Waste oil regeneration method by phosphor salt flocculation, CO2 stirring and clay refining

Abstract

A waste oil regeneration method by phosphor salt flocculation, CO2 stirring and clay refining relates to waste lubricating oil processing, comprises steps of pretreatment for water and debris separation, first alkali washing, first thermal dehydration, contacted refining, press filtration, secondary alkali washing and secondary thermal dehydration. The step of pretreatment for water and debris separation is characterized in that a Na3Po4 solution (weight concentration being 5%) which accounts for 5 wt% of waste oil is added while oiling, and settlement lasts for 4 hours after stopping heating and agitating; the step of first alkali washing is characterized in that alkali lye is a Na3Po4 solution (concentration being 5%) which accounts for 5 wt% of waste oil; the step of contacted refining is characterized in that heating and agitating are carried out until there is no bubble, and then the solution is heated to 150 DEG C; the step of press filtration is characterized in that the solution is cooled to 120 DEG C before press filtration and then oil is pumped; and the step of secondary alkali washing is characterized in that alkali lye is a Na3Po4 solution (concentration being 5%) which accounts for 2 wt% of waste oil, wherein the gas for agitating at each step is CO2 gas. The invention has the following advantages: during the pretreatment process, Na3Po4 is adopted for oil-water and oil-residue separation, flocculating efficiency is good, effective ingredients of various additives are preserved; and CO2 effectively prevents oxidation of oil and has a good flocculation effect.

Description

technical field [0001] The present invention relates to waste lubricating oil treatment, especially a kind of phosphorus salt flocculation CO 2 Gas-stirred white clay refining waste oil regeneration method. Background technique [0002] Compressors in nitrogen fertilizer enterprises produce a large amount of high-viscosity waste lubricating oil every day. Enterprises generally have oil treatment stations to deal with waste lubricating oil, and the waste oil is regenerated and then used for lubrication of equipment and machines. [0003] Waste oil regeneration processes are generally divided into three categories: [0004] The first category is repurification. Including sedimentation, centrifugation, filtration, flocculation. One or several in combination, simple regeneration, the main purpose is to remove water in waste oil, generally suspended mechanical impurities and mechanical impurities stably dispersed in colloidal state. [0005] The second category is re-refineme...

AI Technical Summary

Problems solved by technology

[0016] In the above-mentioned process, if the primary alkaline washing is replaced by the sulfuric acid method to remove the oxidized colloids in the oil, although the effect is good, this method will destroy all kinds of additives that are still effective in the waste oil, resulting in a decline in the physical and chemical properties of the regenerated oil. , when the produced base oil is blended into lubricating oil, it is inevitable to increase the amount of additives

At the same time, the national environmental protection department has explicitly banned the use of sulfuric acid-clay process, the reason is that the sulfuric acid decoking method will produce toxic waste gas and waste residue, and the waste residue is difficult to degrade and dispose of

Simple white clay contact refining or fixed bed adsorption refining, the device is pressurized high-temperature distillation adsorption treatment, the investment is large, the amount of white clay is large, the safety level is high, and the production cost is relatively high