Chemical industry automation
First the permissive. Then the valve.
Electrical schematics, control panels and software for batch plants, from the tank farm to drum filling: sequences that don’t skip a step and, for every batch, a report on how it went.
Batch plants
Here you don’t scrap one part. You lose the whole batch.
A valve that opens at the wrong moment, a component dosed twice, a temperature ramp that’s too steep: in a batch plant the mistake doesn’t stop at one part. It ends up in two thousand liters of product to rework or dispose of. And where there are solvents, safety comes before quality. That’s why the control system runs on permissives: a step starts only if the one before it finished properly, and a record is kept of how each one went.
On these plants we have worked in four places: storage and dosing, reactors, mixing and dispersion, packaging and drum filling. We supply the electrical schematic, the panel, the software and start-up: to the plant upgrading the controls on a system that can’t be down for long, and to the company that builds the system.
Through the plant
Six areas, seen from the control panel. What gets measured, what gets interlocked.
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Raw materials · Tanks
The load goes only into the right tank.
Before the tank truck unloads: grounding clamp connected, valves confirmed in position, room for the whole load. Level is measured continuously; overfill has its own probe, which stops the pump. For solvents, nitrogen blanketing.
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The components · Dosing
The valve closes before the final weight.
By weight, on load cells, or with a mass flow meter. The valve has two flow rates, coarse and fine, and closes early: what falls after the valve has closed is measured and corrected on every dose. An out-of-tolerance weight stops the sequence.
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The reaction · Reactor
Product temperature is in charge.
Cascade control: product temperature sets jacket temperature, with the recipe’s ramps and holds. In exothermic reactions, the reagent goes in only with the agitator running and the temperature below threshold; above it, dosing stops and cooling goes to maximum.
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The blend · Mixer
Viscosity is read from the motor.
Order of addition, times and speeds are in the recipe. Manual additions are confirmed on the HMI, with the weight read from the scale. The drive sets the speed and measures torque: when the product thickens, it shows in the current draw. With the manway open, the agitator won’t start.
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The dispersion · Disperser
Tip speed is what counts, not rpm.
The sawtooth blade runs at around twenty meters per second: the recipe holds the tip speed, and the program calculates the rpm from the installed blade diameter. It runs only when lowered, with the tank in place. In the bead mill, flow rate, pressure and outlet temperature are in charge.
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The drum · Drum filler
The lance rises with the level.
Drums, totes, cans: filling is by weight, net of tare. If the product foams or is flammable, the lance goes down to the bottom and rises with the level. Without grounding and without fume extraction running, nothing starts. On the label, batch and weight.
Your area isn’t one of these six? Describe it to an engineer.
Where you start
Not everyone starts from scratch. Tell us where you are: we start from there.
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New plant
From design to the first good batch
A tank farm, a dosing room, a reactor with its utilities. From the P&ID and the instrument and valve list come the electrical schematic, the panel and the software. The sequences are written phase by phase with the people who know the product, before any programming. Then testing in our workshop and start-up at the plant.
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Plant to redo
The controls change, the plant stays
A sound reactor with a discontinued PLC, a dosing system still corrected by hand, a supervisory system on a computer nobody dares shut down. Tanks, valves and instruments in good order stay where they are. The new panel arrives tested with its sequences; the shutdown is set for a campaign changeover, and you restart with the same recipes as before.
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Just one piece
You’re missing one part: we do that one
The electrical schematic for a dosing room that’s already designed, the panel for a disperser, the software for a drum filler, the HMI screens for a reactor. We work from your documents, alongside your suppliers. The scope of supply is put in writing at the start: what we deliver, what stays with you or with the machine builder.
Questions
Questions from the control room.
They apply to almost every plant. For yours, we need to see it.
We have classified areas because of the solvents. How do you handle them?
We start from the area classification, which is the responsibility of whoever operates the facility. The panel sits in a safe area; the only devices that go into a classified area are those rated for it, with intrinsic safety barriers on the signals where needed. On the schematic, every component in a classified area can be identified.
The reactor’s PLC is no longer available. How long will the plant be down to replace it?
It depends on how much is prepared beforehand. The signals are surveyed with the plant running, and the panel is built and tested in our workshop with its software. What’s left for the shutdown is the connections, testing the signals one by one and the first batches. We agree on the window around your production schedule. How we work on an existing plant
The recipes are on paper, and in the shift supervisor’s head. Where do we start?
From how the work is done today. The recipe is written with the people who run it, one step at a time: quantities, temperatures, times, and what happens if a step fails. Then it goes into the system, and only authorized users change the parameters. Manual additions stay, guided by the HMI.
A customer disputes a batch from six months ago. What can we pull up?
The report for that batch: recipe used, raw-material lots, quantities dosed next to the target quantities, temperature curves, phase durations, alarms and operator actions, with time and user. How long to keep it and whether to pass it to the ERP are decided at the design stage.
We lose power, or compressed air, in the middle of a batch. What happens?
Every valve has a fail-safe position, decided at the design stage with the people who know the process: with no air or no power, it goes there on its own. When air or power comes back, the plant doesn’t restart by itself. The HMI shows where the batch was; whether to resume or discharge is up to whoever is running the plant.
Our instruments and valves are different brands and different ages. Can they stay?
The ones in good condition, yes. We read them through their own signal, analog or networked, and at testing we check the wiring and full scale of each one. We replace what’s no longer reliable, has no spares or isn’t rated for the area it’s in.
After start-up, a sequence hangs and we can’t tell why. Who do we call?
Us: the person who wrote those sequences answers. Support is included for the first twelve months. Over a secure remote connection that you authorize us to use, we look at the phase, permissives and alarms from Mesero, together with you.
Before the quote
Start with the P&ID. Even an old one, even in pencil.
The P&ID for the area. If it’s gone, a few photos of the plant.
How many valves, how many motors, how many measurements: a handwritten count is enough.
What has to change: dosing that isn’t repeatable, batches with no data, spares you can’t find. And whether there are classified areas.
Diagrams, lists and photos can be uploaded in the form. An engineer reads them and replies within 1–2 business days.