Printer Friendly

A Sector in Search of Answers: The latest slurry handling solutions indicate the core needs of miners facing uncertainty.

These hard times in the coal sector may someday prove to have had an upside, according to some insiders in the slurry handling solutions space. For example, better days and markets may have had the dubious side effect of validating inefficient processes and technologies at mines. "The mining sector already tended to be old school," Trey Walters, the founder of a company that makes software that models fluid system dynamics. "It is also the case in developing countries where the engineers have lower labor costs and sometimes less budget to procure the latest technologies."

Ben Ornstein, a strategist at a slurry density meter maker, agreed. "If we look at instrumentation as a whole in the coal industry, historically, what we accept from that instrumentation is something we would not accept in our day-to-day life," he said. The decline in coal prices and demand has forced companies that otherwise wouldn't ask some key questions, he said. "How do we make our processes more efficient? What new technology can we implement to make our end result better? All of these things are kind of where we are at now." Such questions prompted the latest round of innovations, which are pitched as speaking to the core needs of a miner facing uncertainty. A few examples reveal both the ingenuity of suppliers as well as the topmost concerns of miners and plant managers today.

Totalizing the Targets

With the announcement of the latest round of updates, Red Meters' V2, featuring an onboard computer, has transcended the confines of the non-nuclear slurry-density meter space, the company reported.

"What we've tried to do is put a full solution in a device," Ben Ornstein, head of strategic planning, Red Meters, said. "It went from a density meter sensor to really a process-monitoring and characterization device. This product now functions as a control system for a client that doesn't have the money to spend on a new or upgraded DCS or SCADA."

Launched in 2019, the V2 is advertised as capable of continuously measuring "the process characteristics of any wet or dry continuously flowing media, while producing a unique process signature." The company reported that via the Red Meter "critical information is provided, so a user can receive SPC measurements and process capability, as well as providing the data to diagnose process faults, leakage, flocculation, clogs, and process blowbacks, to name a few."

With the latest updates, V2 "electronics boast HART Protocol, which acts as a bridge between old and new technologies, as well as Modbus," Red Meters reported. "V2 electronics support HART output out of the box for any of the variables being measured, not just density or percent solids." Further, the V2 "can be used as a Modbus slave."

Software updates allow for remote support and diagnostics, and enable customers to request remote assistance.

These features scratch the surface of the value the V2 brings to a plant or process, Ornstein said. "Some of the things that we have implemented recently such as an expanse of different communication protocols, cloud computing techniques and connectivity things, these are all looking towards the future of industrial process control," he said. "Our device is an IoT design device."

The onboard computer "allows users to receive the many direct measurements that we take," Ornstein said. Included are slurry weight, temperature and pressure measurements, made roughly 3,000 times per second.

The computer leverages "a series of algorithms" to "assess the different sensors and put them into the appropriate format and analyze them to equate an end result, whether that is density or specific gravity or percent solids," Ornstein said.

"We take all of these different direct measurements and then we allow the client to customize the analysis that happens inside our unit," he said.

The resulting multipower, multipoint datasets can then be output to a DCS or SCADA system.

Thus, the V2 "allows for this real-time statistical process control at a localized source as opposed to having to do that work in the SCADA or DCS," Ornstein said. "The processing power that you have in the SCADA or DCS system can be used to do other things."

While the meter functions offline, an internet connection unlocks critical capabilities and benefits.

For example, an internet connection enables "setting alarms so that you know that your process is in control and that you can know the instant it goes out of control or if there is a trend of it going out of control," Ornstein said. "The internet connection allows you to send it to third-party sources, such as an email account or a cell phone."

The internet connection also enables the customer to push data from the meter to a database hosted by Red Meters. "It allows for cloud storage of data if that is something that you would like," Ornstein said.

Perhaps more importantly, the internet connection allows a user to contact Red Meters for assistance in installation, calibration, programming and support. "Remote support is the newest offering by Red Meters that we are really excited about," Ornstein said. "Downtime is something we don't want our clients to have because of the Red Meter at all."

