US 2024/0409459 A1 · WASTE-TO-ENERGY PRODUCTION CONJOINED WITH PORTLAND CEMENT PRODUCTION

Abstract

A Portland cement production (PCP) process is conjoined with a waste-to-energy (WTE) process using refuse-derived fuels (RDFs). Both processes operate simultaneously to reduce harmful compounds being discharged into the environment. The PCP and WTE processes are conjoined by borrowing a minor portion of pre-heated comminuted limestone from a PCP process feedstream and diverting it to the WTE process. Some of the pre-heated comminuted limestone is converted to CaO. The calcium compounds from the pre-heated comminuted limestone act as a fluxing agents and sorbents to bind with and remove undesired impurities, such as elemental particulate matter, excess CO2 and acid gasses associated with sulfur and chlorine that are released during the pyrolization of RDFs. The ash, char waste and reacted calcium compounds from the pyrolization process can be comingled and returned to the PCP process as a secondary cement meal feedstock.

Claims18

Dependent claims

A pair of simultaneous processes which are conjoined in order to share infrastructure, reduce thermal expenditures, and reduce pollution, said conjoined process comprising:

a Portland cement production (PCP) process which receives comminuted limestone as a primary material input for the PCP process, said comminuted limestone being heated in a first preheater;
a waste-to-energy (WTE) production process which receives refuse-derived fuels (RDF) as a primary material input and a minor portion of the comminuted limestone following its heating in the first preheater, said minor portion functioning as a secondary material input for the WTE process, and being commingled with the RDF and functioning as a fluxing agent and sorbent to bind with and remove undesired impurities during pyrolysis of the RDF in a pyrolysis gasifier during production of syngas;
and
means for removing pyrolysis byproducts, which include reacted comminuted limestone, carbonaceous char, and ash, from the pyrolysis gasifier, and transporting them back to the PCP process, where they are commingled with a major portion of the comminuted limestone from the first preheater, and cementitious meal materials in a second stage preheater before being sent to a high-temperature rotary kiln, where they are sintered and vitrified into cement clinkers.

1 more element

A conjoined manufacturing facility for Portland cement production (PCP) and the conversion of pulverized refuse-derived fuels (RDF) obtained from municipal solid waste (MSW) into usable liquid fuels, said conjoined manufacturing facility comprising:

a supply of quaried limestone used as a principal feedstock of the PCP process;
a comminutor for converting the quaried limestone into a comminuted limestone feedstream;
a first-stage preheater for heating the comminuted limestone feedstream;
a supply of RDF;
a pyrolysis gasifier in which to partially convert the RDF to syngas;
a second slipstream for diverting a minor portion of the comminuted limestone to the pyrolysis gasifier where it is comingled and heated with the RDF, said comminuted limestone within the pyrolysis gasifier acting as a fluxing agent and sorbent to bind with and remove undesired impurities during pyrolysis of the RDF in the pyrolysis gasifier during production of syngas;
and
a third slipstream for returning comminuted limestone, that has bound with undesired impurities within the pyrolysis gasifier, to the heated comminuted limestone feedstream for use as a secondary feedstock in the production of Portland cement.

5 more elements

Dependencies are inferred from the claim text.

Waste-to-energy production conjoined with portland cement production

Life of this patent

Waste-to-energy production conjoined with portland cement production

Life of this patent

Abstract

Claims18