Method of turning vegetable asphalt into superior boiler fuel

Abstract

This invention, which involves a method of turning vegetable asphalt into high-quality boiler fuel, belongs to the field of natural asphalt processing technology. It is intended for acid desaponification of vegetable asphalt at 50 to 100° C., then water washing is performed removing impurities and salt; following this, the asphalt is allowed to stand to separate into layers and the aqueous phase is removed. Neutralization to pH=7 to 8 is then performed using alkali and, after another water wash is performed, the asphalt is allowed to stand to separate into layers and the aqueous phase is separated from it. Then the substance obtained thereby is dried yielding the product. Vegetable asphalt that has undergone modification has the advantages of having low viscosity, generating a small amount of ash, having low sulfur content and a low flash point, and of not being prone to coking when it is burned, and the like, and ensures boiler heat efficiency and also prolongs boiler's useful life and reduces pollution.

1 . A method of turning vegetable asphalt into high-quality boiler fuel, characterized in that this method comprises the following steps:
 (1) Acidification treatment: inorganic acid is added to vegetable asphalt for degumming and slight cracking. Characterized in that the inorganic acid and vegetable asphalt are charged in a reaction vessel, heated while stirring to a temperature of 50 to 100° C., and allowed to react at a constant temperature for 15 to 60 minutes.   (2) The asphalt obtained in step (1) is washed in water, removing impurities and inorganic salts. Characterized in that, during the water wash, the ratio of the volume of water to asphalt is from 0.5:1 to 10:1, the temperature of the water wash is from 50 to 100° C., and the water wash lasts from 1 to 30 minutes.   (3) The substance obtained in step (2) is allowed to stand to separate into layers and the aqueous phase is separated from it.   (4) Using salt, the upper layer of asphalt obtained in step (3) is neutralized to pH=7 to 8, and then the asphalt obtained thereby is washed in water. During the water wash, the ratio of the volume of water to asphalt is from 0.5:1 to 10:1, the temperature of the water wash is from 50 to 100° C., and the water wash lasts from 1 to 15 minutes.   (5) The substance obtained in step (4) is allowed to stand to separate into layers and the aqueous phase is separated from it.   (6) The product is obtained by drying the asphalt obtained in step (5).   
   
   
       2 . The method in accordance with  claim 1  of turning vegetable asphalt into high-quality boiler fuel, characterized in that, during acid treatment, the acid used is one from among the group consisting of hydrochloric acid, nitric acid, and phosphoric acid, or is a mixture of several thereof. 
   
   
       3 . The method in accordance with  claim 1  of turning vegetable asphalt into high-quality boiler fuel, characterized in that, during acid treatment, the quantity of acid added is from 0.1 to 5% of the mass of the raw material. 
   
   
       4 . The method in accordance with any one of  claims 1 ,  2 , or  3  of turning vegetable asphalt into high-quality boiler fuel, characterized in that the front cut fraction obtained in the course of biodiesel production is added to the asphalt after the asphalt has been treated, as an additive. 
   
   
       5 . The method in accordance with  claim 4  of turning vegetable asphalt into high-quality boiler fuel, characterized in that the amount of additive that is added is from 0 to 20% of the total weight.