Patent GB-435351-A (GB)
Title: Improvements in or relating to the precipitation of dust
IPC: B27K3/28
Filed: 1934-10-08
Abstract: Finely distributed dust especially rock dust in mines is precipitated by means of foam prepared by introducing air or other gases in fine division into aqueous dispersions or solutions containing wetting agents and solvents having the formula R1OCH2(CH2OCH2)nCH2OR2 in whic R1 is hydrogen or alkyl, R2 is hydrogen or alkyl, aralkyl or aryl and n is a whole number or if R1 and/or R2 are hydrogen, nought or a whole number.  Urea, thiourea, degraded albuminous compounds or other substances which favour the production of foammay also be present. In an example, oleic acid-N-methyltaurine containing about 30 per cent of inorganic salts, diethyleneglycolmonoethylether and urea or thiourea are used for the preparation of foam. Diethyleneglycolmonomethylether triethyleneglycol monomethyl and ethyl ether, tetraethyleneglycolmonobutylether, diethyleneglycoldiethylether, monocresyl or monoxylenyl ethers of mono, di, tri- or tetraethyleneglycol are mentioned as suitable solvents.  Specified wetting agents are: highly sulphonated vegetable and animal oils, alkali metal salts of alkylated aromatic sulphonic acids, sulphuric esters of higher alcohols, condensation products of fatty acids with hydroxy and amino alkylsulphonic acids and reaction products of ethyleneoxide upon organic hydroxy, carboxylic and amino compounds.  Specification 313,621, [Class 124], is referred to. Diethyleneglycolmonoethylether may be made by alkylation of the monoethyl ether or by hydrogenation of the addition product of acetylene and diethylene glycolvinylether.  The Specification as open to inspection under Sect. 91 comprises also the use of the foam for combating fires.  In further examples, the following mixtures are used after adjustment of the hydrogen ion concentration for the formation of foam: (1) the reaction product of ethylene oxide and oleyl alcohol, and diethyleneglycol monobutylether with or without dimethyl cellulose; (2) sodium salt of dibutylnaphthalene sulphonic acid, triethylene glycolethylether and the condensation product of palm kernel fatty acid chloride and isethionic acid sodium salt; (3) oleic acid tauride, ethylene glycol monocresylether and the sodium salt of polymerized acrylic acid; (4) the reaction product of ethyleneoxide and coconut fatty acid ethanolamide, diethyleneglycolmonobutylether, sulphonated castor oil and thiourea. This subject-matter does not appear in the Specification as accepted.ALSO:Finely distributed dust, especially rock dust in mines is precipitated by means of foam prepared by introducing air or other gases in fine division into aqueous dispersions or solutions containing wetting agents and solvents having the formula R1OCH2(CH2OCH2)n CH2 OR2 in which R1 is hydrogen or alkyl, R2 is hydrogen or alkyl, aralkyl or aryl and n is a whole number, or if R1 and/or R2 are hydrogen, nought or a whole number.  Urea, thiourea, degraded albuminous compounds or other substances which favour the production of foam may also be present.  In an example, oleic acid-N-methyltaurine containing about 30 per cent of inorganic salts, diethyleneglycolmonoethylether and urea or thiourea are used for the preparation of foam. Diethyleneglycolmonomethylether, triethyleneglycol monomethyl and ethylethers, tetraethyleneglycolmonobutylether, diethyleneglycoldiethylether, monocresyl or monoxylenyl ethers of mono, di, tri or tetraethyleneglycol are mentioned as suitable solvents.  Specified wetting agents are: highly sulphonated vegetable and animal oils, alkali metal salts of alkylated aromatic sulphonic acids, sulphuric esters of higher alcohols, condensation products of fatty acids with hydroxy and amino alkylsulphonic acids and reaction products of ethyleneoxide upon organic hydroxy, carboxylic and amino compounds. Specification 313,621, [Class 124], is referred to.  The Specification as open to inspection under Sect. 91 comprises also further examples in which the following mixtures are used after adjustment of the hydrogen ion concentration for the formation of foam: (1) the reaction product of ethylene oxide and oleyl alcohol, and diethyleneglycolmonobutylether with or without dimethylcellulose; (2) sodium salt of dibutylnaphthalene sulphonic acid, triethyleneglycolethylether and the condensation product of palm kernel fatty acid chloride and isethionic acid sodium salt; (3) oleic acid tauride, ethylene glycol monocresylether and the sodium salt of polymerized acrylic acid; (4) the reaction product of ethylene oxide and coconut fatty acid ethanolamide, diethyleneglycolmonobutylether, sulphonated castor oil and thiourea.  This subject-matter does not appear in the Specification as accepted.