Mobile & Containerised Systems
Containerised Scrubbers: High Capacity that Travels
A wet gas scrubber that fits an ISO container envelope goes anywhere a container goes. No exceptional transport, no permits for an oversized load, no waiting.
Some emission problems do not sit still. A remediation campaign that runs for four months. A turnaround where the permanent scrubber is offline. A tank terminal handling a product it does not normally handle. A mobile thermal treatment unit that has to satisfy a permit in a different country every quarter.
For all of these, the constraint is not whether a scrubber can be built. It is whether it can be got to site, hooked up and permitted before the window closes.
01 Why the container envelope is the whole argument
A 40 ft container measures roughly 12.03 × 2.35 × 2.39 m internally, or 2.69 m high in the high-cube version. Stay inside that box and a piece of process equipment stops being a logistics project:
- It moves by road, rail and sea on standard equipment.
- It is handled by any crane, reach stacker or terminal in the world.
- No exceptional-transport permits, no escort vehicles, no route surveys.
- It arrives on a chassis, comes off in an hour, and stands wherever the customer has a hardstand.
Step outside that box and every single one of those becomes a phone call, a permit and a delay. On a campaign measured in months, weeks of mobilisation is not a rounding error.
02 Our geometry is already the right shape
This is not a design we had to invent. Our horizontal open-spray scrubbers are rectangular, low and compact by construction, because that is what the spray principle allows. Put the dimensions of installations we have actually delivered against the container envelope:
| Delivered installation | Dimensions (mm) | Capacity | ISO envelope |
|---|---|---|---|
| Odour scrubber, baking ovens | 5,000 × 1,250 × 1,750 | 8,000 Am³/h | Fits 40 ft with room to spare |
| Two-stage odour scrubber, roasting ovens | 4,000 × 1,500 × 1,500 | 20,000 Nm³/h | Fits 40 ft with room to spare |
| Scrubber, chemical surface treatment | 3,600 × 1,500 × 1,200 | 12,000 Nm³/h | Fits 40 ft with room to spare |
| Acid scrubber, fertilizer plant | 3,080 × 1,800 × 2,300 | 24,000 Nm³/h | Fits 40 ft |
| Fine-dust scrubber | 3,500 × 2,000 × 2,500 | 35,250 Am³/h | Fits 40 ft high cube |
| NH₃ and VOC scrubber | 7,200 × 2,200 × 3,200 · 14 t | 20,000–50,000 Am³/h | Flat rack or open top |
| Odour scrubber, roasting ovens | 7,500 × 2,000 × 2,920 · 9 t | 20,000–60,000 Am³/h | Flat rack or open top |
Read the fourth column against the third. A unit doing 35,250 Am³/h inside a high-cube envelope, at 400 to 500 Pa pressure drop, is a genuinely high specific capacity. And the units that step outside the envelope do so on height and width, not on length or weight — which means the skid layout is a design choice rather than a physical limit.
03 Four things that make a spray scrubber suit temporary duty
No packing to move, foul or replace
Because overlapping spray patterns do the gas–liquid contact work, random or structured packing is unnecessary. On a fixed installation that mainly buys you a low and stable pressure drop. On a relocatable unit it buys you something else: there is no packed bed to shift, settle or damage during transport, and nothing to unload and repack between deployments.
Low pressure drop means a smaller generator
Temporary sites frequently run on a diesel genset. Fan power is usually the largest single electrical load on a scrubber skid, and fan power is set by pressure drop. A structurally low pressure drop shrinks the generator you have to hire and the fuel you have to burn for the duration of the campaign. On a four-month job that is a real line in the budget, not a technical footnote.
Cassette construction means fast turnaround
Rectifiers and droplet separators are mounted in cassettes that slide into rails inside the housing. They come out through an access hatch, get cleaned with a high-pressure cleaner, and go back in. Every washing section has its own inspection hatch. For an asset that has to be cleaned and certified between one campaign and the next, this is the difference between days and weeks of downtime.
Built for peaks, not just averages
Counter-current open-spray washing absorbs irregular concentrations and peak discharges well. Campaign work rarely gives you a steady inlet. A scrubber sized only for the average is a scrubber that breaches its limit on the worst hour of the week.
