Drying highly moist pig manure (moisture content 95%) without auxiliary materials (Introduced to: Pig Farming A Co.) - Deodorization and Composting equipment - Miraie

CASE STUDY

Construction example

2021.10.15 EASYJET

Drying highly moist pig manure (moisture content 95%) without auxiliary materials (Introduced to: Pig Farming A Co.)

PlaceNagasaki Prefecture
Processed Material and Amount10 tons/day, 1,400 sows, solid-liquid separated manure, moisture content of 95%
OverviewPig manure in a slurry state processed at low cost with no auxiliary material costs, by combining high pressure aeration and a rotary stirring device.
Increase processing amount 1High pressure aeration was introduced to the rotary tank, which previously had cooled down in winter, enabling it to do processing year round.
Increase processing amount 2By mixing with an adequate amount of dried return compost, which helped to stabilize processing.
Raise fermentation temperatureBy switching from blowers to high pressure aeration for aeration in initial fermentation, the fermentation temperature was raised significantly.
Reduce costBy stopping the use of wood chips and other auxiliary materials that incur purchase costs, and by using the return system for all material, they reduced costs.
Improve compost qualityThe temperature rises early thanks to the improved aeration, so compost is dry year round (moisture content of 35%), and it is possible to make high quality return compost.

Here we introduce a case of endless treatment of high moisture pig manure, which reduced the cost of auxiliary materials (sawdust).

Here we introduce a case in which 1,400 sows (with a total of 15,000 pigs) are raised in grate floor pigsties. Manure that flows down from the pigsty is separated into solid and liquid matter, but the solid matter still has moisture content of 95%, and 10 tons of it is generated per day (liquid is subjected to wastewater treatment).

5 tons, half of the solid matter, is fermented and dried endlessly using EasyJet and a rotary stirring device.

Layout of the rotary fermentation tank

The specific method of operation is as follows.

On the left is the layout of the rotary fermentation tank. It has an EasyJet embedded in 32 meters of the floor (inside the red box), about 20% of the total length.

High moisture content manure is added to this part every day, from the top of the return compost.

The input high moisture manure has its moisture content reduced to 45% during in one trip around the rotary tank, so high moisture manure can be applied again.

After embedding EasyJet

This method offers two advantages.

(1)No auxiliary materials are used (entirely covered with return compost), so there is no need to purchase auxiliary materials.
(2) Almost no compost removal work is required.

The first advantage greatly contributes to cost reduction, as the price of wood materials has soared in recent years.

Compared to the method of composting in a compost shed, this simple composting method requires 5.6 tons of auxiliary materials per day (approximately 15 m3/day to 20 m3/day) in order to process 10 tons/day of manure that has moisture content of 95%. Assuming that 1 m3 costs ¥800, the purchase cost of auxiliary materials alone would exceed ¥4,000,000 per year.

Also, assuming that the compost is fermented in 90 days, it would be necessary to have a compost shed with an area of more than 1,000 m2.

The photos below compare the section where EasyJet was not used and the section where EasyJet was used, with the same materials and same starting time.

There was a major difference in fermentation temperature, and a clear difference in the dryness.

If the fermentation temperature in the fermentation tank is low, then moisture will not evaporate as much, so in winter the drying efficiency was about 30% lower in the fermentation tank without EasyJet (In other seasons it can process 5 tons of manure per day, but in winter it can only process about 3.5 tons per day. Inputting any more manure will make it unusable as return compost.).

In this case, if they were to add one more unit, the cost of introducing a 400 m2 compost shed and rotary stirring device would exceed ¥10,000,000. If the fermentation temperature does not rise even after increasing the number of units, there would still be the problem of preventing disease among the animals.

With EasyJet, fermentation temperature properly rises, and costs can also be reduced.

Declining manure processing capacity made a great impact on the environment and disease prevention on the farm, so we recommend taking measures soon.

EasyJet can also be installed in existing fermentation facilities, so please contact us for consultation.

Prior to introduction, we conducted laboratory level tests using high moisture content manure as a material, measured and analyzed data, then made a proposal.

Left: Without EasyJet / Right: With EasyJet