Courtaulds Fibres (holdings) Ltd.

Courtaulds (holding) Limited

Gary E Gray

Michael C Quigley

Iain R Jack

Philip Pennicott

Philip J Urwin

A premix storage hopper for storing a hot, viscous, paste-like mixture containing cellulose dispersed in a solution of tertiary amine oxide and water, comprises a vertical contain having a central shaft rotatable about a vertical axis and carrying stirring members and heating means for heating side walls of the container.

Premix storage hopper

A method is provided for filtering shredded cellulose-based material, for example to enable the formation of a mixture containing cellulose dispersed in a solvent for cellulose such as amine oxide. The shredding operation creates both fine particles of cellulosic material ('pulp dust') and large particles of cellulosic material, The shredded cellulosic material is passed through a separator to separate the pulp dust from the large particles of cellulosic material and the pulp dust is subsequently recovered in a filtering process.

Filtering particulate cellulosic-based material

A method is disclosed of forming a premix which is suitable for conversion into a cellulosic dope which can be used to produce cellulosic products. The method involves introducing into a mixing chamber predetermined quantities of shredded cellulosic material and a solution of amine oxide at an elevated temperature and stirring the mixture for a period of time by rotating mixer blades within the mixing chamber at a speed of between 40 and 80 r.p.m..

Formation of a cellulose-based premix

A basis weight scanner using a beta-ray source and an electron detector on opposite sides of a web of wood pulp sheeting is used to calculate the weight of wood pulp advanced past a measuring location (e.g. into a cellulosic fibre production plant).

Flow meter

A filtration system for filtering dope of a solvent-spun fiber manufacturing plant in which dope to be spun flows from a source of supply (10) through a series of filter assemblies (15) (21) (23) to jets (22(b)) of each spinning heads (22). The filtration system comprises, in flow series, a first stage filter assemblies (15) having filter elements with the finest pore size of the series (typically 20.mu.) and a final stage filter assembly (23), immediately upstream of the jets (22(b)) of each spinning head (22). The final stage filter assembly is of the coarsest pore size of the series of filters (typically 80.mu.) and is equal to, or less than, the size of the jet holes (typically 80.mu.). The filter media of intermediate filter assemblies (21) between the first (15) and final (23) stages increase in pore size as one progresses from the first filter assembly (15) to the final filter assemblies (23) along the flow path.

Filtration system

A method of creating a comminuted feedstock of wood pulp for use in a processing plant which includes the steps of mounting a plurality of rolls of wood pulp sheet material of a first range of properties in a first roll stand, drawing sheet material off each roll in the first roll stand and laying the sheet materials one on the other to create a first pluri-layer web, withdrawing the first pluri-layer web from the first roll stand and leading it to a cutting area of a shredding mill, acting on the first pluri-layer web in the cutting area with rotating hooked disc cutters to tear platelets from the first pluri-layer web and to pass the torn platelets to an outlet of the shredding mill, pneumatically conveying the torn platelets away from the outlet using a fan with a bladed member rotating in a fan casing, and beating the torn platelets with the bladed member as they are conveyed through the fan casing to separate the torn platelets into pieces torn from the individual layers making up the first pluri-layer web.

Comminuting wood pulp sheeting

A method of cleaning metal filters of a solvent spun fibre production plant. The method comprises the step of (a) dissolving dope from the filters using a hot solvent for the dope, (b) washing the solvent from the filters using hot water, (c) pyrolysing remnants of dope or solvent in the filters, (d) ultrasonically washing the pyrolysed particles from the filters, (e) reheating the filters to dislodge pyrolysed particles, (f) ultrasonically rewashing the filters and (g) drying the filters.

Cleaning of filters

A method is provided for filtering shredded cellulose-based material, for example to enable the formation of a mixture containing cellulose dispersed in a solvent for cellulose such as amine oxide. The shredding operation creates both fine particles of cellulosic material ('pulp dust') and large particles of cellulosic material. The shredded cellulosic material is passed through a separator to separate the pulp dust from the large particles of cellulosic material and the pulp dust is subsequently recovered in a filtering process.

Growing community of inventors

Westwood Heath, United Kingdom

Gary E Gray