Urea Concentration Profiles from Kokum Wax Coated Briquettes

M.Ramananda Bhat,M.B Saidutta,Sahitya Reddivari,D.V.R Murthy

doi:10.13189/ujar.2014.020201

Abstract

Urea briquettes suffer from major disadvantages such as relatively rapid dissolution, high soil urea concentration around shrinking briquette and susceptibility to leaching losses. Coatings, such as kokum wax applied on the briquettes, can mitigate these problems. Concentrations of urea developed in soil, due to release from kokum wax coated briquettes, were experimentally measured in silt loam soil. High soil urea concentrations as observed in the case of uncoated briquettes were not observed, thereby alleviating the ill effects of high concentration of soil urea.

Highlights

Urea briquettes are used in many of the Asian countries in order to combat some of the disadvantages of surface applied prilled urea, such as leaching losses and surface run off in agricultural fields [1]
Radial soil urea concentrations profiles in the vicinity of shrinking kokum wax coated urea briquettes were experimentally determined to check the effectiveness of coating in attenuating soil urea concentration
In order to investigate the development of concentration profiles around the shrinking kokum wax coated briquettes, urea release experiments were conducted in the silt loam soil maintained at the saturation moisture content of 0.4 g-moisture/g-dry soil (Table 1)

Summary

Introduction

Urea briquettes are used in many of the Asian countries in order to combat some of the disadvantages of surface applied prilled urea, such as leaching losses and surface run off in agricultural fields [1]. The briquettes themselves per se are not of slow release in nature and suffer from some disadvantages such as fast dissolution and high concentration of urea around the shrinking briquettes [2] This high soil urea concentration can lead to burnout of plant roots and adversely affect plant growth. Kokum wax and paraffin wax are two such materials studied from the perspective of urea release [3]. Both the coatings succumbed to rupture and subsequent release form the ruptured locations, it becomes essential to experimentally measure the concentration of urea around the shrinking briquette and compare it with the corresponding urea concentrations from uncoated shrinking briquettes in soil. Radial soil urea concentrations profiles in the vicinity of shrinking kokum wax coated urea briquettes were experimentally determined to check the effectiveness of coating in attenuating soil urea concentration

Materials and Methods

Soil Urea Concentration Profiles

Conclusions