Overview
ARBOK-MarineSludge applies the Vacuum Cracking platform to MARPOL Annex I ship-generated oily sludge received at ports. Sludge is separated under deep vacuum, at ambient temperature, into a fuel fraction, clean water, elemental sulphur and a dry mineral residue — with no heating, no combustion, no reagents and no consumables. Ship sludge contains 40–50 % hydrocarbons, so the incoming stream that ports currently treat as a disposal liability becomes feedstock. A single modular unit processes the annual sludge output of roughly 233 vessels, with capacity scaling by adding units.
Applications
Primary use cases: port reception facility (PRF) operation for MARPOL Annex I waste; bunkering-hub sludge processing; terminal tank-bottom residues; scrubber (EGCS) concentrate; slops and bilge residues.
Outputs/uses: fuel fraction (blend component or finished bunker subject to spec), clean water, elemental sulphur, dry mineral residue containing vanadium and nickel.
Industries and users: port authorities, PRF operators, bunker traders, terminal operators, refineries at the gate.
Scale: modular containerized units; capacity scales linearly by module count. A Singapore-scale hub requires only a handful of modules.
Operating Principle
The boiling point of a liquid falls with pressure. Under deep vacuum, both water and the hydrocarbon fractions in the sludge boil at temperatures far below their atmospheric values, so separation that conventionally requires hundreds of degrees runs at ambient temperature.
The process follows a multistage route: sludge is drawn in and degassed under vacuum; water and light fractions evaporate while asphaltenes, resins and heavy molecules remain liquid, so the stream separates by volatility and density simultaneously; water and hydrocarbon vapours are condensed on separate circuits, with condensation heat recovered back into the evaporation stage to reduce net energy demand; contaminants are bound onto a proprietary graphene-like sorbent (TEG, thermally expanded graphite) produced by ARBOK and regenerated in a closed loop rather than consumed; and ash, catalyst fines, salts and metals are discharged as a dry mineral residue, with sulphur recovered as a separate dry product.
Vacuum draws sludge from source over a long reach without pressure pumps, removing the need for separate intake pumping.
Limitations: product specification on marine sludge feed requires laboratory confirmation (cetane index, lubricity, stability) before the fuel fraction can be sold as an ISO 8217 grade rather than a blend component; feed composition varies by vessel and separator performance.
Key Parameters
Conditions: deep vacuum; ambient temperature, equal to the incoming stream and surroundings — no heat is supplied. Energy: very low specific energy consumption, a small fraction of that required by thermal zero-liquid-discharge alternatives; efficient heat recuperation reduces net energy demand further.
Throughput: a reference module processes approximately 70,000 t/year of sludge (illustrative annual basis for the economics below); capacity scales by adding units.
Footprint: compact, fitting within a small quayside plot alongside a tank park for water, sulphur and fuel; long-reach vacuum suction serves intake points at a distance.
Consumables: none (TEG regenerated in closed loop). No membranes, filters, catalysts or reagents.
Liquid concentrate: none — closed material balance.
Typical yield per 1 t of ship sludge (45 % hydrocarbons / 45 % water / 10 % solids):
| Product | Per 1 t sludge | Per module/year (70 000 t) |
|—|—|—|
| Fuel fraction | 450 kg | 31 500 t |
| Water | 450 kg | 31 500 t |
| Mineral residue | 100 kg | 7 000 t |
Architecture and Components
Vacuum intake and degassing stage; deep-vacuum separation chamber housed in a modular containerized unit; separate condensation circuits for water and hydrocarbon fractions; heat-recuperation loop; TEG sorbent regeneration loop; sulphur and mineral-residue extraction; tank park; PLC/SCADA control. No boilers, furnaces, pressure pumps or reagent facilities. Concrete pad, open air; modular and scalable by module count.
Advantages
Technical: ambient temperature, no combustion, no consumables; closed material balance with no brine or liquid tail; long-reach vacuum suction removes the need for quayside pumping; a compact footprint fits within almost any port site.
