Hokudo Kaihatsu: “Reliable composting in an area with -30˚ C weather”￼
Can sludge be processed better with its own power?
Originally, we had introduced mechanical drying machinery for treating sludge, and sold dry fertilizer.
However, dry fertilizer was dusty and difficult to handle, and nutrients were not spread evenly. We’re not really doing recycling if we’re able to process something but not able to sell it. I really felt that strongly.
What’s more, the machinery was showing its age, heavy oil prices and cost soared for fuel which exceeded 10 tons per month, and the amount we had to process increased year on year. Due to these and other issues, we had no choice but to establish a new processing method.
Focusing on compost treatment of sludge, I began to wonder “If we ferment sludge using its own power, can we process it without fuel?”
With the hope of making compost that returns as much as possible to farms in the community, we started three years of trial and error.
Our greatest challenge was the cold. How reliably can we make compost during the cold season?
Every day we brought sludge to the composting test facility, in search of the best method for composting.
In Tokachi, it starts to get cold in October and reaches -30˚ C in winter.
When the temperature got that low, it became extremely difficult to raise the fermentation temperature.
Sludge solidified with a flocculant does not mix evenly, even when we tried to mix it with the loader, so air could not get inside.
Our composting tests resulted in a series of failures, as sometimes lumps of sludge would form and fermentation temperature did not rise, or there would be mold and foul odors.
That was when I found Miraie.
Based on issues that had arisen in tests we have done so far, I looked for equipment that can reliably ferment compost even in winter.
I also felt that we needed a mixer in order to efficiently mix 30 to 40 tons of sludge and auxiliary materials per day.
It was then that I saw the Miraie website, and decided to take a tour of a place where C-MODE (a mixer) and EasyJet are installed.
The facility I toured processes a huge volume of compost with few workers. After seeing installed equipment with my own eyes, I felt certain that it could solve our problems too.
The deciding factors for choosing C-MODE were the facts that it is a mixer developed specifically for composting and that it has a simple design.
As I discussed composting with Miraie, they gave me all sorts of advice, and we asked them to make a plan for the entire plant.
So I decided to introduce C-MODE and EasyJet.
Can we really do so much composting with so few people?
Now outsiders who come to tour our facility are surprised by what they see.
Even on days when the temperature is low outside, EasyJet smoothly raises the temperature, so we can reliably make compost in 28 days, even in the dead of winter.
Mixing also goes very well, so there is less work with heavy machinery, and we can process compost with few staff.
Also, we do not have to pay the cost of heavy oil, which was a heavy burden. We only have to pay the electricity bill for EasyJet and the fuel bill for heavy equipment, so our processing costs have gone down significantly. Finished compost is used as a fermentation accelerator by livestock farmers, and is also sold in trailers as compost for crop rotation of fields.
“I hope that Miraie will be a bridge for providing information to companies in the same industry, and processing facilities will improve nationwide.”
We also felt that we want to further improve the quality of our products and compost processing technology, so that we can please as many customers as possible.
The smiles on the faces of Mr. Yamada and Mr. Takei show how delicious Hokkaido vegetables are.
One could see from the looks on their faces that they really took joy in being able to return compost to their bountiful land.
About Hokudo Kaihatsu
Hokudo Kaihatsu’s processing facility, Hokudo Recycling Center (LOOP) is located in Memuro Town, Hokkaido Prefecture. In winter, which lasts for half the year in this area, this facility composts 7,000 to 8,000 tons of dehydrated sludge that is discharged annually from sugar factories (Nippon Beet Sugar Manufacturing).
The facility was built to recycle the by-products of the sugar-making process, which used to be discarded in landfills, thereby contributing to the recycling of the huge volume of biomass generated in the area.