Ro desalination system for irrigation purposes : [electronic resource]. II. A case study /

Year book of Misr Society of Agricultural Engineering : The 20 th. Annual Conference of the Misr Society of Agricultural Engineering "Agricultural Engineering and Country Challenges"

Includes references.

The continuous use of brackish groundwater in irrigation in desert
regions lead to soil salinization and thus degradation to the extent that it
makes it difficult to cultivate without reclamation by leaching. Therefore,
this research introduces the lise of reverse osmosis 'RO' desalination of
brackish groundwater utilizing renewable energy for irrigation purposes
in the desert farming of Wadi El-Natnm, Egypt as a case study. RO
laboratory experiments were conducted on a reverse osmosis desalination
unit at the thermal engineering lab in the Faculty of Engineering,
Alexandria University to determine the performance of the reverse
osmosis unit. The field experimental design consisted of completely
randomized blocks with three replications and six levels of irrigation
water salinity to evaluate the effects of using brackish groundwater at
different salinity levels on onion yield, water use efficiency, and profit of
onion yield. All plots were drip irrigated with water from a well having
an ECi of 3000 ppm (4.7dS/m) mixed with the desalinated brackish
groundwater to obtain the required six levels ofsalinity (500. 1000, 1500.
2000, 2500 and 3000 ppm). The yield and profit of onion were found
highestinthetreatment of500ppmwatersalinity. Thelowestwasfound
in 3000 ppm treatment. lfrigation with RO would enable a 56% and 73%
increase in crop yield and profit of onion yield over the yield and profit
obtained with current management practices. The current irrigation
practice with brackish groundwater (3000 ppm) has increased the initial
soil salinity in the root zone from 20 dSlm to 28 dS/m by the end of
growing season (+35%). However, irrigation with desalinated water (500
ppm) has decreased the initial soil salinity in the root zone from 20 dSlm
to 17 dSlm by the end of growing season (-15%).

Summary in Arabic