Processing, December 2020

pumps Those industries include water and wastewater pulp and paper mining chemical processing and others Digitalization example for pressure filtration Another example of digitalization is adding monitoring to industrial pressure filtration units The aforementioned steel mill for example has more than 10 pressure filters in its plant These filtration units are typically semi automatic or fully automatic machines They are also somewhat complicated and many have significant levels of automation or digitalization Some are manned and require assistance for cake release and others are more automated In the mining industry a digitalized cloud based monitoring system was developed for a zinc mining operation This mine had three automatic vertical pressure filters and it was struggling to meet production with these machines The mine was starting to investigate purchasing another 1 million filter and mine operators were under the assumption that these three machines were facing an 85 to 90 utilization rate As an alternative to purchasing a new filter the mine was offered a digitalization package to monitor machine performance The cost was fractional compared to investing in another filtration unit and after a few months the digitalization package began to capture valuable data The complete filter plant had been controlled by a traditional DCS system However the DCS did as it was programmed and operated on normal logic What it was not detecting was that these filters were waiting for multiple hours per day Two of the filters were even waiting up to four total hours per day Digitalization monitoring detected that the culprits were the compressed air system being recharged the pressing water station and wash water station being recharged and waiting for the slurry tank to be refilled The mine now has more than enough pressure filtration capacity to meet their current filtration needs The mine focused on fixing these delay issues and the current result is that they can run two filters while the third is on standby By fixing these issues the mine if it were able to keep the slurry tank filled could produce 58 million more pounds per year If the mine accomplished this with a 25 yield from production their revenues could increase by more than 18 million 24 Processing DECEMBER 2020 Figure 3 In the bottom right illustration the circle on the graph plots where the two pumps are running The two green lines signify the range that would be considered acceptable for the BEP The orange line would be the exact spot for the BEP The other graphs are the manufacturers pump curves Running these pumps so far below their BEP creates a situation where the pumps are constantly stressed Thus they are wearing their pumps out or doing damage to the pumps at a faster rate Alarms were sent to personnel by email to turn off one of the pumps Then the running pump went right within the BEP zone and the other pump was completely off Figure 4 Shown above are two pumps running during the summer months when temperatures are higher and more water is used Both pumps are within the BEP range and thus are not experiencing unnecessary wear and destruction