He described mechanical installation of the meter as "simple," but where the "intricacies of what we do comes in is in the electronics." With access and approval from the customer, Red Meters can remotely address issues with the computer and assist with calibration "on the client's schedule," Ornstein said. "When the client is ready, that is when we go to work."

The evolution of the V2, steered by "hundreds of whiteboard sessions," centered on an effort to simplify installation and support, Ornstein said. "The early-stage thought was how could we get into the unit to do the startup and to do the troubleshooting, because it will take our guy 20 minutes and they'll be much happier and it will be easier for us," he said. "And then the question arose of what else can we do with this? What other avenues and doors does connectivity offer? What else can we provide for our clients with that connectivity?"

One answer was upgrading the computer to take live outputs and historical readings and "totalize the targets," the company reported.

"When we were selling a density meter, we were just establishing density based off of a volumetric measurement and a weight measurement and just using the other ancillary information internally in our system," Ornstein said. "The reality is that those are also useful datasets for our clients and our perspective clients," he said. "What if we can provide all of these things?"

With the release of the updates that provide exactly that, the question becomes how to market a groundbreaking solution in a space commonly viewed with some skepticism. "Our clients used to say density meters are snake oil. They all claim to work. They don't work," he said. "Well, we work. We can prove it categorically."

Adopting the V2 could be seen as the same bold step as adopting any other new IoT or Industry 4.0 solution, he said, but it shouldn't be. "The initial investment seems high. But it is actually not," Ornstein said. "The return on investment on these new systems, and not just the V2, and what they can provide in terms of understanding, in terms of datasets, in terms of making your process more efficient, removing human error, and having irrefutable data to determine if processes were followed or not followed, is beyond valuation. And it is the main thrust of the new age of technology that we are in."

21st Century Modelling

AFT Fathom 10, software for fluid system modelling, can help miners cut costs, improve safety and otherwise evolve in an increasingly demanding economic environment, Applied Flow Technology (AFT) reported.

"Pumps, fans and compressors in your facilities are usually the biggest energy users," Trey Walters, president and founder, AFT, said. "In some facilities, we're talking more than 50%. Most are oversized and inefficiently use energy," he said. "AFT Fathom system models can help pinpoint opportunities to reduce energy usage."

The software is pitched as capable of accurately simulating individual system components, integrating equipment data, and providing an array of features.

Among those features is the capability to experiment, change input data, import layouts and dimensional data, export to Excel, specify alerts, enable cataloging of components, and assess viscosity and frictional changes associated with pumping non-settling slurries, the company reported.

Foremost among the benefits implied is accuracy well beyond what historically is obtained using strictly Excel. "Here we are two decades into the 21st century and there are still a surprising number of engineers using spreadsheets," Walters said. "Spreadsheets will always be used in engineering, but as systems get more complicated it is all too easy for something to be overlooked or oversimplified in a spreadsheet. AFT Fathom allows engineers to look at many more potential operational situations in a short time before committing to hardware, thereby ensuring their designs will be safer and more economical."

All without significant additional effort. "Engineers can enter data on their solid particles, density and size distribution, and AFT Fathom can predict the piping pressure drop as well as the pump derating," Walters said.

Ease of use is a benefit that should speak to many engineers, he said. "Engineers are always busy and have too much on their plates, and if we can help them leverage other existing data within their company to save them time on their fluid systems, they should consider it," Walters said. Further, "I would ask whether the current tools they use have evolved to meet changing requirements they encounter regarding safety, responsible energy use, and being able to exchange data with other tools their company uses like pipe stress, CAD and even Excel."

Fathom 1.0 hit the market in 1994 as a graphical drag-and-drop modelling tool. At the time, such solutions did not exist, making the release "a major milestone for the global engineering community as it meant engineers could start moving from text-based tools like Excel and in-house software to using visual tools like AFT Fathom," Walters said.

