Q2 What are the features of KOBELCO ECO-SOLUTIONS’system?

Our system has the following features.

1. Our system doesn’t have a sludge drying process. Therefore, it is free from odor issues associated with sludge drying equipment, as sludge tends to diffuse smell more when heated than raw sludge does.
   (Odor free)
2. The incineration process and melting process can be operated separately. Therefore, even if the melting furnace is interrupted due to trouble or maintenance, our system can continue to incinerate sewage sludge without melting.
   (Flexibility of operation)
   We can also modify an existing incineration facility into an incineration-melting facility comparatively easily. Some customers plan to equip only an incineration facility at first and then add a melting facility in the future. In this case we can design according to the customer’s needs.
   (Flexibility of expansion)
3. We adopt a vertical type melting furnace. In Japan other companies which construct melting facilities adopt a slope type. Compared with a slope type, it needs less space for installation and has a longer- refractory life due to a shorter slag retention time.
   (Space saving and Long life)
4. In case of the direct melting system, the system shall be controlled simultaneously while considering three correlated factors (sludge moisture, calories, and ash properties). However, with our ash melting, we only consider two simultaneous factors along with one separate factor. This means we can control the system by considering sludge moisture and calories at the incinerator and ash properties at the melting furnace. So the system is easily operated.
   (Easy operation)
5. An ash melting type melting furnace is approximately one-third smaller than a direct melting type with the same sewage sludge capacity.
   A melting furnace’s refractory generally needs to be repaired more than twice a year. In this regard, the ash melting type is less costly than the direct melting type.
   (Cost saving)
6. Generally speaking, it is said that melting furnaces still suffer from low reliablity and availability. However, our melting furnace enjoys high availability thanks to unique ash preparation know-how.
   For example, the Konan facilities of our track records in Japan are available more than 80% of the time.
   (High Availability)
   

   Availability (%) =melting hours/calendar hours*100

   Generally refractory maintenance of a melting furnace is needed twice a year. So, annual operating is approximately 330 days.
7. It is said that blowholes sometimes occur inside slag during direct melting. However with the ash melting type, we can constantly achieve a stable operation as the effect of sludge property fluctuations such as the moisture rate and calories are distinguished at the incinerator, and as we can concentrate solely on melting at the melting furnace. Therefore, the ash melting type can produce more uniform and higher quality slag than the direct melting type.
   (Stable operation and high quality slag)
8. Heavy metal is trapped and stabilized inside the slag. Therefore there is no leaching problem.
   (No leaching from slag)