Improved composting in deposition compost shed of a pig farm (Introduced to: S Livestock, Chiba Prefecture) - Deodorization and Composting equipment - Miraie

CASE STUDY

Construction example

2021.10.18 EASYJET

Improved composting in deposition compost shed of a pig farm (Introduced to: S Livestock, Chiba Prefecture)

S LivestockChiba Prefecture
Processed Material and AmountPig manure, rice husks
OverviewEasyJet Jr. was used in the deposition compost shed to improve composting, shortening the fermentation period and improving compost quality.

Measures and Effects

Increase processing amountHigh pressure aeration improves aeration, making it possible to do stable processing even in winter.
Raise fermentation temperatureCompared to conventional systems, the fermentation temperature increased by about 10˚ C.
Improve compost qualityAeration eliminates foul odors from compost, reduces moisture content, and improves compost quality.

S Livestock composts manure from fattening pigs in a compost shed. One compost shed has 4 tanks, and each tank is 3 meters wide by 5 meters deep. Compost is deposited 1.6 meters high. Rice husks are mixed with pig manure.

Conventionally, processed materials were turned over and moved to the neighboring tank once per week. However, they were troubled by how much time it takes to do this work (about 30 minutes to move one tank) and the foul odor generated when moving compost. Especially when moving processed materials that have only been deposited for a few days, a large amount of foul odor was generated from inside.

Therefore, S Livestock decided to insert EasyJet Jr. into fresh pig manure immediately after it is discharged, in order to save time spent on moving (turning over) and reduce the odor.

Fermentation temperature rose to over 70˚ C after using EasyJet Jr..

Generally, the fermentation status of compost is checked by checking the fermentation temperature.

Of course, it is important for fermentation temperature to rise, but it is not enough just for the temperature to be high. Even when the temperature is high enough, the interior of processed materials is often anaerobic due to lack of oxygen.

Oxygen concentration in the atmosphere is 21%, but oxygen concentration inside compost material is about 15% immediately after turn over.

However, when there is food (organic matter), oxygen is actively consumed by the actions of microorganisms, steadily decreasing oxygen concentration.

Fermentation rate is proportionate to oxygen concentration, and it is desirable to have an oxygen concentration of 10% to 15%. However, it is said that when oxygen concentration reaches 2% to 6% the reaction rate is cut in half, and when the oxygen concentration falls below a certain level, aerobic reactions stop (Composting Technology, by Kenji Fujita).

When S Livestock actually measured oxygen concentration in tanks where only turn over was done, concentration had dropped below 3% just a few hours after turning over compost.

In contrast, the tank using EasyJet Jr. showed an oxygen concentration of 10% to 15%, so we can see that it is in an aerobic state.

This is the compost when the inside was dug out after leaving EasyJet Jr. inserted for a month and a half.

Even when the compost is dug up, there is no odor, and it is covered with actinomycetes, turning it white. Half of the compost is dried out well, and the moisture content had fallen to 30%.

It can now be used as return compost for moisture adjustment, but might have too little moisture to be shipped as compost.

Based on these results, we plan to devise ways to use it so as to change the insertion position of EasyJet Jr. in about 1 to 2 weeks.

The president of S Livestock praised the system, saying “Fermentation is fast, and doesn’t take much work. Even when digging up the compost, it does not emit a foul odor, so it is easier to take out.

The compost is dry and easy to use.”