Refinery

By Paul Gruhn

Dave Johnson is an engineer at an aging refinery experiencing an increasing number of incidents. After identifying underlying causes he pushes for improvements. The management at the top aren't thrilled with his proposals. Fixing the problems would cost money, not to mention corporate bonuses and, possibly, executive jobs. 

 

Tensions between both the public and the workers rise as a pattern of near disasters continues. When the refinery experiences a fatality, things come to a head. 

 

The union comes up with only one demand. Can it, will it, be implemented quickly enough to prevent the unthinkable from happening?

• Language: English
• Publisher: Untreed Reads
• Release date: Feb 21, 2023
• ISBN: 9798888600801

Book preview

CHAPTER 1

Joe Morris, a fresh cup of coffee in hand, plopped himself on the rolling chair behind the shop desk. He kept his work neat but after decades of use in the Houston refinery’s instrument department, the desk was grimy with age-old dirt. The computer terminal wasn’t much better, but it was functional. Joe saw a half-full box of donuts on the desk and smiled. He selected half a plain donut, dunked it in his coffee, and took a bite. Joe logged in with his free hand and looked at his schedule for the day. A work order to replace a level transmitter would be an easy first thing to accomplish. He wrote the manufacturer and model number of the device on his small scratch pad, finished his donut and threw the Styrofoam cup into the wastebasket. He walked to the storage shelves and pulled a replacement sensor.

Joe put on his jacket and slicker, protection against the cool and drizzling March morning. He took his toolbox, a multimeter, and the transmitter, and walked out to one of the pickup trucks. The keys were in the ignition of the ten-year-old vehicle that had ‘wash me’ written by a smudged finger in the grime of the tailgate. The diesel came to life and he turned the heater on. He let the engine idle for a minute, and drove out to the tank farm.

The level sensor in question was used on tank 51A, a rarely used utility storage vessel located on the north side of Highway 225. Joe parked on the access road and took his equipment. He was grateful the sensor was located near the base so he wouldn’t have to climb the cold, wet, and slick metal ladder to the roof. He unscrewed the transmitter cover, connected the multimeter, and found there was no signal at all. The device did appear to be dead. He closed two isolation valves connecting the sensor to the process tubing, disconnected the wiring, and replaced the sensor. After reconnecting everything, he checked the operation using simulate mode. Everything appeared normal. He opened the isolation valves, picked up the old transmitter and his tools, and walked back to the truck.

The old transmitter produced an analog output signal in the 4-20 milli-ampere range and had no predefined failure mode. While the model number of the replacement sensor was the same, the internal software and operation of the device was subtly different. The default failure mode of the new transmitter was to fail-low—to 3.7 mA—if there were an internal failure. Joe, in his hurry to get of out of the cold rain, hadn’t bothered to check this detail. He was unaware the control system the sensor was connected to wasn’t configured to detect or alarm such an out-of-range condition.

One year later…

Lawson Ridley, Instrument Shop Foreman, checked his email. Word had come down from the refinery manager, through department managers, and now to him. Budgets needed to be cut ten percent.

Lawson muttered, Oh, good grief. As if we haven’t done enough already.

Lawson, who joined the refinery 20 years ago and had worked his way up the ranks, had been through budget cuts before. He had ideas of what might be cut, but it would be useful to bounce ideas off someone else. He looked out his office window and saw Tyrone Phillips, one of his most experienced technicians, talking with others at a workbench. Lawson walked up to the group. Eyes turned to him and their conversation stopped.

Lawson said, Tyrone, you got a minute? I’d like to talk with you in my office.

Miles replied, Sure, boss.

Lawson turned back to his office. Tyrone looked at the others, raised his eyebrows, and shrugged his shoulders. Lawson waited for Tyrone to enter. Tyrone sat and Lawson closed the door.

Lawson said, We’ve been dealt an ugly hand. Word’s come down from above we have to cut budgets ten percent. I’ve got some ideas, but wanted to bounce a few things around with you.

