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Review of Venturi Injector Application Technology for Efficient Fertigation in Irrigation System

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Int.J.Curr.Microbiol.App.Sci (2020) 9(1): 46-61 International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 9 Number 1 (2020) Journal homepage: http://www.ijcmas.com Review Article https://doi.org/10.20546/ijcmas.2020.901.006 Review of Venturi Injector Application Technology for Efficient Fertigation in Irrigation System Rajab Omary1, 2, Hong Li1*, Pan Tang1, Zakaria Issaka1, 3 and Chen Chao1 1Research Centre of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang, Jiangsu 212013, People’s Republic of China 2Economic and Productive Sector, Dar es Salaam Regional Commissioner’s Office, Ministry of Agriculture, Food Security & Cooperatives, Dar es Salaam 12880, Tanzania 3Department of Agricultural Engineering, Tamale Technical University, Northern Region, Tamale, Ghana *Corresponding author ABSTRACT K e yw or ds The venturi injector has been used widely in different sizes of irrigation venturi injector, system as one of the main fertilization devices. The venturi injector plays application, great roles in the quality of crop production especially, integration with technology, fertigation, irrigation system. In this paper, some of the major limitations associated irrigation system with the operation of the venturi injector has been highlighted. These major difficulties found are unstable suction flow, backflow, and critical Article Info cavitation. These limitations affect the hydraulic performance of venturi Accepted: injector by reducing the efficiency or total working performance. The 15 December 2019 Available Online: future work suggestions for further upcoming research concentration were 20 January 2020 presented for improvement of agriculture field. Introduction create a negative pressure relative to atmospheric pressure (Barber, 1962; Ben Venturi injector is a tapered constriction Asher et al., 1974; André et al., 1978b; Bar faucet which operates on the principle that Yosef, 1999). pressure drops accelerate the change of velocity of the water as it passes through the A venturi injector does not depend on the constriction. In order for the solution to flow external power for its operation. Venturi from a tank into the injector, the pressure structure has no moving parts, which increases drops through the venturi must be sufficient to its life and decreases the probability of 46 Int.J.Curr.Microbiol.App.Sci (2020) 9(1): 46-61 failure (Wang, 2006; Wang et al., 2006; Sun, Singh, 2002). From the conventional mode of 2010; Sun and Niu, 2010; Yan and Chu, application, fertigation has gradually 2011). Usually, the venturi injector transformed into the management of required constructed with plastic materials which water and nutrients. ( Meng, 2006; Yan et al., makes it resistant to most reactive 2010). It converts way and method of chemicals (Richardson, 1987; Yeager and irrigation from solid fertilizer application Henley, 1986). It requires low cost, minimal directly to the farm towards the fertilizer operator attention and maintenance compare applied directly to crops through irrigated to other equipment with similar functions and water (Scaife and Bar-Yosef, 1995; Imas, operating capability (Clark et al., 1991; FAO, 1999). 1993). It is easy to adapt to most popular irrigation system such as drip and sprinkler It could save an amount of water with irrigation system, provided a sufficient fertilizer use efficiency, reduce labor and pressure differential can be created (Hartz and become economic management, improve land Hochmuth, 1996). utility and ensure nutrient supply (Singh, 2002). Fertigation makes environment Venturi injector can be differentiated by size protection balanced as a result of soil and can be operated under different pressure conditions, crops outcomes of agricultural condition. The specific model of venturi products improved (Neto and Porto, 2004). injector will affect the suction capacity (injection rate), head loss required and the Fertigation supported by the fertilizer types of range of working pressure (Janos, 1995).The equipment in order to achieve the performance level of supply tank drop also is among the of water and fertilizer in the field (Kessler et factors which will decrease the injection rate. al., 2004). Venturi injector is a common (Papadopoulos, 1993). device used in fertigation for different size of the farms (Gao et al., 2015). The geometrical parts of venturi injector are divided into three main sections such as a It is used in macro and micro-irrigation convergent section (nozzle), followed by systems due to its numerous advantages throat section (constant part), ending with compared with pressure depending fertilizer diffuser section. The geometrical parts can tank, water