JPH0225954B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an additive for water slurry charcoal, particularly an additive for water slurry charcoal that can increase the coal content. In recent years, coal as a fuel has begun to be reconsidered in order to conserve oil resources. However, since coal is solid, it is inconvenient to handle, and there are major restrictions, especially in terms of transportation. As a solution to this problem, a proposal has been made to slurry coal powder in water (referred to herein as water slurry coal) and transport it through a pipe. Since this water slurry charcoal is primarily used as a fuel after being transported, it is desirable to have as little water content as possible, high fluidity, and excellent dispersion stability so as not to impair energy efficiency. The present invention meets the above requirements and provides an additive for obtaining water slurry charcoal with excellent fluidity and extremely good stability using a small amount of water. That is, the present invention provides (a) a nonionic surfactant in which 10 moles or more of alkylene oxide consisting of 95 to 40 mol% of ethylene oxide and 5 to 60 mol% of propylene oxide is added to a compound having one active hydrogen; and (b) ) An additive for water slurry carbon containing a naphthalene sulfonic acid formalin condensate and/or a salt of an alkylnaphthalene sulfonic acid formalin condensate. The nonionic surfactant used in the present invention is ethylene oxide 95 to 40 mol%, preferably 90 to 60 mol%
and propylene oxide 5-60 mol%, preferably
At least 10 moles, preferably 50 to 500 moles, of alkylene oxide consisting of 10 to 40 mol% are added to a compound having one active hydrogen, and the molecular weight of the nonionic surfactant is 1000 to 50000, preferably
2000-30000. The active hydrogen-containing compounds include alcohols and phenols having one active hydrogen in the molecule;
Examples include addition polymers of carboxylic acids and their derivatives with alkylene oxide. Alcohols include monohydric alcohols, such as lower alcohols such as methanol, ethanol, and isopropanol, higher alcohols such as lauryl alcohol, stearyl alcohol, and oleyl alcohol, alcohols with ring residues such as cyclohexanol, abietic acid, and 2-ethylhexanol. Alcohols having side chains such as the following are exemplified. Phenols include phenol, cresol, alkylphenol, phenylphenol,
Examples include styrenated phenol, cumylphenol, and naphthol. Examples of carboxylic acids include acetic acid, lauric acid, oleic acid, linoleic acid, ricinoleic acid, and phenyl acetic acid. The nonionic surfactant used in the present invention includes the above active hydrogen-containing compound, 95 to 40 mol% of ethylene oxide, preferably 80 to 60 mol%, and 5 to 60 mol% of propylene oxide, preferably 20 to 40 mol%. It is obtained by adding 0 or more moles of alkylene oxide consisting of This type of alkylene oxide is preferably a block or random copolymer of ethylene oxide and propylene oxide, preferably a block copolymer with a molecular weight of 1,000 or more, particularly one with a molecular weight of 2,000 to 50,000 and an HLB of 10 to 16. In this case, when the hydrophobic group of the active hydrogen-containing compound is large, a single adduct with ethylene oxide, for example,
Adducts of lanolin alcohol or nonylphenol with ethylene oxide are preferred. The formalin condensation degree of the naphthalene sulfonic acid formalin condensate or the alkylnaphthalene sulfonic acid formalin condensate used in the present invention is about 2 to
10, preferably 2 to 5, and the salt is an alkali metal, alkaline earth metal, ammonia, amine, alkanolamine, etc., with sodium, potassium, and ammonia being particularly preferred. The alkyl group of the alkylnaphthalene sulfonic acid has 1 to 8 carbon atoms, preferably 1 to 4 carbon atoms. The weight ratio of the nonionic surfactant to the salt of naphthalene or alkylnaphthalene sulfonic acid formalin condensate is preferably from 50/50 to 95/5, particularly from 60/40 to
80/20 is preferred. The water slurry charcoal additive according to the invention may further contain other components, such as protective colloids such as CMC, methylcellulose, hydroxymethylcellulose, polyacrylates, flow modifiers, etc. The amount of water slurry coal additive used according to the present invention varies depending on the particle size of the coal, but
% pass pulverized coal, 1% by weight or less based on the coal powder is sufficient, and it is preferable to increase the amount as the particle size of the coal powder becomes smaller. Usually used at 0.1-1.0% by weight. The water slurry charcoal additive used in the present invention may be dissolved in water in advance and then added to the pulverized coal, or may be added later to the mixture of pulverized coal and water.
Alternatively, the additive may be adsorbed on pulverized coal in advance and then mixed with water. Coal powder to be slurried with the additive of the present invention has a particle size of 1 mm or less, but is not limited thereto. As for the type of coal powder, various types of coal and production areas such as bituminous coal, sub-bituminous coal, and lignite can be used. By using the water slurry charcoal additive of the present invention, the pulverized coal concentration in the water slurry charcoal can be increased by 10 to 30% by weight, and the slurry can be stabilized for a long period of time by preventing sedimentation and separation of the pulverized coal. can be maintained. The present invention will be explained below with reference to Examples. Examples 1 to 7 and Comparative Examples 1 to 4 Water slurry coal additives having the formulation and addition amount shown in Table 1 were dissolved in 100 g of water, 200 mesh coal powder of 75% pass was added thereto, and a homogeneous mixture was added. The mixture was mixed for 5 minutes at 5000 rpm using a mixer (TK Homo Mixer M type, manufactured by Tokushu Kiko Co., Ltd.) to obtain a coal slurry.
The coal concentration was determined when the viscosity of the water slurry coal at 30°C reached 3000 cPs when measured with a B-type viscometer. This water slurry charcoal was transferred to a cylinder and allowed to stand at 30°C, and its stability was evaluated by a rod penetration test. The coal powder used in this example was Datong coal (produced in China).
and has the following properties.

【table】

[Table] Rod penetration test: Pour slurry charcoal into a 500ml graduated cylinder to a height of 18cm and leave it at 30℃. After a predetermined period of time, a 50 mmφ, 20 g glass rod is dropped vertically from the surface into the slurry charcoal, and the time required for the tip of the glass rod to reach the bottom of the cylinder is measured. Stability is evaluated based on the number of days in which the time is within 1 minute.

【table】

【table】

Claims (1)

[Scope of Claims] 1 (a) A nonionic surfactant in which 10 moles or more of alkylene oxide consisting of 95 to 40 mol% of ethylene oxide and 5 to 60 mol% of propylene oxide is added to a compound having one active hydrogen. and (b) an additive for water slurry carbon containing a naphthalene sulfonic acid formalin condensate and/or a salt of an alkylnaphthalene sulfonic acid formalin condensate. 2 The molecular weight of the nonionic surfactant is 1000 to 50000
The additive according to item 1, which is 3 (a) A nonionic surfactant obtained by adding 50 moles or more of ethylene oxide to a compound having a hydrocarbon group having 12 or more carbon atoms and one active hydrogen, and
(b) An additive for water slurry carbon containing a naphthalene sulfonic acid formalin condensate and/or a salt of an alkylnaphthalene sulfonic acid formalin condensate. 4. The water slurry carbon additive according to item 3, wherein the hydrocarbon group is a nonylphenyl group.