Colsen offers services in different branches. In all those branches we are active in consultancy, project realisation and research & development.

Read more about Colsen as a partner here.

9 services
Slibgisting Tiel

Sludge to energy

Sewage sludge is produced during the wastewater treatment process, and processing and disposing of said sludge is a major money and energy sink.

Amfer leidingen


In certain waste and wastewater flows, high quantities of nitrogen occur in the form of ammonium, such as in digestate or centrate produced by a di

Pizzoli NAS

Nitrogen removal

Many sectors produce highly polluted wastewater, with nitrogen being one of the main pollutants. Removing nitrogen can be very expense.

Biogasinstallatie BIDOX

Biogas desulphurisation

Untreated biogas can cause serious, or even permanent damage to systems such as boilers, cogeneration systems or biogas upgrading systems, which co

PEKA Kroef

P-recovery with struvite

Phosphate is a crucial component of artificial fertilisers, but the main mining areas are slowly becoming depleted, which makes phosphate recovery

UASB Kroef

Anaerobic water treatment

Due to the high levels of organic pollutants in wastewater, wastewater treatment can be an energy-intensive and therefore a costly affair.

Digestaatbehandeling Navia

Digestate treatment

After the digestion of manure and agricultural products, a residual fraction remains, called digestate.


Chicken manure treatment

There’s a range of known complications when it comes to digesting chicken manure, from overly dry manure, grit contamination to excess nitrogen lev

Mestvergisting Navia

Manure treatment

Whether the aim is drainable water, maximum phosphate removal or nitrogen recovery for fertilisers; manure digestion is always the first step.