JPS5850798B2 - Multi-stage fermenter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-stage fermenter that effectively performs aerobic fermentation treatment of organic waste such as sludge, household garbage, and livestock manure using a low-bulk device. .

When fermenting sludge, household waste, livestock manure, etc., adjust the moisture content by mixing organic matter such as rice husks and sawdust with secondary sludge, etc. so that the moisture content is suitable for aerobic fermentation. This is supplied into a fermentation tank in which an aerobic atmosphere is maintained, and the inside of the fermentation tank is partitioned into a plurality of sections at approximately equal intervals in the vertical direction,
The desired aerobic fermentation is carried out while sequentially transferring from the upper stage to the lower stage.

However, the fermentation activity of the fermented material such as sludge differs between the primary fermentation and the subsequent secondary fermentation, and its volume also decreases over time.

Therefore, in the secondary fermentation process, if the partition height of each stage is the same as in the primary fermentation process, there will be more space than necessary above the reduced bulk of the fermented material, which makes the fermenter height unnecessary. This increases the production cost.

The present invention has been made in view of this, and will be described below based on Examples.

In the figure, 1 is a multi-stage fermenter body that supplies fermented materials such as sludge whose moisture content and air permeability have been adjusted in advance to suit aerobic fermentation. Step bed 2
A large number of tiers are provided, the tiers are multistage, and each tier is opened and closed simultaneously or selectively (opening/closing of tiers by sliding, swinging, rotating, etc.), and the tiers are supplied to the top tier of the main body 1. The material to be fermented is transferred to the lower tier (falling transfer) while being sequentially turned over at intervals of a certain number of days suitable for promoting aerobic fermentation, and during this process, air is supplied to the material to be fermented in each tier to achieve the desired fermentation. It is something that allows you to do the following.

The volume change over time during the aerobic fermentation process of this fermented material is as shown in FIG.

Focusing on this point, when each stage bed of the fermenter is provided, the interval between the stage beds is determined in such a way that there is always an effective space necessary for aerobic fermentation in accordance with the change in reduced volume.

To explain the fermentation tank shown in Figure 1, the volume of the fermented material in each stage is increased by increasing the volume of the fermented material in the upper stage■1. ■ 2 to v8, suitable for aerobic fermentation with air supply and exhaust, and a device for dropping fermented materials to the lower tier side (opening/closing the tiered floor), when fermented materials are loaded on each tier bed. Let Vo be the space above the object.

This space Vo is the same for each stage.

Furthermore, if the number of fermentation days on each stage bed is 3 days, then from Fig. 2, v2f-0,88V1 0.82V1 in v3 0.78V1 in v4 v5f-0,75v1 V6=:=0.73V1 *■7 in 0.72V1 V==0.71V1, and it is clear that the volume on the lower side decreases over time compared to the volume on the upper side depending on the fermentation process.

And the volume reduction ratio during primary fermentation is much higher than that during secondary fermentation process.

Further, if the floor area of each stage of the fermenter is S, the total stowage height H is as follows.

becomes.

Therefore, if we consider the volume reduction (due to fermentation over time) to determine the effective height of each bed, then the total height of the fermenter is 1.61V1 - The fermenter volume is 1.61V
1, and aerobic fermentation can be carried out as efficiently as in conventional fermenters.

The fermenter is equipped with a supply device at the top and a take-out device at the bottom.

According to the present invention, the effective height of each stage of the fermentation tank is determined by taking into account that the volume decreases as fermentation progresses over time, thereby achieving the same processing capacity. There are advantages in that the size of the fermenter can be reduced, the cost of the fermenter can be reduced, and the cost of fermentation processing can be reduced.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a multistage fermenter according to the present invention, and FIG. 2 is a graph diagram showing changes in volume of fermented materials over time. 1... Fermentation tank body, 2... Tier bed, ■1
~V8...Volume of fermented material, Vo...
The space above the fermented material on each stage.

Claims (1)

[Claims] 1. In a vertical multi-stage fermenter in which a plurality of fermentation chambers are partitioned by a plurality of vertically openable and closable tiered beds, and the fermentation chamber is allowed to fall and transfer from the upper tier to the lower tier in a constant cycle. , the height between each tier bed is gradually lowered from the upper tier side to the lower tier side according to the volume change caused by the progress of fermentation of the fermented material (and the volume of each tier bed is determined to be an effective volume). A multi-stage fermenter characterized by: