Wastewater treatment plants
Sludge processed right where it arises.
More
A mobile line pays off from just a few hundred tonnes of sludge a year (e.g. 300 t). The product can be contracted in advance by local farmers.
FuelCal® technology · Evergreen Solutions
Organic waste and animal by-products don’t have to be just a cost
A technology for managing waste and production biomass, including animal by-products, at the point where they arise.
FuelCal® lets you feed properly prepared production streams into the manufacture of marketable products: fertilisers and soil conditioners from the OrCal® family.
- 1 300 000 t+of waste processed into OrCal® productsand growing
- dozensof FuelCal® installations operating in Polandstationary and mobile units, plants accepting waste from third parties, and installations extending an existing production line
- up to 1000 t/dayat a single plantin a suitably selected industrial configuration
- from 150 kg/hscale matched to the plant’s needsfrom 150 kg/h to approx. 45.5 t/h of processed substrate (waste, thickened digestate, ABP) (1000 t/day at 22 h of operation)
The challenge
Waste that weighs on your plant’s financial and environmental performance
- Rising costs of managing waste, digestate, animal by-products and agri-food biomass
- Storing waste on site
- Waste transport and logistics
- Demanding environmental requirements
- Financial and legal liability for waste
The solution
Management at the point of origin of waste, animal by-products, digestate, poultry manure, biomass and plant-based food waste, resulting in a product with commercial value
FuelCal® is a technology distributed by Evergreen Solutions of Pyrzyce, Poland. It turns the problem of managing waste and production biomass into a process that makes a product with commercial value. Depending on the plant’s model, this means lower costs, the option of charging gate fees for accepting waste, and revenue from selling the finished product.
- Organic waste
- Agri-food and production biomass
- Animal by-products (ABP: poultry manure, manure, milk, colostrum, digestive tract contents, feathers, blood, bones, etc.)
- Sewage sludge from municipal and industrial wastewater treatment plants
- Digestate
- Evergreen Solutionstechnology supplier and implementation partner
- FuelCal®processing technology
- WapCal®reagent used in the FuelCal® technology
- OrCal®family of end products: fertilisers and soil conditioners
How FuelCal® works
From waste to fertiliser in four steps
- Problem
Waste arises, and with it the cost of managing it
A waste producer generates waste, digestate, production biomass or ABP. This brings costs of storage, transport and handing over to third parties for management, and this stream often weighs on the producer’s financial and environmental performance.
Integrating FuelCal® into the production process can make it possible to manage this material on site and to reduce or eliminate the need to send it off site as waste, depending on the solution used and the product status obtained.
- Solution
Processing in FuelCal®
A suitably selected configuration prepares and homogenises the substrate, then puts it through a controlled reaction and sanitisation process in FuelCal® reactors.
The installation can handle the plant’s own streams or accept suitable materials from other producers. Waste heat can also be used, e.g. from cogeneration.
- Product
OrCal® is created
A fertiliser or soil conditioner from the OrCal® family, a brand well known on the Polish agricultural market and increasingly recognised worldwide.
Selling the finished product creates an opportunity for additional revenue.
- Success
The product reaches the customer
It goes to farms and to wholesale and retail outlets through the distribution network, or is sold directly from the plant.
Three ways to improve your results
- Lower costsreduced costs of managing your own waste, ABP, digestate and other biological substances
- Gate feesthe option of charging other producers for accepting waste, ABP, digestate and other biological substances
- Product revenuesales of OrCal® fertilisers and soil conditioners
The share of each source depends on the plant’s business model.
Video
See the FuelCal® line at work
The footage shows sewage sludge being processed into OrCal® on a FuelCal® production line. The installation in this video is equipped with a catering waste (HoReCa) shredder.
Production process
Feedstock (waste) preparation for FuelCal® depends on the substrate
Dewatering and shredding can take place separately or together, depending on the properties of the material. All paths converge at the homogenisation stage.
