Bitumen product

Patent metadata

Field	Value
Publication number	US-12258461-B2
Application number	US-202017642805-A
Country	US
Kind code	B2
Filing date	Sep 23, 2020
Priority date	Sep 23, 2019
Publication date	Mar 25, 2025
Grant date	Mar 25, 2025

Abstract

A bitumen product including bitumen and a mineral filler. In order to reduce the specific weight of the bitumen product while allowing sufficient scaling effect, the mineral filler contains expanded perlite grains, the expanded perlite grains having a closed-cell surface, and the expanded perlite grains having a closed-cell surface are not ground.

First claim

The invention claimed is:

1. A bitumen product comprising bitumen as well as a mineral filler, wherein the mineral filler comprises expanded perlite grains, which expanded perlite grains have a closed-cell surface, and expanded perlite grains, which expanded perlite grains have an open-cell surface,
wherein a proportion of expanded perlite grains having a closed-cell surface is greater in % by weight than a proportion of expanded perlite grains having an open-cell surface,
wherein the expanded perlite grains with closed-cell surface are unground,
wherein the expanded perlite grains with closed-cell surface have a bulk density of between 90 kg/m 3 and 550 kg/m 3 ,
wherein the expanded perlite grains with closed-cell surface have a particle size of between 5 μm and 2000 μm, and
wherein the expanded perlite grains with closed-cell surface are present in amounts of between 1 wt. % and 20 wt. %.

2. The bitumen product according to claim 1 , wherein the expanded perlite grains with closed-cell surface have a bulk density of between 200 kg/m 3 and 380 kg/m 3 .

3. The bitumen product according to claim 1 , wherein the expanded perlite grains with closed-cell surface have a particle size of between 25 μm and 1200 μm.

4. The bitumen product according to claim 1 , wherein the expanded perlite grains with closed-cell surface are present in amounts of between 2 wt. % and 12 wt. %.

5. The bitumen product according to claim 1 , wherein the bitumen is present in amounts of between 75% and 85% by weight.

6. A bitumen product according to claim 1 comprising bitumen and a mineral filler with a bound blowing agent, which mineral filler comprises expanded, unground perlite grains, wherein the mineral filler being obtainable by a process in which the perlite grains are
brought into a feed opening at one end of a furnace shaft,
transported in a conveying direction along a heat treatment line,
during transport through the heat treatment section heated to a critical temperature at which the perlite grains become plastic and start to expand due to the blowing agent,
after heating to the critical temperature heated to a second temperature above the critical temperature, which second temperature is below a third temperature, at which third temperature the surface of the perlite grains bursts open, and wherein the second temperature is selected dependent on a density of the expanded perlite grains,
and the expanded perlite grains are discharged at another end of the furnace shaft.

7. The bitumen product according to claim 1 , wherein the expanded perlite grains with closed-cell surface have a particle size of between 50 μm and 600 μm.

Assignees

• Omya Int Ag

Inventors

• Kremer Hartmut

Classifications

• C08K2201/005

  Additives being defined by their particle size in general · CPC title

• C08K7/24

  inorganic · CPC title

• C04B20/1003

  Non-compositional aspects of the coating or impregnation · CPC title

• C04B20/066

  in shaft or vertical furnaces · CPC title

• C04B26/26 Primary

  Bituminous materials, e.g. tar, pitch {(C08L95/00 takes precedence)} · CPC title