Economic: converts a disposal liability (ships pay 10–25 $/m³) into products; processors already pay 50–70 $/m³ for clean oil-rich sludge, so the offtake market and price exist.
Environmental: no incineration and therefore no CO₂ from waste destruction (world fleet currently burns 300 000–650 000 t/year, releasing 1,0–2,0 million t CO₂ that performs no useful work); no liquid discharge; ZWD-compliant.
Strategic: lets a port discharge its absolute MARPOL PRF obligation as a production line rather than a cost line; removes the vessel's need to route voyages around sludge-capable ports.
Integrations
Port reception infrastructure, barges and quayside intake; terminal tank-cleaning operations; EGCS concentrate streams (excluded from the EU indirect fee under Directive 2019/883 and charged separately); refinery gate. Pairs with adjacent ARBOK platforms — ARBOK-VC (Vacuum Cracking), Arbok-VCBC (Bunker Cleaning), ARBOK-Port-Sludge-Cleanup, OILTRAP. SCADA/PLC ready.
Deployment & Operation
Steps: survey of port Annex I intake volumes → module sizing → site allocation and pad → installation → commissioning. Installation in weeks, not years. Continuous 24/7 operation, automated, minimal crew. Open air on concrete; heated enclosure in cold climates.
TRL
TRL 7. Evidence: the Vacuum Cracking platform is validated on petroleum feedstocks, including ballast-water treatment trials at a European refinery site, and containerised modules are operational in adjacent applications. Not yet evidenced: a deployed port unit dedicated to MARPOL Annex I ship sludge, and laboratory specification of the fuel fraction on marine-sludge feed. Remaining steps: port reference site, product specification package, offtake agreements.
Market Potential
World fleet generates ~3,6 million t of oily sludge per year (240 million t bunker × ~1,5 %). Of this, 300 000–650 000 t is incinerated on board; the remainder is landed ashore. Singapore alone recorded 42 603 bunker calls in 2025 (~117/day) and 56,2 million t of bunker sales; the fleet it serves generates ~843 000 t of sludge annually. MARPOL obliges every port to provide adequate reception facilities without undue delay, yet ~70 inadequacy reports are filed to IMO GISIS each year and the IMO acknowledges a long-standing PRF shortage. EGCS concentrate volumes will rise until the OSPAR closed-loop discharge ban of 1 January 2029. Roughly 51 modules would cover the entire world sludge volume.
Typical Project Economics
Per tonne of sludge processed: fuel fraction 450 kg × 350 $/t = 157 $; mineral residue 100 kg × 100 $/t = 10 $; reception tariff ~1,1 m³ × 15 $/m³ = 16 $; OPEX 25 $/t. Net ≈ 159 $/t.
Per module (70 000 t/year): fuel fraction 11,03 M$; reception tariff 1,16 M$; mineral residue 0,70 M$; OPEX −1,75 M$. Net ≈ 11,1 M$/year.
Commercial models: BOOM (Build-Own-Operate-Maintain) as the base offer — the port invests no capital, provides site, logistics and power, and commits to a defined annual sludge volume at a fixed price over a 15–20 year term. Alternatives: outright equipment sale with 5–7 year payback, or BOT. Mandatory product buyback at fixed prices removes offtake risk for both parties (same structure as ARBOK CleanSea).
Risk Factors
Fuel-fraction specification on marine-sludge feed unconfirmed — determines whether the product sells as an ISO 8217 grade or only as a blend component; feed composition variability between vessels; port authorities' conservatism and long procurement cycles; hazardous-waste licensing per jurisdiction; offtake agreements for fuel fraction and mineral residue must be secured; no dedicated port reference site yet.
Related Technologies
ARBOK-VC (Vacuum Cracking) · Arbok-VCBC (Bunker Cleaning) · ARBOK-Port-Sludge-Cleanup · OILTRAP · ARBOK CleanSea