High-water-content materialsIndustrial and municipal sewage sludge, blood, digestate
DewateringPress or centrifuge
IntakeBuffer tankat a wastewater treatment plant, material arrives directly from the press or centrifuge
Materials requiring shreddingABP (bones, intestines, feet, horns, etc.), other agro-industrial biomass (e.g. grass, haulm, etc.)
IntakeSkipsmaterials delivered from outside; standard 5–45 m³, up to 75 m³ to order
ShreddingShredderselected for the type of material and the required capacity
Materials requiring both stagesWet and heterogeneous streams
DewateringPress or centrifuge
ShreddingShredder
Recipe componentsMicro- and macronutrients, tested ashes
DosingProduct enrichment according to the recipesuitably selected and tested ashes as a possible process component
Common stageHomogenisation
The prepared streams enter a buffer tank, where the mass is homogenised.
- Reaction and sanitisationin an RCal reactor with WapCal® reagent. Heat comes from the exothermic reaction, with no external supply needed in the basic variant.
- Discharge and maturinga belt conveyor takes the product to the storage area, where it matures.
- Preparation for salesold in bulk or further shredded, packaged and filled into big bags.
Process details
- Preparation and dewatering – industrial and municipal sewage sludge, blood, digestate and other high-water-content materials may need dewatering in a press or centrifuge. The required dry matter content depends on the substrate and is 13–30% DM (22% recommended).
- Intake – at a wastewater treatment plant, material can go directly from the press or centrifuge to the buffer tank. Materials delivered from outside are received in skips with a standard capacity of 5–45 m³ (up to 75 m³ to special order).
- Shredding – for materials that require it, including ABP (bones, intestines, feet, horns, etc.) and other agro-industrial biomass (e.g. grass, haulm, etc.). We select the equipment for the type of material and the required capacity.
- Homogenisation – the mass is homogenised in the buffer tank. Depending on the recipe, components can be dosed to enrich the product with micro- and macronutrients, including suitably selected and tested ashes and other valuable wastes containing ingredients that increase the fertiliser value and the economics of the project.
- Reaction and sanitisation – in an RCal reactor with WapCal® reagent. Heat comes from the exothermic reaction, with no need for external supply in the basic process variant. Heat from other processes, e.g. cogeneration, can also be used, which lowers production costs.
- Discharge and maturing – the product is carried by belt conveyor to the storage area, where it matures.
- Preparation for sale – sold in bulk or further shredded, packaged and filled into big bags.
Use of heat
- Waste heat from cogenerationwaste heat from cogeneration systems can be used, lowering production costs
- Process heat recoveryprocess heat can be used to heat the hall or for other production processes
These are optional solutions: they depend on the installation’s configuration, the availability of heat sources and the heat balance of the whole system.
Benefits
What your plant gains
Economics
- Lower transport costs
- Lower costs of external waste management
- The option of avoiding fees for handing over your own waste
- The option of earning revenue by accepting suitable waste, agri-food biomass and ABP from other producers
- Revenue from selling OrCal® products
- Use of the product on your own farm or barter settlements with farmers
- Lower infrastructure outlays with a containerised or mobile solution
Environment
- Material managed where it arises
- Less waste transport
- Use of heat from the exothermic reaction
- Reduced odour nuisance
- UNS1 – condensate neutralisation system integrated with every RCal reactor; it captures the gases and condensate produced in the process
- CUNS – central condensate neutralisation system (scrubber); it cleans process gases extracted from their points of origin
- Sanitisation eliminates pathogens in the product
Formalities and operation
- In Poland, Evergreen Solutions handles the procedure for obtaining a product decision from the Ministry of Agriculture and Rural Development; this is part of our experience and scope of services on the Polish market
- The process in the reactor runs automatically, under human supervision. It is controlled from an operator console or a wireless tablet
- The tablet can stay in the loader cab, so the operator can supervise the installation while feeding in substrate and collecting the product
- Operated by 2 people on the container line and in a single-reactor installation; 6 people in an eight-reactor installation
Environment
CUNS – Central Condensate Neutralisation System
A scrubber (wet washer) that cleans process gases. It is connected to extraction ducts and hoods that collect gases from their specific points of origin: material transfer points and finished product discharge points.
