Service Contract No 2007 / 147-446 - Swaziland

More documents

Recommendations

Info

The effects of different nozzles/emitters and different sprinkler packages observed in thisproject were evaluated using the table below. Different emitters respond differently to thesame amount of pressure and table 6 below indicates the properties of the different sprinklerpackages found on site.Table 6.Technical properties of sprinklers found on site at 35m operating pressureSprinkler Package <strong>No</strong>zzle size Discharge (m3/hr) Wetted Radius (m)VYRSA 70 11/64’’ 1.36 15.9Rain bird 14070 11/64’’ 1.39 15.2Rain bird BH30 11/64’’ 1.38 14.8RC 140 11/64’’ 1.36 15.9Four sprinkler packages and one nozzle sizes was identified in both phases as shown in table6 above. Flow variation due to the different sprinkler – nozzle combinations is 2.18% forphase one and 0% for phase two. Emitter variation, therefore does not affect discharge anddistribution uniformities of this system, except for the wetted radiuses. The averageapplication rate of the above combination is 1.36m3/hr and is acceptable according tosugarcane norms. This different combination has an effect also on the wetting diameter dueto their different body trajectory angles.Gross application rate (GAR)The gross application rate (GAR) of the sprinkler was thereafter calculated, by means of thefollowing formula;GAR qe1000A ....…………………………………. (11) mm/hWhere; GAR = Gross Application RateA = wetted area (m 2 )The GAR is a fraction of emitter discharge and sprinkler spacing as indicated by equation 11above. The average GAR for Maphobeni phase one irrigation is 4.2mm/hr and 3.9mm/hr forphase two. The recommended GAR is 4.2mm/hr and this means that Maphobeni FA isslightly under-irrigating phase two. However, when flow measurements readings from Block Iare excluded the GAR of phase two increases to 4.2mm/hr.Maphobeni Farmers Association Report - 2009 Page - 45 -
6 A S S E S S M E N T O F O P E R A T I O N , M A N A G E M E N TA N D M A I N T E N A N C E O F T H E I R R I G A T I O NS Y S T E M6 . 1 O p e r a t i o nOperation and maintenance manual not availableThe different components forming the irrigation system require different operating proceduresand these are obtained from an operation and maintenance manual. This document is notavailable and for efficient performance of these components, it must be compiled. Theconsequence of not having this document is seen during this evaluation in that incorrectsequences are followed in opening and closing the pump. Also, this document helps in theformulation of a maintenance plan and provides guidelines to be followed duringmaintenance.Financial viability for smallholder growerThe late conclusion of loan agreements (seasonal loans) results in the late delivery of inputsand late application of fertilizers and chemicals, which reduces yields and sucrose content,resulting in reduced financial returns per hectare and inability to recoup invested capital. Inaddition, the absence of any dividends for distribution to farming association members at theend of each season can lead to a decline in the cohesion of farmers’ associations/cooperatives,a cohesion which is essential to increasing on-farm efficiency.Figure 22. Tonnes Cane per HectaresYield data for the first three seasons could not be obtained but for the above graphproductivity has been on the increase since 2004.Maphobeni Farmers Association Report - 2009 Page - 46 -
Page 1 and 2:
Restructuring and DiversificationMa
Page 3 and 4: DISCLAIMERThe contents of this repo
Page 5 and 6: 5.2 Delivery tests ................
Page 8 and 9: LIST OF APPENDICESAppendix 1: SEB u
Page 10 and 11: 1 I N T R O D U C T I O NAssociatio
Page 12 and 13: pumps. 2 x Howden 100-400 in the ri
Page 14 and 15: 3.1.2 R e v i e w o f C o n t a c t
Page 16 and 17: 9 SCHEDULE OF BLOCKS THAT IRRIGATE
Page 18 and 19: Maphobeni Farmers Association Repor
Page 24 and 25: Based on equation 1 above the flow
Page 26 and 27: ReducersThe inlet on the pump sucti
Page 28 and 29: d1.5d0.5dd3d 3d 1.5dFigure 9. Spaci
Page 30 and 31: hf6375kQ4d2……………………
Page 32 and 33: Table 1. Pump and motor specificati
Page 34 and 35: Table 2. Irrigation pumps evaluatio
Page 36 and 37: Phase two river pump station‣ Pum
Page 38 and 39: Filters: 3%Capital Recovery Rate (C
Page 40 and 41: 4.3.1 M a i n l i n e s i z eThe So
Page 42 and 43: 5 F I E L D E V A L U A T I O N O F
Page 44 and 45: 5.1.2 S p r i n k l e r p r e s s u
Page 46 and 47: 0 L/4 L/2 3L/4 LL3L/4LL/2Test block
Page 48 and 49: Phase two booster Pumps running und
Page 50 and 51: The installation of this unit (on t
Page 52 and 53: Old AgePhase one of the irrigation
Page 56 and 57: Interest RatesIt can be argued that
Page 58 and 59: 6 . 2 M a n a g e m e n t P r a c t
Page 60 and 61: 6 . 3 M a i n t e n a n c e S u r v
Page 62 and 63: 7 C O N S T R A I N T S T O E F F I
Page 64 and 65: phase one and two was found to be 1
Page 66 and 67: 8 R E C O M M E N D A T I O N STo e
Page 68 and 69: OVERALL MANAGEMENT AND MAINTENANCEM
Page 70 and 71: 10 L I T E R A T U R E R E F E R E
Page 72 and 73: 11 P R O D U C T I N F O R M A T I
Page 86 and 87: SEB usage for River pump station Ph
Page 88: Appendix 2: capital recovery factor
show all

Service Contract No 2007 / 147-446 - Swaziland

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?