Process
Kitchen waste is unloaded into receiving hopper from transportation vehicle, and then transferred to bag-breaking drum screen after leached. After being broken and screened, screen residue are mainly high calorific value materials such as plastic and paper, which are directly transported out for incineration. Undersize material is mainly organic matter and small number of sundries. After sorting, magnetic separation, removal of large objects and metals, it is sent to biological hydrolysis reactor. Through mechanical, biological and hydraulic interaction, biodegradable organic matter is hydrolyzed and dissolved into liquid phase, organic slurry and high calorific value solid phase separation are realized by extrusion dehydration. The organic slurry is sent to the anaerobic system after sand removal. Solid residue separated from solid and liquid has low moisture content, high calorific value and is transported out for incineration.
Biogas is produced by anaerobic system fermentation. After purification, it can be directly used for resource utilization, such as for boiler, power generation or purification. Some of the biogas liquid produced by the anaerobic system is returned to biological hydrolysis system as leached liquid, and the rest enters wastewater treatment unit and discharge after reaching standard. Biogas residue of anaerobic system and sludge of wastewater treatment system are dehydrated and transported out for harmless treatment.
After above-mentioned treatment, kitchen waste is finally reduced, harmless and resourceful.
Advantages
High adaptability of waste with different classification efficiency:
Only mature and stable drum screen and magnetic separation unit is needed. Hydrolysis reactor with simple structure has strong material adaptability.
The anaerobic reaction unit is mature, reliable and stable:
The EMBT process put the hydrolysis acidification stage into the biological hydrolysis reactor, and assisted by the mechanical and hydraulic functions, strengthened biological hydrolysis process. After the hydrolysis, material with COD of about 60000-80000mg/L enters the methane production reactor to produce biogas. The technology is reliable, stable, simple to operate, and organic matter degradation rate is more than 80%.
Compared with other processes, this process is simple, with significant advantages in secondary pollution control and cost:
In process of dry-digestion anaerobic treatment, lots of biogas residue will inevitably be produced. Pollution control, investment and operation cost must be considered, and a large amount of odor will be generated to be treated.
EMBT process is short, and direct products are combustibles with average moisture content of about 55% (sieves and biological hydrolytic dehydration products) and average low calorific value of 2200-2400kcal/kg, which can be directly sent to incineration power plant. Considering pollution control process, investment and operation cost is low.
The process has been in mature and stable operation in Germany for 12 years, pollution control measures are comprehensive, and whole process of treatment is designed and operated in a sealed way. All equipment are pumped for negative pressure operation after sealing, so as to ensure a good working place and surrounding environment.
High level of resource utilization and improvement of economic benefits:
Sorted organic matter enter anaerobic treatment unit, low calorific value of waste after biological hydrolysis is increased from 200 kcal/kg to over 1200 kcal/kg. The average calorific value can reach 2200-2400 kcal/kg after mixed with high calorific value screen residur, which can increase power generation capacity of waste incineration and improve economic benefit. At the same time, organic matter can produce biogas anaerobic, and biogas methane content is 60-65%. EMBT technology can maximize energy use with high efficiency.