CUNS is not a hall ventilation system and does not replace one. Each RCal reactor also has an integrated UNS1 system.
Automation
Operator console or tablet
The process in the reactor runs automatically, under human supervision. The panel shows the line’s operation and lets you respond to alarms.
Tell us the type and quantity of your substrate and what managing it costs you now. We’ll select a configuration and prepare the economic assumptions.
Send your dataWho it’s for
For organisations with organic waste and biomass streams
Food industry and ABP
Production biomass and animal by-products.
More
Slaughterhouses, poultry and meat plants, dairies, breweries, fruit and vegetable processors, wineries. A mobile line can visit, for example, once a month.
Biogas plants
Digestate processed into a product with further uses, including with heat from cogeneration.
Agriculture
Management of manure, poultry manure and other biomass streams.
More
On pig farms, without building covered lagoons. In crop production, seasonally, e.g. after harvest, with OrCal® going back onto your own fields.
City cleaning and municipal companies
Municipal and state-owned waste management companies with green waste and biomass.
Waste treatment plants and civic amenity sites
Waste treatment and management plants and operators of separate waste collection points.
Which substrates
FuelCal® processes into OrCal®, among others:
The installation and feedstock preparation are selected for the type of substrate. In Poland, processing category 2 ABP requires a decision from the District Veterinary Officer.
- Sewage sludge
- ABP cat. 2 and cat. 3
- Manure
- Digestate
- Catering waste
- Green waste
- Cellulose
- Biomass
- Feathers
- Bones
- Bristles
- Hen manure
- Brewer’s grains
- + suitably selected ashes as a process component
Other directions
Applications beyond agriculture
- Reclamation of degraded and post-industrial land
- Reclamation of post-mining land
- Applications in landfill reclamation
- Potential support for bioremediation of properly surveyed contaminated land
Separate technology variant
OrCal® EN – selected petroleum-derived waste
Processing selected petroleum-derived waste is a separate variant of the technology, unrelated to making fertiliser products for agriculture.
Projects
Working in Polish wastewater treatment plants and waste processing facilities
Wastewater treatment plant
Sierpc
The municipal plant processes sewage sludge in a FuelCal® installation into OrCal® SR pHregulator®, which is then sold.
Project
Koło
A FuelCal® installation processing waste into OrCal®.
Before implementation
Waste stream = cost
- external management fees
- transport and storage
After implementing FuelCal®
Lower costs + product revenue
- material processed on site
- sale of OrCal® or settlements with farmers
Installations
From a mobile line to an industrial installation
FuelCal® is a scalable technology, not a single machine. The equipment is selected for the quantity of waste and the type of substrate.
150 kg/h – approx. 45.5 t/h
Scale matched to the plant’s needs, in processed substrate (waste, thickened digestate, ABP), at an average operating time of 22 h per day. The three configurations below are examples, not a closed offer.
- RCal-120up to 4.7 t/h of substrate (waste, thickened digestate, ABP)
- RCal-120+up to 4.7 t/h of substrate (waste, thickened digestate, ABP), with the option of process additives, e.g. ashes
- RCal-250up to 1.2 t/h of substrate (waste, thickened digestate, ABP)
- RCal-250 Mobileup to 1.2 t/h of substrate (waste, thickened digestate, ABP), in a mobile line
All reactors have adjustable capacity, from 150 kg/h, and an integrated UNS1 condensate neutralisation system.
