Water waste is commonly deemed an undesirable, but inevitable by-product of mining processes. Yet trendy pump sealing technology exists which might nearly get rid of this waste whereas conserving power, bettering pump reliability and attaining long term operational financial savings.
Water is certainly one of the most significant, and more and more imperilled, assets on earth. That เกจวัดความดันน้ำ is understood and acknowledged by industries across the globe.
However, it is also one of the unnecessarily squandered sources in mining operations. And while the business has begun to embrace effectivity and sustainability-led advances similar to automation and renewable energy, it remains steadfastly set in its methods in relation to slurry pump know-how.
Three approaches are routinely specified by pump manufacturers to seal slurry pumps: mechanical packing, expellers (also often identified as ‘dynamic’ seals’) and single mechanical seals. All include significant limitations, including poor reliability, reduced mean times between failure (MTBF), intensive upkeep necessities and higher operational prices.
These factors alone should give mine managers trigger for a re-evaluation of the sealing methods used on slurry pumps. However, any firm with a dedication to the International Standards Organisation ISO-14001 Standard for environmental management systems and ISO-50001 Standard for energy management methods should take observe of the extreme water waste and excessive energy consumption that results from choosing these conventional sealing methods.
Inefficient sealing When used to seal the method pumps in a mine’s scrubber and floatation circuits, gland packing, single mechanical seals and expeller seals all demand one of the wasteful features of slurry processing which is seal flush water injection.
On gland packed pumps it’s important that packing is flushed with clean water to maintain it cool and lubricated, while each single slurry seals and expellers require a supply of cool, clear flush water to be injected into the method at high strain, maintaining a stable fluid movie between the fragile seal faces to maintain them cool and lubricated, whereas forcing the damaging slurry away.
The flush water required in all three sealing approaches is equipped from an external supply and injected into the method at the next strain than the stuffing box stress, consistent with the trade standard American Petroleum Institute (API) Piping Plan 32. Water which doesn’t leak onto the ground or into the process is sent to the tailings dam. This additionally has an impact on the water balance of the plant.
This approach constitutes a loss of clean water amounting to billions of gallons a 12 months globally. One large, typical slurry pump usually consumes 10 US gallons (37.8 litres) per minute, amounting to five.2 million US gallons (19.6 million litres) of water every year – a stunning statistic by any measure.
At a time when global water provide is predicted to fall short of demand by some 40% by 20301 , removing pointless use of this priceless useful resource should arguably be a central plank of any responsible sustainability programme. Yet extreme water use, and the higher vitality consumption it entails, stay embedded within the processes of many mining firms. Worse still, it’s truthful to say that it’s usually accepted as simply ‘par for the course’ by reliability engineers and administration alike.
But the fact is that water waste on any scale is a totally unnecessary feature of slurry operations as it can be virtually totally eradicated simply by employing advanced double mechanical seals and modern water administration support systems.
Improve reliability The sort of seal selected, the setting during which it operates, and crucially, the tank help system which supplies the water to maximise seal life, mix to provide the solution to extreme water waste and power use.
Modern double mechanical seals have two sets of faces, one sealing to the process fluid and one to environment, with a barrier area between the 2. They are designed to meet the arduous requirements of heavy obligation slurry applications, with fortified metallic parts which are extremely immune to corrosion and erosion. Large ports and elevated radial clearances imply the lubrication which is important to optimising seal life is maintained constantly and persistently.
A pressurised barrier tank system is central to the environmental sustainability of this resolution. It employs a thermosiphon process which provides clean, cool water to the barrier area between the double seals at a strain greater than the product stress, guaranteeing a constant, stable and clean fluid film to keep the seal faces cool and lubricated.
As the mechanical seals generate heat, the hot water in the barrier house rises to the tank and is radiated to the ambiance, allowing the cooler, denser water to sink again down to offer cool lubrication to the seal faces. Most importantly, the flush water is continually recycled, flowing across the seal faces in a steady loop and lowering leakage to absolutely the minimum, roughly a teaspoonful a day.
While API Plan 32 is unsuitable for servicing a quantity of slurry pumps in a ‘series train’ without the necessity to set up special pump techniques, pressurised barrier tanks offer rankings as a lot as 435 psi (30 bar), making them ideal for these applications. Self-topping and self-pressurising, they are also virtually maintenance-free.
Where no plant water supply is on the market for topping up the tank techniques, or the supply has inadequate pressure, fluid delivery items can be chosen to supply the barrier fluid to seal faces. These have the added advantages of having the power to supply a water/glycol mixture or oil to provide freeze safety in extraordinarily chilly climates.
Wide-ranging benefits The advantages of upgrading to fashionable sealing solutions and assist systems had been felt by a coal mine in Poland utilizing a slurry pump to provide coal mud at 9 bar (135 psi) to filter press. Flushed packing resulted in huge dilution of product, leading to greatly increased filtration instances and costs. The pump was sealed with a double mechanical seal designed to fulfill the arduous necessities of the process.
The supporting seal tank system decreased leakage and product dilution to virtually zero. Return on investment was swift and the financial savings long-term. The benefits by means of water conservation have been equally longlasting and the company’s popularity enhanced.
The mining business should take care of a tough and expensive problem in terms of sustaining rotating equipment. But the planning, processing and disposal of flush water constitutes an operational and financial burden which is entirely avoidable.
And when an organization can remove water waste concurrently rising reliability and lowering long run operational costs, the choice to upgrade to fashionable methods should certainly be a moral imperative in addition to making sound business sense.