Wastewater is valuable
In several regions in Europe, waste water is recycled with renewable energy as a result.
This is done by using innovative concepts for (alternative) water supply, wastewater treatment and recovery of resources.
Surplus on Energy
By centralizing the sludge and the thermal pressure hydrolysis a single wastewater plant is able to produce a ‘surplus’ of energy, which corresponds to the energy consumption of approximately 3,000 households. Annually! This purification produces biogas, which can be converted into electricity and heat.
By optimizing the sludge fermentation process, combined with a number of adjustments to the treatment process, energy consumption can be reduced even further and the amount of energy can be increased.
Since 2010 there is a surplus of energy that is good for the electricity needs of 1,300 households. Also is already hot water delivered to hundreds of new homes nearby. Since December 2014, the biogas which is released and converted to electricity supplies in the electricity needs of 3,000 households.
The industry will also produce 900 tons of fertilizer.
The sludge from three sewage treatment plants in the South of the Netherlands is sieved, mechanically concentrated hydrolyzed, fermented and dehydrated. From in total 7,000 tons of dry matter, the biogas is converted into heat and electricity.
The sludge released in the Beverwijk sewage plant is treated in a digester and produces biogas. This biogas consists largely amounts of methane gas. And methane gas is the main component of natural gas. In a green gas processing plant this biogas is converted into green natural gas and pure CO2.
- A part of the green gas is used for cars
- The rest of the gas is pumped into the public gas.
- The pure CO2 is a valuable by-product that can be sold.
Interesting customers are greenhouses companies, food industry and cold stores.
Iron sludge from drinking water in The Netherlands. In this case a value chain is developed that produces granular iron hydroxide that can be used as a filter material for e.g. biogas purification (H2S removal).
Phosphorus from wastewater in Belgium, Germany, Switzerland and The Netherlands. Several routes for P-recovery are being explored as well as ways to produce high value fertilizers from these resources.
Cellulose from wastewater in France, Germany and The Netherlands. Cellulose will be harvested at full scale at wastewater treatment plants. Value chains will be developed for cellulose as resource for e.g. building blocks for bioplastics.