SK18002001A3 - Method of treatment of filter cake from filtration of polymer polyols - Google Patents

Abstract

There is described a method of treatment of filter cake from manufacturing of polyetherpolyol by which filter material - expanded SiO2 and filter diatomaceous earth contaminated by alkali salt and polyetherpolyol is in the presence of water exposed to temperature from 80 to 85 °C and consequently is solute alkali salt, filter diatomaceous earth and expanded silicon dioxide saturates to aqueous phase by formation surface polyetherpolyol layer.

Description

Technical field

The invention relates to a method of treating a filter cake from the filtration of polymeric polyols. The invention falls within the field of recovery and disposal of hazardous waste.

BACKGROUND OF THE INVENTION

At present, the final purification while occurring is used in the formation with disposal due to the production of polymer polyols and as a substitute for the extraction of the filter cake. The problem of this filter cake, namely the high content of polymer polyols. The polyols thus formed

The combustion of substances by polymer treatment, inorganic, the fact that it is up to 70% but mainly by wt.

or wt.

With respect to waste containing 30 to 40%, it is possible to dispose of it by incinerating waste containing 60 to be economically expensive.

This is a waste with high to fall out lining furnace

Since the presently unresolved and environmentally-friendly treatment method would result in phosphorus, incinerator, economically wastes with a preferred polymeric polyol content, this problem had to be solved, which ultimately resulted in the filter cake treatment method of the present invention.

SUMMARY OF THE INVENTION

The aforementioned drawbacks are largely eliminated by a process for treating a filter cake containing 40 to 60 wt. alkali metal salts of pyrophosphate (P ₂ O ₇₎ ⁴ ', 30 to 40% by weight. % polyether polyol, up to 10 wt. % diatomaceous earth (Mg SiO ₃ ), 5 to 10 wt.

of expanded silica (perlite) so that the content of polymer polyols is minimal. SUMMARY OF THE INVENTION The invention is characterized in that water is added to the filter cake in a weight ratio of 0.5: 1 to 4: 1 and, with stirring, the mixture is heated to a temperature of 80 to 85 ° C. It is also possible in the first treatment step to dispense the waste - filter cake into heated water at 50 to 60 ° C. After 20 to 40 minutes, the entire contents can be pumped into a separating column and stratified. After cooling to 30-35 ° C, the aqueous layer is separated from the polyether polyol layer. The soluble alkaline diphosphate salt, filter diatomaceous earth and expanded silica pass into the aqueous phase and a layer of polyether polyol excel on the surface. After separation of the phases, these are separately processed.

It is advantageous that after the treatment of the filter cake by the method according to the invention, the filter cake can still be utilized, where by means of simple technological operations 30 to 40 wt. % of polyether polyol as feedstock, or can be used for energy purposes with a calorific value of 29,000 kJ.kg ^-1 , which is the calorific value of hard coal.

DETAILED DESCRIPTION OF THE INVENTION

In this example of a particular embodiment of the invention, a method of treating a filter cake devalued by the polyether polyol and bisphosphate according to the invention is described, when the components of the treated waste are recovered. For the treatment of the deteriorated filter cake, waste of the following composition was used:

Alkaline diphosphate salt ........... 55 wt.

Polyether polyol ........................ 35 wt.

% Diatomaceous earth ................................. 3% wt.

Expanded silica ......... 7 wt.

In the first treatment step, the waste-filter cake was added to the heated water at 50-60 ° C in a 1: 1 weight ratio. The mixture was heated to 80-85 ° C with stirring. The soluble alkaline diphosphate salt, filter diatomaceous earth and expanded silica pass into the aqueous phase and a layer of polyether polyol is formed on the surface. After 30 minutes, the entire contents are pumped to a separating column and allowed to stratify. After cooling to 30-35 ° C, the aqueous layer is separated from the polyether polyol layer.

Separated polyether polyol was characterized by the following composition:

Fischer water content ................ 0.0165 wt.

Combustion heat and calorific value ........................... 28 935 kJ.kg - ¹

Cleveland flash point .......... 232 ° C.

Industrial usability

The process of treating a filter cake devalued with diphosphate and polyether polyol according to the present invention finds application in the technological process for the production of polyether polyols, in particular in the production of Slovaprop.

Claims (4)

PATENT CLAIMS Process for the treatment of a filter cake from the production of polyether polyol containing an alkali metal salt of diphosphate, polyether polyol, filter diatomaceous earth and expanded silica, characterized in that by metering, a mixture of water and filter cake in their weight ratio of 0.5: 1 to 4: 1 it is subsequently heated to a temperature of 80 to 85 ° C to release the polyether polyol. Process for treating a filter cake from the production of polyether polyol according to claim 1, characterized in that in the process of heating the water and filter cake to a temperature of 80 to 85 ° C, they are stirred. Method for treating a filter cake from the production of polyether polyol according to claim 1, characterized in that the water has an inlet temperature of 50 to 60 ° C when forming a mixture of water and filter cake. Method for treating a filter cake from the production of polyether polyol according to claim 1, characterized in that 20 to 40 minutes after dosing the mixture is followed by pumping the treated mixture into a separating column and cooling it to 30 to 35 ° C with self-separating polyether polyol. subsequent use.