Which speaks to another of the benefits offered. "All AFT software is desktop-based," Walters said. "Our customers have largely told us they want to keep our software and their models, which are sometimes proprietary, and sometimes have national export control issues, behind their firewall."

Walters said the ideal customers are owners "who may have struggled with operational problems in their pumping systems, a history of safety issues, high pump repair costs, or have mandates to reduce their energy use," he said. "In the end it is the engineering design firms who are our biggest customers."

One such example is a mine in Indonesia that had a dewatering system in need of reconfiguration due to operational changes. "Maintaining an adequate [Net Pump Suction Head Available (NPSHA)] across multiple, distributed pumping stations was critical to successful operations," Walters said. "An engineering firm in Australia modeled this in AFT Fathom and was able to demonstrate five years of successful operations."

Fathom requires only a laptop running Windows. "Pretty standard stuff," Walters said.

The company offers updates and technical support from partners in 35 countries. "When customers lack time or expertise, we offer consulting services to assist them," Walters said. "And we teach regular training classes in our office in the USA and around the world," he said. "I myself have personally taught on-site training classes to engineers in the mining sector in the U.S., Canada, Peru, South Africa and Australia."

That the software is developing inroads to the coal mining and processing space is a sign of the times, Walters said. "Currently, the sector has many economic pressures due to environmental and health concerns. Miners have to evolve in order to simply exist."

Facilitating that is a part of AFT's mission, he said. "AFT is a company that is passionate about helping engineers around the world design and operate fluid systems that are safer, more reliable and more cost effective."

Ensuring Durability

Flowrox showcased its peristaltic pumps and pinch valves, both of which it described as the most abrasion-resistant on the market.

The pinch valve "is really the right product for the most mining customers," said Todd Loudin, president, North American operations, Flowrox.

When it comes to valve design, there are two ways to combat abrasion, he said. "One way, if you are dealing with metal components, is to make them harder, for example with tungsten carbide or stellite," Loudin said. "The other way is to go softer. We utilize rubber. Just like rubber-lined pipe, we have a rubber sleeve inside of our valve."

When the valve closes, it chomps down on the rubber sleeve on both sides, closing the middle. "The rubber is really excellent for the abrasion," Loudin said. "The other really fantastic feature of it is, it is a relatively inexpensive part to replace when the rubber actually does fail at some point down the road."

Valves made of metal components are comparatively expensive to repair and replace, he said. "Instead of taking a metal-seated ball valve or a really expensive knife gate that has a stellite or tungsten carbide-coated ball or gate, which would have a really big price tag, ours doesn't have a big price tag," Loudin said. "You could take it and replace it very quickly and easily. It is one of the simplest valves to repair in the industry today."

The company's heavy-duty pinch valves are advertised as helping improve efficiency and productivity, helping reduce maintenance, and offering greater control. The construction materials of the sleeve, body and actuator "can be tailored to suit your process conditions," Flowrox reported.

The company's general line pinch valves are described as "extremely wear resistant," offering reduced maintenance, extended longevity, and availability in dimensions ranging from 50 mm to 250 mm, "with manual, pneumatic or electric actuator," Flowrox reported. Flowrox's most popular pinch valve is available in sizes 25 mm-1,000 mm.

Loudin said the company's peristaltic pumps stand out in that they are capable of pumping as much as 80% solids. "A centrifugal pump may be limited to, in an ideal situation, roughly 35% solids," he said. "Some of them will go up to 50% or 55% solids." At those concentrations, "the wear inside of those pumps becomes astronomical and it costs a whole lot of money."

The peristaltic pump can handle those concentrations and higher at 24/7 operations, he said.

The pump employs a rubber hose and a roller, which mashes the hose. "Basically, it pushes the liquid through the rubber sleeve," Loudin said. "It discharges out. Once the compression is off of it, the hose opens back up, sucks more slurry into the hose, and it just continues to pump all day long."

Loudin said ease of maintenance is the foremost selling point of the pumps. "Again, the main wear component is the rubber hose," he said.