Tyrone sighed and said, I guess you’re not firing me then, huh?

Lawson chuckled and said, No, I’m not. We’ve had to let people go in the past. We’re relying on contractors more. You know I’ve fought against staff cutbacks every time.

Yeah, I know. But times change, plant managers change, priorities change.

Lawson nodded and said, I hear you.

Tyrone said, Boss, you see the financials, I don’t. I wouldn’t know what to suggest.

I’m not asking you to. I’ve already got some ideas. I just wanted to bounce them off you.

What do you have in mind?

We’ve been testing safety devices to check they’re working. Periodic testing’s a significant cost. What do you think are the lowest risk items?

Tyrone thought for a moment. We’ve been testing the transmitters in the tank farm every year. I can’t recall the last time one’s ever failed. Besides, the control system now calculates material balance in those tanks. The operators would be able to tell if a transmitter were to fail. Plus, there’re dikes around each tank to contain a spill. Overall, that sounds like a pretty low risk scenario. The tank farm’s certainly lower risk than the rest of the refining processes.

Lawson nodded and said, I agree.

The two sat in silence for ten seconds. Tyrone didn’t want to offer any additional suggestions.

Lawson said, We’ve already cut back on hiring. Our people know what we’ve got and how to work on it. We could cut back on our training. We could require the contractors document their people are qualified.

That’s no skin off our back. Vendors are happy to come in and do free dog and pony shows. They’ll even provide lunch. We could get some free training that way.

Good point!

Lawson leaned back and said, Thanks, Tyrone, I appreciate your time and input.

Tyrone went back into the shop. A co-worker approached and asked, What was that about?

Budget cuts.

Oh, crap.

One year later…

Frank Carlberg left his home in Pasadena at 6:30 a.m. on a warm and sunny April day with a refreshing low humidity uncommon in Houston. There wasn’t a cloud in the sky. Traffic was light so he arrived at the refinery in fifteen minutes. He found an open space in the gravel lot to park his pristine white three-year-old Ford F150 pickup. The truck sported an empty gun rack in the rear window, a popular accessory in Texas. However, company policy forbid firearms on the property, including the parking lot. Frank picked his lunch bucket off the passenger seat.

As he walked toward the entrance gate, his boots crunched on the gravel. Frank was one of dozens to go through the security turnstile that morning. He pulled his electronic badge from his shirt and held it up against the card reader, heard the metallic click, and pushed through the turnstile. It was a five-minute walk to the control room. He slid lunch into a locker, picked up his mug, and walked to the machine where a fresh pot was brewing with a half-full carafe on top. He filled his cup and went into the control room.

The twenty by fifty-foot room smelled like a damp, oily rag. It was kept dimly lit because bright lights made the dark screens harder to read. Chris Davis was seated at the supervisor station near the entrance.

Frank walked to the other end of the room and wheeled one of the chairs over next to Bill Collins.

He sat and said, Mornin’ Bill. What’s up?

Mornin’. It’s steady state. A tanker’s being offloaded into tank one-oh-one. We’re drawing from that same tank to feed the atmospheric distillation column.

Frank said, Sounds like a weird combination.

It is what it is. Other tanks already have product in them.

Any alarms? He looked up at the annunciators on the wall. Beyond the typical number of standing alarms, not really.

The annunciator panels were more than 40 years old. They consisted of rows of three by five-inch rectangular boxes with plastic covers each with different wording etched in it. When an alarm occurred, a light would turn on inside the box. Different colors represented different criticality of alarms. About a quarter of the nearly two hundred indicators were lit.

Frank said, Same crap, different day, huh? I wonder what it must have been like back when the annunciators were the only indicators? Everybody could see them and there weren’t so many.

Frank had been there twelve years, Bill ten more. Bill quipped, What, you don’t like having ten times more alarms now? They’re essentially free. They’re built into the control system. Nobody seest hem but us.