Swipe the table sideways to see all configurations →
| Example configuration |  |
 |
 |
|---|---|---|---|
| Processing capacity: substrate (waste, thickened digestate, ABP) | |||
| Per hour (adjustable) | from 150 kg/h to 1.2 t/h | from 150 kg/h to 4.7 t/h | up to 37.6 t/h |
| Per day (22 h) | approx. 26.4 t | approx. 103.4 t | approx. 827 t |
| OrCal® product before packaging | |||
| Per hour | approx. 1.29 t | approx. 5.06 t | approx. 40.46 t |
| Per day (22 h) | approx. 28.4 t | approx. 111 t | approx. 890 t |
| Operation and resources | |||
| Operating time per day | 22 h | 22 h | 22 h |
| Staffing | 2 people | 2 people | 6 people |
| Production area | approx. 150 m² | approx. 370 m² | approx. 6000 m² |
| Electricity | |||
| Installed power | approx. 75 kW | approx. 80 kW | approx. 450 kW |
| Estimated energy use | approx. 36.6 kWh/t OrCal® | approx. 10.0 kWh/t OrCal® | approx. 7.0 kWh/t OrCal® |
Processing capacity refers to substrate (waste, thickened digestate, ABP); product quantity is given before packaging, at a yield of 1.076 t of OrCal® from 1 t of processed sludge. Production capacity depends on the type of substrate, its dry matter content and the recipe used. The 22 h operating time per day is an average; the remaining 2 h are for daily maintenance, servicing and operational tasks (at 15 h of operation the container line processes approx. 18 t of substrate per day). Energy use takes into account an equipment simultaneity factor of 0.63.
Mobility and flexibility
- Operates as a mobile unit
- Stationary use in a container housing
- Line can be moved to another location
- One line can serve several sites
- Less need for expensive infrastructure
- Travels on public roads with a standard tractor unit
On the Polish market the mobile version in most cases requires neither a building permit nor an environmental report, provided a reagent silo of up to 30 m³ is used or WapCal® reagent is unloaded from big bags. Legal requirements, including any need for a building permit or environmental procedures, depend on the chosen installation variant, its location and the scope of the investment.
Configure your installation
Stationary installation
Installation in an existing building
A FuelCal® line can fit into the plant’s existing infrastructure, with a WapCal® reagent silo and its own ventilation system.
Modules
Equipment selected for the substrate
Shredders, presses, conveyors and buffer tanks are selected for the type of material and the required capacity.
Partnership model
From installation design to product sales
We transfer the technology together with know-how and our experience of implementing it and commercialising the product. We help prepare the plant’s team and build a sales model suited to the local market.
- 1Concept
Selecting the technology and preparing a concept for the plant’s specific waste streams.
- 2Configuration
Selecting the equipment, hall layout and logistics for substrate intake and product collection.
- 3Implementation
Implementation support, work organisation and operator training.
- 4Product
Product preparation; in Poland we handle the procedure for obtaining a decision from the Ministry of Agriculture and Rural Development.
- 5Marketing
Marketing materials and the recognised OrCal® brand.
- 6Sales
Sales training, sales support and the platform gielda-nawozowa.pl.
Evergreen Solutions
Experience across the whole implementation process
Our experience covers selecting the technology, configuring the equipment, organising the work, preparing the product and supporting its market launch.
Polish projects and the working OrCal® sales model are a proven base that we pass on to partners: we train operators and sales teams, prepare materials and help organise sales.
End product
The process delivers a product with a real use
An organic-mineral fertiliser with triple action: it deacidifies, enriches and feeds the soil in a single application. Made exclusively with the patented FuelCal® technology. It is the only product on the market combining active calcium hydrate with organic matter. Used by thousands of farmers and winning awards since 2014.
- Deacidifies soil quickly and safely, by as much as 1 pH point in three months
- Enriches the soil, improves its structure, raises its humus level
- Supplies natural macro- and micronutrients, including N, P, K
- Strengthens plant resistance to drought and frost
- Limits the action of harmful soil pathogens
- Eliminates heavy metals in the soil
Evergreen Solutions implementation partnerFuelCal® technologyWapCal® reagentOrCal® products
Forbes Diamonds 2026Evergreen Solutions in the Forbes rankingInstitutional opinions
Contact
Let’s talk about the waste at your plant
Tell us the type and quantity of your substrate and what managing it costs you now. We’ll select a configuration and prepare the economic assumptions.
FuelCal® technology information+48 786 808 474
Helpline+48 880 880 053