ENE · Waste-to-energy
Waste-to-energy
Two routes out of the same problem. Thermal treatment for what will burn, anaerobic digestion for what will not — both turning a disposal cost into generation.
Overview
Overview
Waste-to-energy sits at the join between our environment and energy practices, and it is usually where a project's economics turn positive. A waste stream that has to be paid to dispose of becomes a fuel; a treatment plant that consumed power becomes one that exports it.
There are two distinct routes and they suit different feedstocks. Thermal treatment — separation followed by high-efficiency incineration with heat recovery — handles mixed and calorific waste. Anaerobic digestion handles wet organic material: sludge, food waste, agricultural residues and animal manure.
Our waste-to-energy services cover biogas project development, anaerobic digestion engineering, organic waste energy recovery, sludge-to-energy, agricultural waste and animal manure energy recovery, food waste energy recovery, waste incineration energy recovery, waste heat recovery, steam generation from waste and electricity generation from waste.
Detail
The thermal route
Waste separation
Our leading-edge separation technology works with both selected waste and unsorted municipal waste, downstream of mechanical treatment, through a mechanochemical process that alters the molecular structure of the material by micronization. That makes the waste available for combustion and contributes to its stabilisation and sanitation. The plant can sit downstream of the shredding system or be used as a mobile unit.
High-efficiency incineration
Municipal solid waste serves as the primary fuel source for a turbine or gas engine. The flue gas recovered from that turbine or engine is used to superheat the steam entering the water turbine or the general water supply system. The result is a combined cycle power plant, or cogeneration of heat and power, using municipal solid waste fuel at a higher pressure and lower temperature than other fuels.
Process diagram
Reception → separation → combustion → heat recovery → power + flue gas treatment
Reserved for a static waste-to-energy process diagram showing reception, mechanical treatment, micronization, combustion, turbine or gas engine, superheating, steam turbine, flue gas treatment and ash handling.
Static process diagram — final artwork to be supplied.
Detail
The biological route
Anaerobic digestion converts wet organic material into biogas without combustion. It is the right answer for sewage sludge, food waste, agricultural residues and animal manure — feedstocks with too much moisture to burn economically.
Where the feedstock is a high-strength industrial effluent rather than a solid, the same principle applies inside an anaerobic membrane bioreactor, which treats the wastewater and produces biogas in a single step.
Detail
Heat that is already there
Before building anything new, most industrial sites have recoverable heat leaving the stack. Waste heat recovery, waste heat recovery boilers, heat recovery steam generation and gas flare recovery convert that into steam or power, usually at a much lower capital cost per megawatt than new generation.
Where the recovered steam is at a pressure that would otherwise be throttled, an energy recovery turbine from 3 to 10 MW generates power from the pressure drop instead of wasting it across a valve.
Applications
Applications and challenges
Where it applies
- Municipal solid waste treatment with energy recovery
- Industrial waste with calorific value and no disposal route
- Sewage sludge-to-energy at municipal works
- Food waste and agro-processing residues
- Agricultural waste and animal manure
- Waste heat recovery on existing industrial plant
- Gas flare recovery at oil and gas facilities
- Landfill diversion and circular economy programmes
Common challenges we are asked to solve
- Feedstock variability upsetting combustion and emissions
- Emission limits the existing plant cannot meet
- Moisture content making thermal treatment uneconomic
- Digester underperforming against its design gas yield
- No use on site for the heat that would be recovered
- Financing a project whose feedstock supply is not contracted
FAQ
Frequently asked questions
Thermal or biological — which suits our waste?
Moisture and calorific value decide it. Wet organic material — sludge, food waste, manure, agricultural residues — goes to anaerobic digestion. Drier, calorific and mixed waste goes to thermal treatment with heat recovery. Characterisation comes first in both cases.
What does the waste separation technology do?
It works with both selected and unsorted municipal waste, downstream of mechanical treatment, using a mechanochemical micronization process that alters the molecular structure of the material. That makes it available for combustion and contributes to its stabilisation and sanitation. It can be fixed downstream of shredding or supplied as a mobile unit.
How efficient is the combined cycle configuration?
The configuration uses municipal solid waste as the primary fuel for a turbine or gas engine, then uses the recovered flue gas to superheat steam entering the water turbine — producing combined cycle power or CHP at a higher pressure and lower temperature than other fuels. Actual efficiency depends on the feedstock and the site, and we would model it rather than quote a generic figure.
Is waste heat recovery cheaper than new generation?
Usually, per megawatt. The heat is already being produced and paid for; recovering it needs a heat exchanger, a boiler or a turbine rather than a new fuel supply. It is the first thing we look at on an existing site.
Evidence
Projects
Sample layout. Reference projects are being cleared for publication with the clients concerned. The structure below is final; the content is placeholder.
SampleWater reuse retrofit — sample card
Card layout for a completed water reuse project: stream data before and after, recovery achieved, scope Glorinda held, and the client's own words.
SampleZLD package — sample card
Card layout for a zero liquid discharge package: feed characterisation, evaporator type selected, solid output route, and commissioning duration.
SampleOwner's engineer mandate — sample card
Card layout for an advisory mandate: the client's decision, the options assessed, and what changed in the tender as a result.
Conversion
Take this further
Send us the stream data, the discharge limit or the equipment list you are working from. An engineer reads every enquiry and replies with the questions that actually decide the solution — not a brochure.
Contact
Talk it through with an engineer
Send the constraint you are designing around and we will tell you what is realistic before anyone writes a specification.