Page 1
Page 2
Page 3
Page 4
Page 5
Page 6
Page 7
Page 8
Page 9
Page 10
Page 11
Page 12
Page 13
Page 14
Page 15
Page 16
Page 17
Page 18
Page 19
Page 20
Page 21
Page 22
Page 23
Page 24
Page 25
Page 26
Page 27
Page 28
Page 29
Page 30
Page 31
Page 32
Page 33
Page 34
Page 35
Page 36
Page 37
Page 38
Page 39
Page 40
Page 41
Page 42
Page 43
Page 44
Page 45
Page 46
Page 47
Page 48
Page 49
Page 50
Page 51
Page 52
Page 53
Page 54
Page 55
Page 56
Page 57
Page 58
Page 59
Page 60
Page 61
Page 62
Page 63
Page 64
Page 65
Page 66
Page 67
Page 68
Page 69
Page 70
Page 71
Page 72
Page 73
Page 74
Page 75
Page 76
Page 77
Page 78
Page 79
Page 80
Page 81
Page 82
Page 83
Page 84
Page 85
Page 86
Page 87
Page 88
Page 89
Page 90
Page 91
Page 92
Page 93
Page 94
Page 95
Page 96
Page 97
Page 98
Page 99
Page 100
WORLD PULPPAPER 69 Problem solving involves a good understanding of the various causes of odours and the testing methods that are required to identify the type of odour and its source the neat form as this can produce toxic gases. Both products are mixed with water in the system to safely produce the desired active. The feed system has a solid partition in the middle. The Oxaminer and hypochlorite are separated by this partition. If there is a leak in the system the two neat products cannot get into contact with each other. The feed system is designed with safety first in mind. The system includes Pre-rinse and post-rinse cycles Alarms that trigger wash sequence and shutdown Lowhighno chemical flows Low or no dilution water flow Loss of air pressure Loss of power Emergency rinse in case of power failure Leak-proof casing with integrated spill sensors Back-up water source for emergency flushing Thus if there is any interruption in operation the system will automatically shut down and flush. Figure 1 is a diagram of an Oxamine feed system. Traditional chlorine products are controlled to a free chlorine measurement. In the case of Oxamine a total chlorine measurement is used. An example is an alarm in the system that will send a text to a Buckman associate or to mill personnel informing them of the alarm. Case Study 1 A 100 recycled packaging mill was receiving complaints from neighbours about odour coming from their effluent plant. The odour included VFAs. An Oxamine program was started and there has been a marked reduction in complaints over the period of one year. Case Study 2 A 100 recycled packaging mill needed to be below a target VFA level in some of their board grades. An Oxamine program was started that treated both the pulp and the water system. ATP measurement showed a tenfold decrease in total microbial population and final product testing confirmed that the VFA levels were well below target. Case Study 3 A mill needed to reduce the VFA levels in their final product. An Oxamine program was started and there was an almost immediate reduction in VFAs. Chart 1 shows the results. Another benefit of this program was that odour in the mill was reduced. CONCLUSION Odour problems in pulp and paper take many forms. Volatile fatty acids are becoming more of an issue in recycled packaging operations. The two main reasons for this include the use of recycled paper with its contamination and the closing up of water systems. Both of these result in higher microbial populations. Problem solving involves a good understanding of the various causes of odours and the testing methods that are required to identify the type of odour and its source. In the past various organic and inorganic type microbicides were used to control VFAs they could be expensive and not always effective. The introduction of Oxamine by Buckman has given the recycled packaging operation a tool that can effectively control VFA levels whether it is an odour issue or a final product requirement. Buckman has safe well designed feed systems to ensure the correct and safe application of Oxamine. Oxamine has proven effective in controlling a wide range of microbial issues including VFA control in a number of recycled packaging mills.Chart 1. Case study 3 VFA levels