JPS5989921A - Sludge feeding method in sludge incinerator system with drying machine - Google Patents

Abstract

PURPOSE:To enable to feed sludge under the moisture content limitation for self- burning even though the moisture content of the dry sludge is made less than 60% by a method wherein a feeding line of a dehydratd cake is divided into two lines formed of a main line and a by-pass line. CONSTITUTION:When the low level heating value of solid content of a sludge dehydrated cake is, for instance, 4,070kcal/kg, and the sludge is incinerated with a system which possible to treat the sludge having a 80% moisture content under the 1,000kg/h incinerating operation, the 260kg/h dry sludge having 50% moisture content can be obtained with a main line which is fed with the dehydrated cake having 80% moisrure content by the rate of 650kg/h. On the other hand, the dehydrated cake having 80% moisture content is fed into a by-pass line without treating, then said dehydrated cake is mixed with the dry sludge at the front stage of a incinerator, after obtaining of the sludge having 67% moisture content at self-burning limitation, the sludge is fed into the incinerator, subsequently, incinerated. Thereby, even though the moisture content of the dry sludge is more than 60% at the outlet of a drying machine, the self-burning in the incinerator can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a sludge supply method in a sludge incinerator system with a dryer, which was previously proposed by the applicant in Japanese Patent Application No. 56-4960 and Japanese Patent Application No. 57-116867. The purpose of this is to efficiently operate the drying equipment within an appropriate operating range for various types of sludge with different calorific values and moisture content, and to send the sludge to the incinerator with a predetermined moisture content that allows for self-combustion. As a result, the problem of discharging dried sludge with a water content of 60 to 80%, which is difficult to handle, at the outlet of the drying device can be eliminated.

Figure 1 shows an example of a sludge incinerator system with a dryer that the present applicant disclosed in the above proposal. In the incinerator to which it is sent, it is dried until it has a moisture content that can self-combust, and then sent to the incinerator, where it is incinerated.

However, in general, sludge with a water content of 60 to 80% has a high viscosity, so crosslinking etc. occur at the dryer outlet.
There were various problems with rebundling.

The inventors performed subsequent tests 1tK,l:! Solid content of sludge If the sludge has a high lower calorific value, the water content of the dried sludge at the outlet of the dryer is 60% as shown in Table 1 below.
It was discovered that even with the above, it is possible to self-combust in an incinerator.

Table 1 The present invention has been made based on the above findings.
As shown in Figure 6, in addition to the main line of the conventional system in which the dehydrated sludge cake passes through a dryer and becomes dried sludge, a bypass line is installed in which the dehydrated cake does not pass through the dryer, and the water content is reduced from the main line. In addition to supplying dry sludge,
The dehydrated cake with a high moisture content is supplied from a separate bypass line, and the sludge sent from both lines is mixed before the incinerator, so that the mixed sludge has a moisture content within the self-flammability limit shown in the table above. This is a method for supplying sludge in a sludge incinerator system with a dryer, characterized in that the sludge is fed to the incinerator in the following manner.

Next, to explain in detail the sludge supply method of the present invention, in the case of sludge with a high lower calorific value (per solid content), where the self-combustion limit water content is 60% or more, in the conventional method, the water content of the dried sludge at the dryer outlet is However, in the present invention, by dividing the dewatered cake supply line into two systems, the main line and the bypass line, the water content of the dried sludge at the dryer outlet can be separated from the non-dried cake. Even if the content is 60% or less, which is not harmful, by mixing the two in the front stage of the incinerator, it is possible to supply the incinerator with a predetermined self-combustion limit moisture content as shown in Table 1 above. .

An embodiment of the sludge supply method of the present invention is shown in FIG.

The lower calorific value of the solid content of the sludge dewatering cake is 4070 Kad.
1000 ml of sludge with 80% water content.
When processing in a system that incinerates at a rate of 9/h, this line processes dehydrated cake with 80% moisture at 650
By supplying g/h, dry sludge with a moisture content of 50%26
0 K9/h was obtained, while the above moisture 8 was added to the bypass line.
The 0% dehydrated cake was supplied as it was and mixed with the previously dried sludge in the front stage of the incinerator to form sludge with a moisture limit of υ 67 cm, which was then sent to the incinerator and incinerated.1. There were no adverse effects of the conventional method at the outlet of the dryer, and the incineration process in the incinerator was completed.

[Brief explanation of drawings]

Figure 1 is a process diagram of a sludge incinerator system with a dryer, Figure 2 is a process diagram of a conventional sludge supply method, and Figure 6 is a process diagram of a sludge supply method of the present invention. Agent: Mitsuro Kimura, Patent Attorney 4. Muneharu Sasaki

Claims (1)

[Claims] In a sludge incineration system that combines a drying device and an incinerator, there are two supply lines for the sludge dehydrated cake to be supplied to the incinerator: a main line that passes through the drying device and a bypass line that does not pass through the drying device. A dryer characterized by supplying dried sludge with a low moisture content and supplying a dehydrated cake with a high moisture content from a bypass line, and adjusting the moisture content to a predetermined level by mixing both in the front stage of an incinerator. Sludge supply method in a sludge incinerator system.