A Key Question Managers Are Faced with Is:
Is it better to purchase smaller, more manageable quantities of a fluid at higher prices which then can be poured directly out of a 1-gallon or a 5-gallon container? Or, should you purchase larger quantities and then have to deal with transferring the fluids out of the container safely? In addition, OSHA and EPA have increased environmental health and safety (EHS) regulations, which makes decision making critical. If there is a chemical spill, the paperwork for the EPA report, if required, can be very time consuming.
The cost of lost liquid inventory and clean-up time can be an expensive proposition. The majority of spill problems involve transferring liquid from a 55-gallon drum. A large number of companies rely on workers to manually lift and tip the drum and pour the fluids into a smaller container, or use a fork lift for lifting and tipping the contents directly into another container. In either case, spills can easily occur. These methods require having spill kits with related mats, pigs, berms and related equipment on hand. Overflow is almost impossible to avoid. If the drum has a faucet, it must be manually lifted to assure it is completely drained. If the faucet is clogged, it must be removed and the contents emptied which may cause additional spills. Incomplete drainage of the faucet may end up with the disposal of costly inventory. All of these manual solutions to the problem of removing liquids from drums frequently result in spills that present management with OSHA safety issues or EPA hazard issues. Management is never happy with the loss of costly, usable fluids, particularly when a low-cost, preventive approach exists. The popular saying that “An ounce of prevention is worth a pound of cure,” makes a lot of sense. That “ounce of prevention” can be found with the use of inexpensive pumps, instead of human strength, in conjunction with mechanical lifting equipment. However, the pumps must be able to handle the great variety of corrosive fluids that are being supplied in 55-gallon drums, and do it without corroding or contaminating liquids, especially liquids of high purity. In addition, electrically operated pumps present an unnecessary fire danger that must be considered. The pumps selected for transferring these fluids from drums to other containers or directly into application equipment must be low in initial cost, easy to repair and maintain, readily available and simple to use. The following pump types are the major non-electric, nonmetallic drum-emptying devices that are currently being used in industry today. Here’s how they compare in performance:
These pumps operate from the top of the drum. They include a discharge hose that runs down the side and enters into the smaller container. They use an internal plunger that must be pulled up and pushed down to create the suction needed to create and maintain the flow. The fluid flow is erratic and unsteady, emerging with a pulsing, spitting action that can prove a safety hazard. The transfer output with a 2” bung adapter can be up to 22 ounces per stroke and the volume depends on the strength and repetitive action of the employee.
Similar in action to Pull-action pumps, these units require a simple up and down action created merely by pushing on the top of the pump. They come with a siphon tube long enough to reach the bottom of the drum. They generally deliver up to 8 ounces per stroke, which makes transferring large quantities very time consuming.
This type of pump is threaded into the top of a drum. They are activated by a crank handle, which as it turns it builds up the suction and starts the flow. It requires constant cranking to maintain the flow and accurate timing is necessary to avoid spillage when stopping the flow. This is very critical when filling a small container. These pumps offer a transfer rate of 5-20 gallons per minute.
This pump design is mounted on the top of the drum and is held in place with an airtight rubber compression fitting. Pressure is added by simply pumping the piston several times. This automatically prepares the fluid to flow. Opening the spring-loaded tap starts the flow and closing the tap stops it. Pressure needs to be added from time to time to keep it flowing. Fluids are dispensed in a smooth, continuous stream at rates to 4.5 gallons per minute. An internal safety design relieves pressure if the vessel reaches 7psi. These pumps are available with various types of rubber components (Viton®, EPDM, nitrile, etc.) depending on the chemical being dispensed to give them compatibility with over 850 liquids and solvents. The four nonmetallic pumps described above make it clear that when it comes to solving the problems of handling the environmental and workplace problems created by liquid spills, prevention beats clean-up by a wide margin.
Article courtesy of Goatthroat