The principal aim of this research is to study the affecting factors the design of a portable chemical (fertilizers, pesticides, and anti-clogging agents) injection unit (CIU) powered with engine, and evaluate the designed (CIU) with pressurized irrigation system, for easy operation and maintenance of chemigation application to cover growers/irrigation designers needs for efficient (CIU) with independent power supply, using an economical materials available in thelocal market, and to add the designed (CIU) as a choice in expert system program help in proper selection of (CIU) according to field conditions, and to overcome field chemigation problems in pressurized irrigation system at many farms such as; unavailable power source, limited irrigation quantity and time period, long or large main line distance/size and improper field location to water source and irrigation pump. In addition, the designed chemigation injection unit (CIU) is compared with other fertilizer injectors available in the local market.
The main results in this study can be summarized in the following:
* Average injection rate ranged from 0.1 to 0.25 m3/h, for imported injectors, and 0.1 to 1.2 m3/h for developed CIU. Injection pressure ranged from 2 to 4 bar. (200 - 400 kPa) and from 0.5 to 4 bar. (50 - 400 kPa) for imported injector and developed CIU respectively.
* The average uniformity of injection rate was 99 % during chemigation time for developed injection unit .
* Economical verification of the feasibility of using the developed and imported injectors is discussed.