injection pump, and electric easy identified by geometrical variables such injection pump (Johnson et al., 1986; Reader- as diameters, convergent length and angle, and Harris et al., 2001; Manzano andPalau, 2005). the diffuser length and angle (Weiler and Sailus, 1996; Dimitrios et al., 2014). The macro and micro-irrigation system with injected fertilizers has less cost than broadcast Irrigation and fertigation system approach, soluble fertilizer, herbicides, and fungicides can be applied easily into irrigation Fertigation is the way of dissolving the water and with little extra equipment (Sciaroni appropriate concentration of fertilizer in et al., 1957; Black, 1968). irrigation water by specified irrigation system (Keller and Bliesner, 1990; Mondal and The fertigation must be under these Tewari, 2007; Kafkafi and Tarchitzky, 2011). considerations: Size and complexity of The irrigated water with nutrient together is nursery, water flow rate, injection ratio and the important requirement of the farm input mobility (Hofman and Van Cleemput, 2004). for increasing crop production. (Wahid, 2000; The fertigation model determine by which 47 Int.J.Curr.Microbiol.App.Sci (2020) 9(1): 46-61 additional equipment is needed such as valves, Integrated fertigation with irrigation pressure and flow, regulators, but the basics system equipment’s for complete fertigation system must be fertigation device (Venturi injector) The knowledge of integrated venturi injector (Steven,2008). The concentration of the stock with the system of irrigation in the world is solution in fertilizer tank, filter, Non-Return the quickly spreading, as the rapid Valve (NRV) and water meter, also flushing development of irrigation system and after fertigation for prevention of corrosion fertigation technologies (Sha et al., 1995). and microbial growth in the irrigation system However, the performance and accuracy of (Nir, 1982; Papadopoulos, 1988; Smajstrla et fertigation reduced by the low efficiency of al., 1991; Burns, 1998;; Hanson et al., 2006; fertigation devices such as venturi injector. Jensen, 2007; Gill et al., 2011). (Shen et al., 2001; Li et al., 2005; Manikandan and Sivasubramaniam, 2015). The fertigation system needs uniform water distribution and uniform fertilizer application Currently, research has proved that ferti- (Keller and Bliesner, 1990; Burt et al., 1997; irrigation-injection of dissolved fertilizer in Clemmens and Solomon, 1997; Pitts, 2001; water into micro and micro-irrigation systems Zerihun et al., 2003; Heerman and Solomon, has effective and economic outcomes (Fares 2007; Martin et al., 2007; Zerihun et al., and Alva. 2000; Shock et al., 2003;Alva et al., 2017). 2005; Fares et al., 2009). Fertigation requires proper and secure connection of the system The fertilizer should be soluble and components, including the source of water, compatible to be dissolved easily in water and fertilizer tank, venturi injector, and irrigation easy transferred to the whole system of system. (Strickland, 1894;Hodgson and Lake, irrigation (Koths et al., 1976; Dumroese et 1954). al., 2005; Landis and Dumroese, 2006). Water from the irrigation sources through the These the reviewed paper shows that many pipes under high pressure is converted into a types of research deal with venturi injector high-velocity at the throat of the convergent- with micro-irrigation (drip) system which is divergent portion which generates a low totally low-pressure system and low pressure (Power, 1993). The presented low fertigation rate according to the needs. pressure draws the liquid fertilizer from the tank through the suction pipe into the Also, some of it deals directly with macro convergent-divergent portion (throat portion) (sprinkler) irrigation with low-pressure where it mixes with the water (Jin, et al., specification for a small portion of the field. 2006). The outcomes will help further research to focus on the improved venturi injector In essence, the upstream pressure of the inlet parameters for efficient fertigation. water from the sources through a convergent nozzle converted to kinetic energy in the form There is a need of maintains the optimum of velocity head at the throat a portion of the effective rate of fertigation and recovering convergent-divergent nozzle (Modi and pressure to reach the required performance of Seth,2013; Rajputh,2013). As the mixed water fertigation to different types of micro(drip) and fertilizer then the fluid expands in the and macro (sprinkler) advanced technologies divergent portion (diffuser), now the kinetic in the irrigation system. energy changed or converted back to 48 Int.J.Curr.Microbiol.App.Sci (2020) 9(1): 46-61 downstream pressure energy as an outlet the Often convergent part or the constriction pressure at a convergent portion towards the section reduces its
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