Frac sand safety has become an important topic lately with all the concerns about silica dust being inhaled by workers. Thankfully, there’s been a push for better training, equipment, safety policies and procedures.
Implementing these changes can often lower productivity, but this isn’t the case with the introduction of Telebelts. They’ve actually made it safer while increasing productivity at the same time.
We ended the last section by mentioning there were 3 main areas of concern when using pneumatic systems. (Pressure, frac sand storage, and speed.) So let’s take a look at each one to see the advantages of using a Telebelt over conventional pneumatic systems starting with Pressure.
Before we get into that take a look at this short video of what the frac sand dust looks like while unloading at night.
Pressure
The first main area of concern is frac sand off-loading under pressure. Concerns in this area are handling high pressure lines, spillage and frac sand silica dust. We’ll also throw in product quality issues even though it’s not a safety concern, it still deserves mention.
Hazards of pressurized lines
There’s been many documented cases of injuries and near misses with pneumatic systems. They can be caused by blowouts in the line, fittings coming loose, or removing pressurized lines that have plugged off. I personally witnessed a line blowout that sent an employee to hospital with a broken tibia and fibula. The accident was preventable, but it still happens.
Frac Sand Safety. Silica dust exposure can lead to silicosis of the lungs. Full face masks are now required throughout most of the fracturing industry.
Silica Dust (Silicosis)
You’ve probably heard this saying about fracturing sand, “If you breath it in, it doesn’t come out.”
This is the single most important reason for the push for improvements in frac sand safety. It’s been known for many years and ignored for far too long. Frac silica dust clouds linger like a fog. Full faced masks have to be used around the immediate area.
Pneumatic systems unloading under pressure force all the silica dust into the air while moving the sand with telebelts create very little dust.
Microscopic flecks of crystalline silica are dangerous particles smaller than 2.5 micrometers (PM2.5). They’re about one-twentieth the width of a human hair and can become permanently lodged in the lung tissue. I’ve recently become aware of companies now providing full body suits, so the dust doesn’t touch any part of your skin.
Improved Frac sand safety led to dust control systems, but they’re not 100% effective. Everything from equipment failure to operator issues can leave workers exposed to silica dust.
The dust collection systems I’ve seen in the field help reduce the dust, but aren’t 100% effective, or reliable. Like any equipment, they’re only as good as the operator using it. I’ve seen these dust collection systems partially or completely fail while the unloading continued.
Keep Reading Frac sand Safety…..
Spillage of sand
Over the last few years the blower volume capacities have increased. Although this helped cut down on unloading time, it’s alternatively led to more spillage and dust.
High and low blower capacities both have their own problems.
Smaller blowers have the issues of “Plugging off”. A plugged line usually means pressuring down and cleaning the line out which means more sand on the ground and lost time. Plugged lines are pressurized making them a serious safety hazard.
Increased blower capacities have a much less chance of plugging off. The downside is they continue to blow the sand out the top lid and over the top of the vessel. Inattentive or inexperienced operators can create quite a mess and increase silica dust in the area. The problem became worse as the jobs got bigger and more vessels were needed. It became difficult to monitor the unloading progress.
Frac Sand Safety. As fracturing jobs got bigger, stacking sand vessels became a challenge for operators of pneumatic systems.
Effects of pressure on specially coated sand
Maximum conductivity is achieved by preserving the quality of the sand. Less fines and silt means reduced turbidity and can translate into millions of dollars in revenue over the life of a well. This makes preserving the quality of curable resin coated sand very important. Telebelting provides a system with no pressure thereby preserving sand quality.
There are 2 main problems with curable resin coated sands and pneumatic systems. The first one is a problem of following directions. It’s clearly noted on each loading ticket that coated sands should be offloaded at reduced pressure. (Maximum pressure of 5 or 6 psi.)
Unloading at a lower pressure prevents the coating from being blown off the sand. If these directions are followed it then doubles the unload time. Unloading a trailer at this rate can easily take 2 to 3 hours.
The second is an issue for not following the directions.
Many drivers either fail to recognize, or ignore these directions and don’t take the proper measures when unloading. This in turn will affect the quality of the product.
Pressurized pneumatic systems unloading under high pressure can strip these curable resin coatings off the sand. A reduction in bonding capability leads to an increase in proppant pack migration, flow back, and a reduced ability to resist cyclic stress.
Frac Sand Safety. Most people think of frac sand like the kind they find at the beach. This is a resin coated frac sand being loaded from the plant.
Advantages of Telebelting over pressurized unloading
Telebelts have been a positive change to the industry by eliminating the hazards of numerous pressurized lines. Eliminating pressure leads to a significant reduction in the health hazards of drifting silica dust. It can also be done with much less spillage.
Preserving curable resin coatings is another benefit over conventional methods as it leads directly to increased well conductivity.
They’re also significantly quieter than PTO driven blowers. These blower units can wake up sleeping workers, medics and consultants. Many locations don’t allow blowers to be operated at night near residential areas. Hearing protection is a must with pneumatic systems.
Safety in the Oil and Gas industry is a high priority and unloading without pressure has been a step in the right direction. Let’s move on to the next section for some more comparisons.