Typically when a hose is breached, it starts as a pinhole. Slurry ends up inside the pump casing. "We've got a hose leak detector on every pump," Loudin said. "Once the level rises to a certain point, this level detector will pick that up and send a signal to your PLC or the VFD, saying shut the pump down," he said. "Then all they've got to do is come and remove this access cover, put a new rubber hose in, and they're back in business."

The entire process could span as little as 20 minutes and can be done by a routine maintenance crew.

Among other things, the pumps were designed to speak to a miner's need to reduce both opex and capex, Loudin said.

The pumps save electricity by as much as "40% compared to a conventional hose pump," Flowrox reported. Savings on spare parts costs could be higher.

Over time, those savings can dramatically improve the bottom line.

"There is one case down in Mexico using really big pumps by a competitor," Loudin said. The miner was on the hook for $4 million per year in replacement parts. "Whereas if they had our pumps in that same application, they would spend a quarter million dollars per year," Loudin said.

The pumps are easy to install. "The smaller pumps have stainless steel-threaded connections," Loudin said. "The bigger pumps have an ANSI 150-lb flange," he said. "Connect, then connect electricity and off you go."

On installation, the rubber hose functions as a gasket. "It is really dummy-proof," Loudin said.

And it is ideal for an application moving a slurry with a high percentage of solids, "for instance on thickener underflow," he said. "If you've got real solid slurries that you need to control or shut off, this is really a great product for those kind of situations."

Customizing Mining Hoses

Salem Republic Rubber Co. showcased the Mining Hose and the Salem FLEX Slurry Handling Hose, two long-established products.

The company described the Mining Hose as a customizable solution. "Everything that we make, we talk to the customer and ask a few questions," Jason Phillips, sales engineer, Salem Republic Rubber Co., said. "What material is going through? What is the temperature? What is your particular application? What kind of pressure? What kind of end-fittings do you want?" he said. "We ask a series of questions and then we design the hose around what they need."

Customizations include length, tube linings, wall thickness, reinforcement options, end fittings and covers.

Hoses can be up to 42 in. in diameter and up to 50 ft long. Tube lining options include different types of natural and synthetic rubber. Reinforcement options include the use of multiply synthetic fabrics or helically wound steel. Coverings can be color coded based on application or according to site or plant-safety specifications.

"We can put a l-in.-thick tube," Phillips said. "We can build in different types of end fitting and flange drillings," he said. "Maybe they want a built-in nipple, or maybe they want a rotating flange on one end. We can put gimbal hoops in there to give us more flexibility."

Phillips said the company sells the Salem Flex hose in bulk to miners interested in having it on-site for immediate use when needed. "In a pinch, if they need 10 ft or 12 ft of hose, they can cut it and install it there," he said. "These hoses are built to fit specific couplings where we can build a hose around applications and different end-constructions."

By ordering custom-built hose, the miner gets a product designed for a longer life. "Typically we try to find out how well their current hoses or pipes are lasting, what is going through them, and can we use a different material that is going to be a more abrasion resistant for their particular application," Phillips said.

The Salem FLEX Hose is for field-measured cut-and-couple ap plications, specifically for use in suction and discharge processes. Tube thickness sizes offered are 1/4 in. and 3/8 in. The hose is reinforced with spring steel wire helix and high-tensile-strength cord and is covered with corrugated black rubber. It is pressure rated for 100 lbs per in.2 Available sizes range from 2 in. to 14 in. in diameter and up to 50 ft in length. Custom lengths are available.

"Our Salem FLEX Hose is more for where the customer has these specific end fittings, and then we can sell bulk hose," Phillips said. "We are able to do more customization with our Mining Hose than with our Salem FLEX."

Both offerings are the result of decades of research and development, he said. "Salem Republic Rubber has been in business for almost 50 years," Phillips said. "We don't offer cookie-cutter solutions," he said. "We are a custom-engineered hose shop."