04 Where a relocatable unit earns its place
- Mobile thermal treatment and incineration campaigns. Acid-gas removal downstream of a mobile oxidiser, where the feedstock is halogenated or sulphur-bearing and permit limits for HCl, SO₂ and HF have to be met.
- Turnarounds and shutdowns. Temporary abatement while the permanent installation is out of service, so production does not have to stop with it.
- Decommissioning and demolition of chemical plant.
- Tank terminals and product handling. Acid gases, ammonia, amines and water-soluble components during transfer, tank venting or non-routine operations.
- Soil and groundwater remediation. Off-gas from air strippers.
- Incident and emergency response. A leaking tank, an ammonia release, or a treatment step that has to exist by Friday.
- Digesters, landfill and wastewater treatment. H₂S and odour control during works or capacity peaks.
- Fertilizer, animal feed, rendering and food. Odour and ammonia, or temporary extra capacity while a permanent installation is built.
- Pilot and trial duty. Measure on your own gas, at your own site, before committing to a permanent installation.
05 Where a wet scrubber fits, and where it does not
We would rather tell you this before the quotation than after commissioning.
A wet scrubber is the right tool for
Acid gases such as HCl, HF, SO₂ and SO₃; ammonia and amines; H₂S; water-soluble VOCs including alcohols, ketones and organic acids; odour-forming components via oxidative washing; particulate and fine dust; and aerosols.
Not the right tool on its own for
CO₂; NOₓ without an oxidation or DeNOₓ step; CO; or poorly soluble hydrocarbons such as benzene. In those cases a scrubber is one stage in a treatment train, not the whole answer — and we will say so.
There is also a liquid side to plan for. A wet scrubber generates a purge stream carrying the salts and components it has removed. On a temporary site that stream has to be collected and disposed of or treated, and it belongs in the permit application and the budget from day one.
06 What we do
We design and build wet-scrubber systems for the reduction of harmful and odour-loaded gas emissions. Installations delivered range from 60 Nm³/h laboratory-scale columns to 80,000 Am³/h horizontal systems, in AISI 316L, PP, PE, HDPE and PVDF, handling HCl, HF, SO₂, Cl₂, Br₂, HCN, NH₃, ethylene oxide, acrylic acid, methanol, ethanol, fine dust and odour.
Every system is engineered around the gas that is actually there. Send us flow, composition, temperature and the limit you have to meet, and we will tell you what is achievable and what it takes.
Frequently asked questions
Why does fitting an ISO container envelope matter so much?
Inside a 40 ft envelope (about 12.03 × 2.35 × 2.39 m, or 2.69 m high-cube) a scrubber moves by road, rail and sea on standard equipment, is handled by any terminal, and needs no exceptional-transport permits, escorts or route surveys. Step outside it and each of those becomes a permit and a delay — which on a months-long campaign can cost weeks of mobilisation.
How much capacity fits within the envelope?
Delivered horizontal open-spray units reach 35,250 Am³/h inside a high-cube envelope at only 400–500 Pa pressure drop. Larger units up to 80,000 Am³/h travel on a flat rack or open top; they exceed the box on height and width, not on length or weight, so the layout is a design choice rather than a physical limit.
Why a spray scrubber rather than a packed column for mobile duty?
Vertical packed columns are six to eight metres tall and are site-built structures — they do not travel. The horizontal open-spray geometry is low and rectangular by construction, and has no packed bed to shift, foul or repack between deployments. It also runs at a low, stable pressure drop, which shrinks the diesel generator a temporary site has to hire.
How quickly can a unit be turned around between campaigns?
Rectifiers and droplet separators sit in cassettes that slide out through an access hatch, are cleaned with a high-pressure cleaner and slide back in; every washing section has its own inspection hatch. For an asset that must be cleaned and certified between jobs, that is the difference between days and weeks of downtime.
What can a wet scrubber not do on its own?
A wet scrubber is not the standalone answer for CO₂, NOₓ (without an oxidation or DeNOₓ step), CO, or poorly soluble hydrocarbons such as benzene — there it is one stage in a treatment train. Plan for the liquid side too: the scrubber produces a purge stream of salts and captured components that must be collected, treated or disposed of, and it belongs in the permit and budget from day one.