Frank snorted, No, I don’t. I don’t think you do, either. I know people meant well at the time but more isn’t always better. The alarm floods we get now are almost impossible to deal with. My complaints have fallen on deaf ears. I don’t want to be responsible for missing an important alarm and having an accident!

Nobody does. Look, we don’t have it so bad. Would you rather sit here in air-conditioned comfort, or be outside baking in the Texas sun running the refinery manually like our granddaddies did?

Point taken. It’s all relative.

We’ll get the alarms under control.

I hope so.

Bill slid the logbook to Frank who spent a quiet minute glancing through it. Frank noted the distillation column primary pump motor was running warmer than usual. Now that the day shift was coming on, he made a mental note to call a maintenance technician to check it out. Frank remained next to Bill for five minutes to observe.

Bill asked, You ready?

Yeah.

Okay, you’re in control.

With that, Bill left the control room.

Fifteen minutes later Frank looked at the shift log to see who was in the area. He radioed Doug Franklin, a Maintenance Technician. Doug, the atmospheric distillation column primary pump motor’s running hot. Can you check it out?

How bad is it? I’m working on a valve right now.

It’s not in alarm just yet, but it’s getting close.

Understood. That’ll be number three on my list. I’ll see what I can do.

✽✽✽

At 8:30 a.m. Allen Parks, one of the Process Safety Engineers, came into the control room with half a dozen employees in tow. The group remained near the entrance as Allen approached Chris.

He asked, Chris, you got a minute?

Sure. What’s up?

I’m leading one of our process safety studies. The team had questions about control rooms and screens. I figured it’d be best for them to see things for themselves. Would you mind spending a few minutes answering some questions?

Chris preferred not to have outside distractions while on duty, but these were company people and they were doing something he realized was important.

Sure. It’s pretty quiet now. Can we keep this to just a few minutes?

Yeah, that’s fine. Thanks.

Allen waved the group over and they gathered in front of Chris’s station.

Chris, could you give us the basics of what’s going on with your screens?

The control system screens show simplified graphical representations of the refinery. They’re laid out similar to piping and instrument diagrams; you’re all familiar with those. These screens are in color. The graphics are overlaid with numbers indicating temperature, pressure, level, and flow. That’s to show important information in all the tanks, pipes, pumps, and distillation columns.

Someone asked, How many different screens does it take to show all that for the whole refinery?

Hundreds. Operators don’t have to look at them all. They spend most of their time on overview displays. They’re only responsible for a certain area of the refinery, not the whole thing.

Someone else asked, The control systems are computerized, right?

Yes.

Isn’t everything run automatically?

Yes, at least most of the time.

Why display all the numbers? I mean, what’s an operator supposed to do with all that?

It’s all shown because operators are expected to know if things are running properly. At times they need to take manual action.

I’m sorry, but how’s an operator supposed to know by looking at hundreds of numbers? Do they know what the numbers should be for every variable? I mean, just displaying a number is raw data, it’s not meaningful information.

Chris replied, Well, maybe it’s not meaningful to you right now. Over time, it is to the operator.

Over time? Don’t get me wrong, I’m not trying to be combative here. We’re all on the same team. But how much time? I mean, I’m seeing shapes, lines, numbers, and different colors. I’m an engineer, but it all looks pretty confusing to me.

I’ll admit the screens may seem intimidating at first. People get used to them. Operators learn what it all means. Most of them have been here for years. I’m not saying it’s perfect, but this is all I’ve ever known.

Allen said, Okay folks. That should be enough. We should let Chris get back to work. He turned and said, Thanks, Chris.

Allen and his team left the control room to continue their meeting.

✽✽✽

Gary Baker’s co-workers were celebrating his retirement in the refinery maintenance shop. The room smelled of oil, cleaning fluid, and pizza. Half a dozen boxes were spread out across a table. Two dozen workers were in the shop, more than half of them outside contractors. Gary put a slice of supreme pizza on his paper plate, poured himself an iced tea, and sat at a table.

