How We Squeezed a 5-Ton Pulses & Sesame Cleaning Plant into a Tight Factory in Addis Ababa
Facing low ceilings and limited floor space, Ethiopia's third largest bank needed a custom solution. See how Zhengzhou Hawking Industry redesigned its standard 5TPH pulses and sesame plant to fit perfectly without building renovations, achieving flawless kidney bean cleaning in the first trial.
The site was a problem before the process was. A 5 ton per hour cleaning plant for both pulses and sesame, inside an existing building in Addis Ababa with low ceilings, narrow column spacing, and a hard rule from the client: no structural renovation. Here is how the line was re-designed around the room.
The brief had a hard constraint attached
The project was financed by one of Ethiopia's largest banks, which meant the plant had to go into an existing industrial shell that had already been approved and valued. Concrete work, roof raising and new openings were all off the table. The usable floor area was a little under 200 square metres, the clear height under the roof trusses was 4.2 metres, and two rows of columns cut through the middle of the space.
On top of that, the line had to handle two very different materials:
Kidney beans and other pulses - relatively large, heavy, free-flowing, cleaned mostly by size and colour.
Sesame - tiny, dense, prone to fluidising, and cleaned mostly by density and air, with completely different screen and aspiration settings.
Why the standard plant did not fit
Our standard 5TPH pulses line is laid out horizontally: it is easy to maintain, easy to see, and it wants about 26 metres of straight run. This building had 19. The de-stoner and gravity separator also sit on a conventional 2.6 metre service platform, which left nothing under a 4.2 metre roof once ducting and the elevator head were accounted for.
What we changed
Standard design | Modified design for this site | Why |
|---|---|---|
Horizontal single-level layout | Split-level layout with a compact mezzanine positioned between the column rows | Used vertical space instead of floor length |
2.6 m service platform | 1.8 m low-profile platform with side-access maintenance hatches | Cleared the 4.2 m roof trusses with ducting room left over |
Standard head-room bucket elevator | Short-pitch elevator with a reduced head section | Fit under the trusses without cutting the roof |
Fixed screen decks | Quick-change cassettes: one cassette set for pulses, one for sesame | Changeover in about 20 minutes with no tools and no recalibration |
Single aspiration setting | Dual-range airflow with a stored sesame profile | Sesame needs far gentler air than beans or product is lost |
Skid-mounted frame, welded on site | Pre-assembled modules bolted together on site | No drilling, no anchors into the valued slab, nothing permanent |
The line still contains the same core stages our standard plant uses - pre-cleaner, density de-stoner, gravity separator, a compact colour sorter sized for the 5TPH throughput, grading and bagging - but arranged vertically rather than in a row. We produced a full 3D model of the finished installation and walked the client's engineers through it before manufacturing started, including a maintenance-clearance check: every filter, screen and drive can be reached without dismantling a neighbour.
The first trial
Installation took nine days. The commissioning run used kidney beans, the crop the client was most worried about, and the line was brought up to full 5TPH on the first attempt. There was no recirculation, no second pass, and no adjustment to the building. Finished purity measured 99.6%, with stones and discoloured grains removed in a single pass.
The sesame profile was commissioned the following week. It required lowering the air volume and swapping the screen cassettes, and it also ran clean on the first trial - which, for sesame in a constrained space, was the result we were least confident about.
Results
Footprint: the complete 5TPH line occupies about 190 square metres, including the mezzanine and maintenance access.
Civil works: none. No slab penetration, no roof work, no openings.
Throughput: 5 TPH on pulses, 3.5 - 4 TPH on sesame (sesame is denser and feeds differently).
Purity: 99.6% on kidney beans at first trial.
Changeover: roughly 20 minutes between pulses and sesame.
Installed on time: nine days on site, first commercial lot run on day ten.
'We were told the building was too small for a proper line. Hawking's engineers modelled it, moved the plant upward instead of outward, and ran our kidney beans clean on the first trial without touching the structure.' - Project Engineer, Addis Ababa
If you have a difficult room
Most cleaning plants can be re-arranged to fit an awkward building - the process stages do not change, only the geometry does. What we need from you is simple: a dimensioned floor plan, the clear height to the lowest obstruction, the position of columns and doorways, your product list and your target throughput. We will model it and tell you what fits before you commit to anything. See the colour sorter and cleaning equipment range for the machines that go into these layouts.