The treatment of quarry
effluent with C. zizanioides resulted
in the following observations: pH slightly reduced in day 2, day 4 and day 6 (3
%, 36 % and 44 % respectively). There was a continuous reduction in BOD from
day 2 to 6, while COD was reduced by 53 % in day 2 (Figure 3), but relatively
stable in day 4 and 6. Pb was slowly reduced (13 %) in day 2, but faster in day
4 and 6 at 79 and 96 % respectively. Zn, Fe, Co and As were reduced below
detection in day 6.
Read: 5 Tech Trends To Watch In 2017
When C. nigritanus was used in treating the
same water sample, the following observations were made: pH slightly reduced by
7 % in day 2, 34 % in day 4 and remained at 35 % in day 6. BOD was reduced in day 2 (50 %), but
relatively stable in day 4 (53 %) and 6 (56 %). COD was also reduced by 50 % in
day 2 but slightly changed by 55 % and 56 % in day 4 and 6 respectively. Pb was
slowly but continuously reduced from day 2 to day 6. While, Zn, Co and Mn were
reduced below detection in day 6 (Figure 4).
T-cal values obtained from these parameters when
treated with C. zizanioides and C. nigritanus are as follows: pH (0.621),
BOD (1.181), COD (-0.250), NO3- (-0.18), PO43-
(-0.774), Pb (-0.649), Zn (-1.00), Fe (2.226), Co (-1.000), Mn (0.076), As
(0.855) (Table 5).
Effect of Vetiver on Urban Irrigation Water
When irrigation water used in urban Agriculture was treated with C. zizanioides, the following changes were observed: Slight change in pH from day 2 (24 %) to day 6 (37 %). Continuous reduction in BOD and COD from day 2 to day 6 with an average change of 66 and 64 % respectively. Co was only slightly changed in day 2 (14 %), but underwent rapid change in day 4 (Figure 5). Fe, Co and Mn were below detectable limits in day 6.
Read: 5 Tech Trends To Watch In 2017
Read: 5 Tech Trends To Watch In 2017
Similarly, treating urban irrigation water with C. nigritanus resulted in the following observations: pH remained unchanged in day 2, but slightly changed in day 4 (21 %) and day 6 (30 %). There was a continuous decrease in BOD and COD from day 2 to day 6 at an average of 65 % and 68 % respectively. Continuous decrease in Co from day 2 (57 %) to day 6 (100 %) was also observed. Co, Mn and As were below detectable limits in day 6 (Figure 6).
T-cal values obtained from these parameters are as follows: pH (1.450), BOD (0.555), COD (-1.222), NO3- (1.257), PO43- (-0.487), CN- (0.709), Zn (1.890), Fe (0.443), Co (-1.000), Mn (0.996), As (-1.964) (Table 5).
No comments:
Post a Comment