A bulk solids handling system by Flexicon, has vastly improved the transfer of bulk resin in the production of an aqueous soap solution for speciality chemicals company ArrMaz Custom Chemicals. The system is helping the company achieve accurate batch weights without investing in an automated batch weigh system.
ArrMaz Custom Chemicals produces speciality chemicals for the mining, water treatment, fertiliser, asphalt and construction industries. Since it began in 1967 as a phosphate producer, it has introduced numerous products and expanded its markets into 70 countries.
In addition to extensive quality control and customer service programs, the company has implemented a ‘Total Safety Culture’ to protect its employees and the subtropical ecosystem of central Florida. ArrMaz goes beyond environmental regulations in operating the majority of its open air manufacturing facility under a roof to provide safe working conditions while minimising storm water run-off.
One ArrMaz product is a resin soap called Arr-Muls, used as an emulsifier in slow-setting asphalt and as an air-entrainment agent in masonry cements. The process uses heat and agitation to dissolve a solid resin into sodium hydroxide or potassium hydroxide to produce an aqueous soap solution. To transfer the solid resin from sacks in kgs, ArrMazz originally installed a Flexicon, manual bag dump system comprising a hopper with a dust collector, and a 6.7m flexible screw conveyor to discharge the resin into a 22,700L tank. Each 9,090kg batch of resin, represented 400 sacks that required lifting, slitting and dumping by the operator.
ArrMaz then decided to retro-fit a low-cost bulk bag unloader to the bag station and so minimise the manual handling. This helped prevent potential injury and other health hazards associated with the handling and disposal of bags and minimised waste.
The Flexicon flexible screw conveyor was retained since it is not only well suited for use with a bulk bag discharging station but also has handled the resin effectively despite the material’s tendency to interlock and degrade. The existing dust collection exhaust system was also retained but moved from above to beside the hopper to allow positioning of bulk bag spouts directly above the hopper.
The new hardware consists of a four-post unloading frame, at the top of which is a cradle with wide receiving cups supporting a removable bulk bag lifting frame that is lifted and positioned using a forklift truck, allowing operators to connect full bags and disconnect empty bags at floor level.
A conventional iris valve above the existing manual dumping hood prevents material flow from the bulk bag until the bag tie has been untied.
It then allows controlled discharge of the bulk resin into the hopper which feeds the flexible screw conveyor.
The frame is also equipped with spring-loaded ‘Pop-Top’ bag extension devices that raise the bag-lifting frame and elongate the bag as it loses weight, promoting flow of material from the corners of the bag through the spout.
Simultaneously, pneumatically actuated Flow Flexer plates raise and lower opposite bottom sides of the bag into a ‘V’ shape at timed intervals, loosening agglomerated material and directing it through the bag spout.
With the new system in place, ArrMazz Custom Chemicals began sourcing 99 per cent of its resin in 1,000kg bulk bags, which are discharged in their entirety and supplemented with manually dumped 22.7 kg sacks to achieve target batch weights of 9,090 kg.
The bulk bag unloading capability has cut resin loading time from about 60 minutes down to 15 and by retaining the original bag dump station system, accurate batch weights are achieved without investing in an automated weigh batching system.