Trevor Adams, a young contractor seated across from him, said, Congratulations on retiring, Gary!

Thanks, Trevor.

How long you been here?

More than forty years. I hired on right after high school. This place was booming back when I was a kid. He smiled and added, Not literally.

Wow! You never worked anywhere else?

Nope. No need to.

What was it like?

Gary smiled and said, Well, that’d take a few hours.

Yeah, sorry. Were there many contractors back then?

No, there weren’t.

What changed?

Back then the company liked to manage everything internally. We did our own training. I learned through an apprenticeship program, on-the-job training, and vendor classes. Over time, budgets, priorities, and outside pressures brought about change. We rely more on contractors now. Management thinks it cheaper. They’re bean counters.

Huh? What’s that?

Take beans. Somebody’s plants ’em, somebody grows ’em, somebody harvests ’em, somebody ships ’em, somebody sells ’em, and somebody buys ’em. And damned if somebody doesn’t feel the need to count ’em. That’s a bean counter. The worst part is, they think they’re the most important person in the whole chain.

That’s pretty good. I’ll have to remember that.

Get used to hearing it a lot.

Trevor asked, Were the jobs similar then?

Technology has changed a lot over time. There were different positions open during the boom years. I’ve always been a hands-on, mechanical sort of guy. The maintenance shop had appeal. I became a pump specialist.

I’ve worked on pumps. You got forty years on me! What sort of pointers would you give?

Gary thought for moment. When something fails, don’t just replace it. Ask lots of questions.

Why not just replace it?

When a fuse fails, does that mean there’s something wrong with it?

No.

When you replace a fuse with a new one, and it blows too, the fuse isn’t the problem. The same applies to a pump. Pumps are a lot more expensive and time consuming to replace!

I never thought of it that way. What sort of questions would you ask?

When did the problem first occur? Was it sudden, or did it degrade over time? Has it happened before? Did it sound like there were marbles going through the pump?

Marbles?! What’re you talking about?

Pumps fail for lots of reasons. Cavitation’s a common one. It sounds like a gas engine when the octane’s too low. I won’t get into all the details, but cavitation creates actual pits in the metal. It can do a lotta damage over time. It’s generally not even the pump’s fault. It can usually be traced back to a bad system design, or bad design assumptions.

What’ll you be doing in retirement?

Fishing, woodworking, spending time with grandkids, driving the wife crazy. Typical sort of shit I guess.

Trevor laughed and said, Good for you! Enjoy your retirement! Trevor looked around and said, I can see others would like to talk with you. I’ll move on.

Gary and the others enjoyed the rest of their lunch break.

✽✽✽

Frank Carlberg got a refill of coffee at two in the afternoon. As he sat down there was an audible alarm from his control station. He pressed a button, which silenced the beeping, and moved to the alarm screen. A new line read, ATM DIST COL, PRI PUMP SHTDN, HI TEMP. Operators had gotten used to cryptic messages over time. This one meant the atmospheric distillation column primary pump motor had shut down due to high temperature. A few seconds later, additional alarms and messages came in.

He grumbled and muttered, Stupid system. If the pump motor shuts down, you don’t need to tell me there’s low speed and low flow.

Frank knew the importance of keeping the distillation column running. It’s the first processing unit in the refinery and if it shut down everything else would go down as well. He remembered the incoming crude to the unit was being offloaded from a ship that day and sent to a storage tank. From there it would go to the distillation column. Any potential loss of production would have a severe financial impact and he didn’t want to be responsible for that problem. He navigated to the appropriate screen and entered a command to start the backup pump, a redundancy for contingencies such as this. Frank started to monitor variables on other screens.

Frank got on the radio again. Doug, were you able to get to the distillation column pump motor?

Sorry, Frank. No. What’s up?

