JPS6010071B2 - Coal/water slurry pH adjustment method - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for preparing feed for coal-water slurry.

Coal is attracting attention as an alternative energy source to oil, and the number of coal-based boilers is increasing.

Coal transportation methods include bulk transportation and slurry transportation, but bulk transportation is increasingly focused on slurry transportation for reasons such as environmental protection and the need for an unloader quay. As a slurry transport method, a method of transporting a slurry of heavy oil and coal is carried out using a fuel form of burning heavy oil and coal. However, heavy oil is used in large amounts, resulting in high costs, and since heavy oil and coal are produced in different regions, there are problems such as the need to transport heavy oil to the coal producing region. Therefore, as a method of transporting coal, a method of transporting it as a coal-water slurry and burning it directly in a boiler is being considered. Coal/water slurry is
Although the energy efficiency of the coal itself decreases because it is burned directly in a boiler, it is estimated that it is sufficiently profitable when transportation costs are taken into account. The coal/water slurry transportation method is attracting attention as described above, but when coal is pulverized and made into a water slurry, the slurry fence becomes weakly acidic, so care must be taken to prevent pipeline corrosion. It won't happen. The present invention has been made in view of the above, and its purpose is to prevent corrosion of pipelines when transporting coal as a water slurry.

That is, the feature of the present invention is that in order to adjust the pH of a coal/water slurry, combustion ash of coal or the like is mixed with water, and the alkalinity of the ash content neutralizes the acidity.

The details of the present invention will be explained by the following examples.

Example 1 Blairsall charcoal was pulverized to 45 or less, and 10
20 minutes of finely ground Preasol was added to 0 cc of water, mixed, and the pH of the coal/water slurry was measured at a temperature of 25 to 0, showing weak acidity of 4 to 4.5.

In addition, Pleiasol charcoal is added at 850q0 in an oxygen atmosphere for about 3
The ash was incinerated for 15 hours, and the ash content was put into 100 cc of water. After mixing and ashing, the filtered liquid was added with the above-mentioned pulverized coal to form a slurry, and its pH was determined to be 7 to 7.
．． A coal/water slurry of approximately neutral region No. 3 was obtained. Example 2 Jarun lignite was wet-pulverized to less than 45 mm, and the pH of the coal/water slurry was determined to be 3.7 to 4.2.

By adding the aqueous slurry solution of the incinerated ash of Example 1, the pH of the water slurry of Jaroun lignite could be adjusted to a neutral range. According to the present invention, it is possible to adjust the pH of coal/water slurry to a neutral range using organic combustion ash such as coal without adding expensive alkaline chemicals. This makes it possible to easily and reliably prevent corrosion of lines (lines).

Claims (1)

[Claims] 1. Mix and stir organic combustion ash and water, and separate the water, which has changed into an alkaline state due to the ash, from the ash,
This separated water is then added to the pulverized coal to form a slurry of the coal, and the P of this coal/water slurry is
A method for adjusting the pH of a coal/water slurry, which comprises adjusting the H value to a neutral range using this alkaline water.