How to Avoid Common Shaft-Sleeve Problems

Shaft sleeves are cylindrical metal tubes designed to protect pump shafts from erosion, corrosion and wear at critical points, such as at the stuffing box. The shaft sleeve is a wear component, like brake pads on a car, and is designed to be more cost effective to replace than the shaft itself (like the entire braking system).

A slurry pump user recently discovered during an inspection that dirty seal water had cut their shaft sleeve in half, causing a leak. As a temporary measure, the millwright tightened the sleeve and moved it inward; however, this caused a secondary wear pattern and did not stop the leak. A second tightening prevented the sleeve from rotating and caused a horizontal wear pattern in one location. By this point, they should have realized that the sleeve was beyond repair. If wear patterns have already formed on the shaft sleeve, moving it will only worsen the wear and cause new wear patterns to form in the area relative to its original cause.

To better understand this, prep plant managers should think of slurry and contaminated sealing water like liquid sandpaper. Both can be highly corrosive and abrasive. Moving the shaft sleeve will only relocate the groove and initiate the generation of another one. Tightening the gland compresses the packing and reduces the cooling effect of the sealing water. Over-tightening it will make matters worse and can lead to component failure.

To prevent failure from occurring, maintenance personnel can take a few steps to diagnose and solve problems with the shaft sleeve before it wears out. This diagnostic should be a part of routine pump maintenance to avoid early sleeve replacement.

The first step is to inspect the sealing water system for adequate flow, pressure and quality. GIW recommended clean sealing water at a sustained pressure of 10 psi above the discharge pressure of the pump. The higher-pressure sealing water will prevent the pumped medium from weeping back into the stuffing box, thereby mitigating shaft sleeve wear. If the flow and pressure are within specifications, check the sealing water for corrosive properties and/or abrasive particulates. The shaft sealing system must be designed and applied according to the parameters for the pump.

If the shaft sleeve is worn beyond repair or leaking, it may be time to replace it. Fortunately, shaft sleeves are designed to be more time- and cost-efficient to replace than the entire shaft, making replacement a "no brainer" as far as cost and repair time are concerned. Shaft sleeves are available in different materials to combat all combinations of wear and corrosion.

If a shaft sleeve is worn to the point of leakage, a plant manager should consider replacing it. While replacing the sleeve is easier and less expensive than replacing the entire shaft, the process can interfere with production. Therefore, it's important to exercise best maintenance practices to extend the life of a shaft sleeve. Understanding what contributes to shaft wear and knowing the specifications of a particular pump related to flow, pressure, and sealing water could pay dividends in the long run.

This article was adapted from a GIW post on the KSB at www.ksb.com.

BY JESSE MORTON, TECHNICAL WRITER

Caption: Above, the onboard computer and display for the V2 non-nuclear slurry-density meter. (Photo: Red Meters)

Caption: Above, a 550-mm hydraulically actuated Flowrox pinch valve in a tailings system at mine site in Africa. (Photo: Flowrox)

Caption: Above, Salem Republic Rubber Co. offers custom tube-lining thickness on its Mining Hose. (Photo: Salem Republic Rubber Co.)

Caption: Tightening the gland compresses the packing and reduces the cooling effect of sealing water and over-tightening will only make matters worse. (Photo: KSB/GIW)
COPYRIGHT 2019 PRIMEDIA Business Magazines & Media Inc. All rights reserved.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2019 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:SLURRY PUMPS
Comment:A Sector in Search of Answers: The latest slurry handling solutions indicate the core needs of miners facing uncertainty.(SLURRY PUMPS)
Author:Morton, Jesse
Publication:Coal Age (1996)
Geographic Code:0DEVE
Date:Jun 1, 2019
Words:3904
Previous Article:Exports Support Illinois Basin Producers: During a time of declining domestic demand, exports brought much-needed business and will likely continue...
Next Article:Primary Loading Tool Advancements: New models and systems could improve productivity.
Topics:

Terms of use | Privacy policy | Copyright © 2019 Farlex, Inc. | Feedback | For webmasters