It just shut down. I started the backup pump. Could you or somebody check it?

Will do.

A low-level alarm came in on the distillation column a few minutes later.

Frank muttered, What the...?

He navigated back to the distillation column screen and tried to interpret the mass of numbers, colors, and flashing indicators. He noticed the backup pump was not running. Without incoming flow, the distillation column would shut down automatically, as it was ready to do. Without pumps there was little Frank could do. He called out to his supervisor at the other end of the room.

Chris! Something’s wrong here. I could use some help. Chris walked over and said, What’s going on.

Frank reviewed what had happened and ended with, I have no idea why the backup pump didn’t start.

Well, that ain’t good. Without those two pumps, there’s not much we’re going to be able to do. The unit’s going to have to come down.

I get that. The crude’s coming from a storage tank being filled from a tanker right now. Without flow going to the column, that tank might overfill. We’ve already got product in other storage tanks. We’ve got to divert that crude somewhere. We can’t just tell the tanker to stop. It’s got a schedule to meet.

What about diverting the tanker flow to utility storage tank fifty-one-A?

That’d work for now.

He entered commands to divert the flow. The two remained busy with the impending shutdown.

Unknown to everyone at the time, the level sensor on tank 51A had failed a month earlier. The output of the device went to its default value of 3.7 milli-amperes, but the control system was unable to detect and respond to the out-of-range condition. The control system and operator screens showed the last available reading from the transmitter as zero. As a result, no one knew tank 51A was almost full. The tank started to overflow from its vent ports within an hour. The tank farm was unmanned, so no one noticed the developing situation. Frank was too busy to check whether the transmitter output indicated a change in level as the tank was being filled.

Joe Morris was alone in a company pickup truck and headed back to the maintenance shop. He drove through the tank farm, the largest area within the refinery. It consisted of almost one hundred different sized tanks, most of them massive, that held the products used and produced by the refinery. Each was surrounded by an earthen berm, also known as a dike, to contain possible leaks. There was liquid within the dike around tank 51A. Joe stopped the truck and could smell the rotten egg sulfur odor of sour crude. The overflow vents at the top of the storage tank gushed oil. The truck’s diesel engine started to race, but Joe’s foot wasn’t on the gas pedal.

He muttered, What the hell?!

The engine breathed in fumes from the pool of crude and raced faster.

Joe turned the engine off, but the diesel continued. Oh shit!

He leaped out of the truck and ran as fast as he could. Fifteen seconds later, he heard the truck backfire. The resulting vapor cloud explosion sounded and felt like a large bomb. It propelled Joe off his feet and he landed several feet away. It took him a few seconds to regain his senses. He twisted around to see a fireball and a pillar of billowing black smoke in the sky.

He turned his portable radio to the emergency frequency and shouted, Explosion in the tank farm! I repeat, explosion in the tank farm! A huge fire now! Hit the fire alarm and call a foam truck!

Ben Matheson, the refinery Firehouse Chief, was reading a technical manual in his second-floor corner office. The explosion flash caught his attention. A half second later the blast wave rattled his office windows. Based on direction and distance, he had a good idea of where it occurred. The refinery-wide fire alarm siren sounded. Ben looked at his computer screen and confirmed it was the tank farm. He ran down the stairs to where the fire trucks were parked.

Previous budget cuts reduced the size of the refinery’s permanent fire fighting force. Refinery employees volunteered to learn fire- fighting to make up for the loss. They rushed to the firehouse to suit up.

Ben grabbed a bullhorn and announced, It’s an explosion in the tank farm. Right now we’re dealing with a fire. Keep your breathing apparatus with you at all times. Pay attention to your gas detectors. Listen to your radios. Let’s take that first foam truck. I’ll drive my truck. Some of you can come with me.

The team gathered in the two vehicles. From the time the explosion happened, it took them ten minutes to arrive. The dike surrounding tank 51A was full of liquid on fire. The top of the tank burned too,