Employer/ Beneficiary: Sofiyska voda AD
Implementation period: 08/2018 – 11/2018

Design parameters:

• Two existing sludge post-thickeners with (each of them with D = 40 m, H = 4,5 m, V = 5 000 m³), which are reconstructed and transformed into sludge silos with complete homogenization, according to the technical assignment;
• Anaerobic stabilized sludge parameters:
  – Suspended solids 4÷7 %;
  – Organic compounds 50 %;
  – High fibrous content;
  – Residual biogas content.

Performed activities:

• Survey of the existing situation and construction assessment of the existing reinforced concrete tanks;
• Analysis of known methods for homogenization of stabilized sludge in accordance with best known practices and on the basis of parameters of stabilized sludge and on-site conditions – 7 options developed;
• Options screening and selection of 5 basic options for more detailed evaluation, with data from different manufacturers;
• Homogenization power analysis;
• Analysis of the geometry of the tank and the optimal location of the intended equipment.
• Presentation of the proposed design solutions and model studies;
• Conceptual design of 2 of the selected options in all parts of the project;
• Options comparison and recommendation for the choice of the final version;