Hexagon for correctional facilities — Converter + SMOX

The Hexagon solution

Two technologies, one chain inside the walls

Hexagon Technology Ltd designs plants that leave nothing to landfill. For a correctional facility the chain is short and entirely internal: waste from cells, kitchens, offices and the infirmary enters the CONVERTER®, which in half an hour sterilizes it and reduces it to a dry, odourless fuel; that fuel feeds a custom-sized SMOX module, which oxidizes it without flame and returns heat for the boilers and electricity. What remains is an inert white ash.

α · Converter

Sterilizes and reduces

Closed chamber in slight depression, 30-minute cycle, −80% volume: municipal and medical waste treated on site, no sorting.

σ · SMOX

Turns it into energy

Slow flameless oxidation and gas combustion at 1000 °C: about 80% of the waste's energy recovered, emissions far below EU limits.

π · Integration

One plant

Hexagon integrates the two machines, the heat recovery to domestic hot water and the generator: sizes from about 1 tonne a day upwards.

🌱 · Greenhouse

Closes the loop

The 40 °C heat, the CO₂ and the plant's water feed a controlled-atmosphere greenhouse: vegetables for the kitchens, grown by the inmates.

Why prisons

Eight benefits only a correctional facility fully appreciates

01

Perimeter security

Every vehicle in and out is a gate: contraband coming in, escape attempts going out. With on-site treatment, the garbage truck disappears from the perimeter — fewer inspections, fewer staff tied up at the gates, less risk.

02

No more bad odours

Converter and SMOX work in closed chambers in slight depression: no dust, no odours in the yards, the cells or towards the neighbours. The final residue is an inert ash, not a waste.

03

Medical waste on site

The infirmary produces infectious waste that today travels with dedicated, costly transport. The CONVERTER® H range sterilizes it directly in the facility, as already in hospitals; SMOX recovers its energy.

04

Work and training for inmates

The plant runs with few people and no special licence: ideal for work and re-entry programmes — a skill that can be used outside, in the growing environmental and energy sector.

05

Compliance and environmental goals

California mandates organic-waste diversion (SB 1383) and zero-waste targets for public facilities: the Hexagon chain turns the obligation into a measurable result — zero landfill and avoided CO₂.

06

Hot water and electricity from waste

SMOX heat pre-heats the domestic hot-water boilers — showers, kitchens and laundry for thousands of people, every day — and, in cogeneration, produces electricity for the facility. Energy that is paid for and thrown away today is produced inside the walls tomorrow.

07

Lower costs, right away

Fewer pick-ups, less transport, fewer landfill fees (among the highest in America, precisely in California and the Bay Area) and less purchased energy. The Converter arrives in a container, ready; the SMOX module is sized to the facility.

08

The greenhouse that closes the loop

The residual 40 °C heat, the CO₂ from combustion and the recovered water are exactly what a controlled-atmosphere greenhouse needs. Inmates run it and grow their own food: tomatoes, lettuce and vegetables for the kitchens all year round, a real trade and less food bought outside.

An example of what the technology can do

Demonstration example: a facility like San Quentin (California)

California's oldest prison (1852), on San Francisco Bay, today at the centre of the largest transformation of the American correctional system: the California Model, remaking San Quentin as a rehabilitation centre. We use it here as a demonstration example: this is what the Hexagon chain could do in a facility of this size.

~3,400inmates (design capacity 3,084)

~1,500+staff and operators (estimate)

1852California's oldest

SF Bayneighbours, decorum and odours matter

What it could do: the estimate and the reference configuration

Population served	~3,400 inmates + staff ≈ 4,500–5,000 people/day
Estimated waste generation	1.2–1.6 kg per person per day ≈ 5–8 tonnes/day (meals, cells, offices, maintenance)
Proposed configuration	1 × CONVERTER® MOB40 PLUS (two 400 L chambers in a 40' container, 200–300 kg/h) + 1 × CONVERTER® H200 for the infirmary + 1 × custom SMOX module (5–10 t/day) with heat recovery and generator
Energy in the waste	≈ 3.6 kWh per kg of municipal waste ≈ 18–29 MWh/day of energy content
SMOX recovery (≈ 80%)	≈ 14–23 MWh thermal per day — the equivalent of the hot-water needs of thousands of showers, the kitchens and the laundry
In cogeneration	≈ 3.5–5.8 MWh electric per day (150–240 kW continuous average) + 10–17 MWh thermal at 40 °C for domestic hot water
Residue	inert, carbon-free white ash with metals separated: zero landfill
Installation	Converter in a stand-alone container; SMOX module in the service area, connected to the existing heating plant
Operation	2–4 operators per shift — an ideal candidate for residents' work programmes
The greenhouse	40 °C heat, CO₂ and water from the plant → controlled-atmosphere greenhouse, indicatively 3,000–5,000 m²: vegetables for the kitchens, grown by inmates in work programmes

Method note: population and capacity from public sources (CDCR, press 2025); waste generation, energy content and yields are a first Pure Organica estimate based on EPA parameters and CONVERTER® and SMOX nameplate data (Hexagon technical documentation, June 2025), to be validated with a site survey and the facility's actual collection and energy-consumption data. The greenhouse area is indicative and must be sized on the heat actually available and on the facility's space.

Closing the loop

The greenhouse: inmates grow their own food

It is Hexagon's circular-economy model applied to a closed community. The plant produces the three things a greenhouse asks for: low-temperature heat (the 40 °C leaving the cogeneration unit), carbon dioxide (which plants turn into growth) and water. A controlled-atmosphere greenhouse, heated and fertilized by the plant, grows vegetables all year round regardless of the climate. Inmates run it: an agricultural training programme, a trade to use on release, and fresh vegetables in the facility's kitchens instead of those bought outside.

The Hexagon plant: waste-to-energy unit and greenhouse side by side

Aquaponic greenhouse: vegetables and fish with the plant's water

Pressostatic climatized greenhouse: growing all year round

Waste5–8 t/day from the facility

Converter + SMOXsterilizes, reduces, turns into energy

Heat · CO₂ · waterto the controlled-atmosphere greenhouse

Foodvegetables for the kitchens, grown by inmates

The loop closes inside the walls: today's waste is tomorrow's hot water, light and food. No trucks out, no landfill, a more self-sufficient facility — and a rehabilitation programme with a concrete meaning.

The Hexagon model: non-recyclable waste enters the Converter and becomes solid fuel for the power plant; the plant returns heat, CO₂ and water to the greenhouse (food), electricity and hydrogen to transport, oxygen to healthcare, sand and metals to industry (Hexagon Technology Ltd diagram)

What it looks like

The Converter arrives in a container; SMOX is built for the facility

The same Converter units already in service in military bases and camps in 25 countries — NATO code NCAGE AH649, ISO 9001/14001 and RINA certifications — and the SMOX technology with INDDIGO's TRL opinion and design to Directive 2010/75/EU: credentials federal administrations know how to read.