Dravo Lime Company

Certainteed Gypsum, Inc.

Other

U.S. Department of Agriculture

Dravo Lime, Inc.

Eastroc LLC

Dravco Lime Company

Southern Indiana Gas and Electric Company

Ceriainteed Gypsum, Inc.

John W College

Lewis B Benson

Shane Libunao

Mark Harris

Manyam Babu

David Corbin

Shiaw C Tseng

Yungli J Lee

Felipe J Yanes

Russell C Forsythe

Choung-Houng Lai

James H Wilhelm

Michael J Lemberger

Isaac K Cherian

Gaurav V Pattarkine

Phillip G Morgan

Joel H Beeghly

Robert Mark Golightley

Sang-Ho Lee

Bryan R Beyer

Chris Hilton

Dennis L Glancy

Yu-Zhi Kiang

Jim Wilhelm

George Glavin

David McKinney

Ralph B Clark

Virupax C Baligar

K Dale Ritchey

R Mark Golightley

Helen Ilyashenko

The present invention relates to a system and method for the production of gypsum board using starch pellets. In accordance with the present disclosure, the starch necessary for board formation is provided in the form of starch pellets. These pellets are mixed with a gypsum slurry in a mixer. The pellets are initially insoluble and do not dissolve. However, during subsequent drying stages, the pellets become soluble and dissolve into the gypsum phase. This both provides the desired starch component and also results in the formation of voids within the set gypsum.

System and method for the production of gypsum board using starch pellets

The present disclosure relates generally to building materials, such as building boards, having improved strength and reduced shrinkage. More particularly, the present disclosure provides building compositions comprising Struvite-K (KMgPO.6HO), Syngenite (KCa(SO).HO), and one or more silicate additives suitable for use in building materials.

Struvite-K/Syngenite building compositions comprising silicate materials and building articles such as wallboards made therefrom

The present invention relates to an improved method for using heat energy in a gypsum board plant. More specifically, the method contemplates taking heat from a gasifier, or other alternative heat source, and using it to dry gypsum boards. In order to control humidity levels, this heat is delivered to one or more board dryers via a heat exchanger.

Method for the use of heat energy from gasification sources in gypsum board production

Disclosed is an apparatus and method for capturing the hot humid gases from a gypsum board dryer and utilizing those gases in the production of a synthetic gas (referred to as 'syngas'). The syngas produced can then be utilized within a gypsum board plant to reduce the amount of natural gas needed. The method utilizes the heated water vapor (HO) and carbon dioxide (CO) found within the flue gas of a board dryer. The HO and COare used in a gasification process to yield the syngas.

System and method for using board plant flue gases in the production of syngas

Disclosed are various methods for reducing levels of elemental sulfur within gypsum products such as wall board. Gypsum sometimes includes increased levels of elemental sulfur. Such sulfur can be corrosive and otherwise harmful at elevated levels. The disclosure contemplates reacting the elemental sulfur with copper to copper sulfide. This reaction has the benefit of reducing the levels of elemental sulfur present within the final gypsum product. The copper can be added at any of a variety of locations in the manufacturing process. This is a very efficient method for reducing elemental sulfur in the production of gypsum products.

Method for reducing elemental sulfur in gypsum products

Disclosed is an apparatus and method for capturing the hot humid gases from a gypsum board dryer and utilizing those gases in the production of a synthetic gas (referred to as 'syngas'). The syngas produced can then be utilized within a gypsum board plant to reduce the amount of natural gas needed.

The present invention relates to a system and associated method for the production of gypsum in manufacturing plant. More specifically, the invention relates to the production of alpha-type gypsum in a gypsum board manufacturing plant. The system yields increased efficiencies by capturing heat given off during processing steps and using that heat to reduce the energy needed for calcination. The invention finds particular application in the production alpha-type gypsum. The present invention is described in greater detail hereinafter in conjunction with the following specific embodiments.

System and method for the production of gypsum using heat recovery

System and method for the production of alpha type gypsum using heat recovery

A hydroseparator for separating particles based on the differences in settling rates such as for separating fly ash from gypsum includes a substantially cylindrical side wall closed at its bottom end by a floor. A laminar upflow is created through the hydroseparator by adding dilution water to the bottom of the hydroseparator and removing most of the added dilution water from the top of the hydroseparator. The remaining volume of liquid is removed in an underflow. The hydroseparator is divided into at least two sections by a baffle that extends about the interior of the side wall. An inlet is disposed in the center of the hydroseparator slightly above the baffle such that the material added to the hydroseparator to be separated is inserted into the section of the hydroseparator completely surrounded by the baffle. The velocity of the upflow is controlled such that it is not fast enough to cause the faster-settling gypsum particles to rise but is fast enough to cause the slower-settling fly ash particles to rise with the upflow. The upflow thus separates the fly ash from the gypsum and floats the fly ash to the top of the hydroseparator where it is removed in the overflow. An agitator is provided in the lower portion of the hydroseparator to evenly distribute wash water and to keep the gypsum fluid.

Method and apparatus for separating fast settling particles from slow settling particles

A method of purifying a flue gas desulfurization aqueous waste slurry containing calcium-sulfur salts and residual solid grits, fly ash, carbon and oils by supplying the aqueous waste slurry to a screening station to remove the grits, passing the grit-free aqueous waste slurry to a magnetic separator to remove fly ash components, and transferring the aqueous slurry to a floatation cell to remove carbon and oils therefrom. A purified aqueous slurry of calcium-sulfur salts is removed from the floatation cell which can be used in producing quality plaster, wallboard, or feedstock in producing &agr;-hemihydrate gypsum.

Method of purifying flue gas waste slurries for use in gypsum production

Growing community of inventors

Pittsburgh, PA, United States of America

John W College