Abstract: For mobile tank fertilization of row-crop fields, methods and apparatus for improvements in multi-port fluid dispensing. The inventive methods and apparatus allow for replacement of a single regulating valve for the whole multiplicity of spray nozzles with a plurality of self-coordinating, closed-loop controlled, metering valves, but which closed-loop controllers maintain backward compatibility with existing gross flowrate control technology for the now-replaced and omitted single regulating valve. The inventive methods and apparatus can have closed-loop controlled multi-port metering valves for distributing fertilizer fluid to sub-sets of the multiplicity of nozzles, or else a dedicated single closed-loop controlled metering valve for every single one of the nozzles.

Abstract: A condenser that is useful for mobile tank nh3 fertilizer applications is combinable with various options. A single fluid flows into the condenser by an inlet port in a two-phase fluid flow condition (ie., consisting of a vapor phase and a condensate phase) and, during the flow through the condenser, the single fluid cools itself such that for at least a portion of the flow through the condenser, the flow is a single phase flow of condensate only. The preferred single fluid is anhydrous ammonia (NH3). The condenser is combinable with various other options including flow rate measuring, flow rate regulation, flow distribution to multiple outlets, and so on.

Abstract: An anhydrous ammonia fertilizer injector includes a tool bar frame with multiple knife injectors. Vapor pressure of the fertilizer forces liquid from a tank through hoses and a vapor separator to a pump. The pump increases pressure above the vapor pressure. Liquid fertilizer passes from the pump through a flow rate sensor, a servo controller and to a manifold. Discharge fittings on the manifold hold orifices. Discharge hoses convey fertilizer from each discharge fitting to each knife. A pressure transducer in each fitting downstream from the orifice sends current pressure readings to a monitor console. The console identifies the largest number of transducer pressures that have readings within a set pressure difference from each reading. The average of the maximum and minimum pressures identified is the center of an acceptable pressure band. A selected deviation sets band limits. The console displays discharge hoses with pressures outside the band limits.

Abstract: Fluid fertilizer is supplied to a metering assembly by fluid vapor pressure. The assembly divides fluid flow into several equal flows that are injected into the ground. The metering assembly includes a body chamber with a bottom, a top and a cylindrical wall. A driven shaft, journaled in the top wall, extends into the chamber. A rotor is fixed to the drive shaft in the chamber. Pluralities of elongated slots pass through the rotor. Discharge bores pass through a body bottom wall. Each discharge bore includes a counter bore that receives a resilient O-ring and a graphite tube. A top end of the tube engages the rotor on both sides of the elongated slot. The compressed O-ring holds the tube top in engagement with the rotor.