half energy of planting derives from the chemical fertilizer,which has become a critical condition of crop growth and secure assurance of high yield.However,fertilizer is always facing the problem of caking.This work chooses the nitro-compound fertilizer for the research,which is liable to water absorption,dissolution,agglomeration and so on.Thus,the requirement of developing the reasonable and effective nitro-compound fertilizer anti-caking agents by the anti-caking experimental research.First of all,the internal and external factors of affecting the fertilizer's caking was studied: the mixture of raw materials that make the fertilizer;water content;grain size;environmentally relative humidity;temperature,pressure and storage time;these issues have the vitally guiding meaning to alleviate the caking of fertilizer.Then,two kinds of easily caking nitro-compound fertilizer are used as the experimental fertilizers,accompanying with oil substance as the carrier,producing one anti-caking agent by adding various kinds of surfactants:(1)the anti-caking agent named N-1 of the nitro compound fertilizer(22-8-10)has been developed,whose formula of these five kinds of substances composed of rice bran wax,mineral oil,stearic acid potassium,octadecylamine,octadecanol,of which their ratio is35:5:0.3:2:3,the amount of addition is 0.25%,the anti-caking rate is 88.0%;the effect and cost of as-prepared anti-caking agent are more superior than some commercially available anti-caking agents;(2)the anti-caking agent named N-2 of the nitro compound fertilizer(16-6-18)has been developed,whose formula of these five kinds of substances composed of palm acid oil,rosin,magnesium stearate,fatty alcohol polyoxyethylene ether,amine piece,of which their ratio is40:0.2:0.7:2:3,the amount of addition is 0.25%,the anti-caking rate is 86.0%;the effect and cost of as-prepared anti-caking agent are more superior than some commercial available anti-caking agents;Finally,a preliminary discussion on the mechanism of anti-caking can be deduced from the SEM test.The anti-caking agents fill the gaps or holes,make the surface more smootherand reduce the agglomeration;Hygroscopicity test results show that anti-caking agents can increase the relative humidity and reduce moisture absorption rate,so that the fertilizer is not easy to absorb moisture;The wetting ability experiments show that the anti-caking agents can increase the contact angle between the particles,and the wetting property is reduced,thus lowering capillary adsorption and the agglomeration.