Design and development of pressurized aqueous fertilizer application system for seeder

Abstract

In dry land areas, seed germination greatly affected by insufficient soil moisture during sowing. Nitrogenous fertilizers like granular urea remain unavailable due to inadequate soil moisture to dissolve, dilute and convey it to root zone level. Precise application of aqueous fertilizer at root zone depth at the time of sowing enhances seed germination percentage by increasing available soil moisture as per the soil-moisture-crop requirement. A pressurized aqua ferti metering system was designed and developed for application of aqueous fertilizer diluted with water along the side of seed. The prototype consisted of pressurized aqueous fertilizer metering system through positive displacement pump, stationary opening with agitator type seed metering system and shovel type furrow opener with provision of carrying seed and aqueous fertilizer delivery tubes. A pressurized aqueous fertilizer application system consisted of rotary gear pump to vary pump rotational speed and circular distributor for uniform distribution of aqueous fertilizer. The flow rate and pressure were controlled by control valve for required amount of aqueous fertilizer. Three nozzles of size 8, 10 and 12 mm were evaluated at different pump rotational speeds (1800, 1440, 1152, 1080 and 864 rpm) and different control valve positions (0, 2, 4 and 6 kg/cm2 ) for desired flow rate. The discharge rate at a particular pressure was found to vary linearly with the Pump rotational speed and decreased as the line pressure increased. The desired flow rate in pressurized pumping system was obtained in a nozzle of size 10 cm up to a maximum pump speed of 1440 rpm and for a line pressure of less than 4 kg/cm2 .