PORTMEIRION POTTERIES' RESPONSE

Following the decision not to proceed with the building of a Visitor Centre and new factory the team is now committed to meeting the objectives of the PROMOTE LIFE Project by utilising all known techniques, many as yet unproven, in a working ceramics factory to demonstrate that tackling environmental issues actually saves, not increases costs.

PROGRESS SO FAR

Production Processes

Options have been investigated for processing equipment at each stage of the manufacturing process, consistent with the requirements of PROMOTE LIFE. Many potential suppliers of this equipment have been visited for initial discussions. This task is being undertaken by CERAM, a sub-contractor specialising in advanced ceramic processing technologies.

Equipment Survey reports have been prepared for :

Body Slip de-watering equipment - 8 options evaluated
Roller-head making machines - flexible flatware shown to be advantageous
Pressure casting machines - automatic handling machine identified
Ware dryers - 3 options evaluated
Fettling/sponging machines - 2 systems reviewed
Glaze application - electrostatic dry glazing shown to be beneficial
Fast fire decorating kiln - 3 options evaluated
Packaging - starch based biodegradable material identified

The intention, before the decision not to proceed with the new factory, was to select from the options identified for each process the system giving the best performance in terms of reduced environmental impact. Some of this information has been used to specify equipment for the upgrading of the existing factory. All information gathered in this task is available for dissemination and use by others.

Building Energy Management

CERAM has prepared specifications and undertaken review of available options in each of the following areas :

  • Photovoltaic solar panels
  • Glazing of atrium
  • Insulation
  • Natural ventilation
  • Process heat recovery
  • Combined Heat & Power
  • Air conditioning
  • Energy management systems
  • Water recycling
  • Lighting
  • Fuel cells
  • Renewable energy sources
  • Boiler & building heating
  • Life cycle analysis of building elements

A full survey has been made of energy consumption patterns at the Portmeirion factory in recent years. This is to be used as a benchmark against which to evaluate the improvements made as a result of the PROMOTE LIFE project.
A heat management system supplied by Vickers Electronics has been installed within the main factory area. This is an experimental system, the operation of which is being monitored and evaluated with the intention that, if it is successful, it will be employed within the other company facilities.

After critical consideration of the merits and de-merits for the installation and operation of both a CHP unit and Solar Power System, it was agreed that these units would not be suitable for inclusion into the existing Company facilities.

Water Treatment

The whole subject of water reclamation and treatment is currently under review by a project team. The areas being examined are:
  • The collection and treatment of the water extracted from clay slip during the filtering process. It is intended that this water will be used for cleaning purposes and will reduce the usage of town's water.
  • The more efficient removal of water from reclaimed glaze. This will provide a two-fold benefit; again the reclaimed water will be used for cleaning purposes reducing the usage of town's water; there will also be an improvement in the amount of glaze material removed from the water thus reducing the amount of glaze material being discharged.


Forming & Glazing

Forming : Extensive work has been carried out in developing a new plant for the primary forming of flatware. This development has enabled the replacement of plaster of Paris moulds by long-life porous polymer moulds. This will reduce the environmental impact of the disposal to landfill of waste moulds coupled with a reduction in the energy required to produce moulds.

Waste Heat Recycling : In addition the new plant has been developed to utilise the waste heat from the kiln firing process to dry the ware instead of using a gas fired dryer. This will result in an immediate reduction in energy usage and gaseous emissions. This new plant will be ordered within the next few weeks. Once installed its performance will be closely monitored and the results disseminated.

Glazing : A semi-automatic glaze spraying machine has been installed for the glazing of holloware items with multi-glaze finishes. The machine can apply three different glazes within one cycle. This has reduced energy costs since, when using traditional glazing methods, the ware required drying to enable it to be handled between each glaze application. In addition the quality yields have improved compared to the traditional methods resulting in a reduction in the quantity of waste product produced.

The key parameters in controlling the operation of the in-line glaze spraying machine and hence the quality and yields of the glost flatware are:
  • the linear and rotational speed of the ware through the spray booth
  • the atomisation air pressure applied to the glaze
  • density and viscosity of the glaze slurry
  • flow rate of the glaze slurry from the spray guns

Technology already exists that enables all but the flow rate of the glaze to be controlled and measured. Therefore, a project has been initiated in order to develop a suitable method for the control and measurement of the flow rate of the glaze. Initial findings highlighted that the processes used must be non-intrusive since the highly abrasive nature of the glaze would soon wear intrusive components. It was identified that two possible techniques were appropriate - Ultrasonic and Electromagnetic. Currently a flowmeter utilising electromagnetics is under evaluation.

Gas Fired Kiln Control

A study into the method that can be used for glost firing has revealed that 'once-firing' is not the best method of reducing the environmental impact of the process. Although, for a 'once-fired' system the total energy used may be less than the traditional 'twice-fired' system i.e. where the clay ware is fired to biscuit, the quality yields from a 'once-fire' system are considerably lower. It has been decided, therefore, to create the optimum 'twice-fire' system by product streaming.

The use of intelligent technology, specifically neural networks, to control kilns was first addressed at CERAM in the recent DTI funded "Intelligent Kiln Control" project. This concept having been identified as a key technology for optimising the performance of the kilns it has been included in this project.

To enable the successful development of an intelligent control system, a partnership was formed with CERAM and Neusciences. Neusciences have worked in the field of intelligence technologies since 1989 and are providing their expertise in the application of advanced mathematical and statistical techniques to solve this complex process situation. The intelligent kiln control project aims to develop a system that can predict and advise on the control actions necessary to maintain a set temperature profile.

Temperature and load data have been sent to Neusciences for analysis. Neusciences are to produce a report that will indicate the relative importance of input variables, model performance, likely performance of the finished system, and budgets and timescale for any further modeling work required. In addition, budgets and timescale for implementations of the control system based on that model are to be included.

Click the links below for the Intelligent Kiln Control Reports by :Ceram and Neusciences

Ceram Report

Neusiences Report

Decorating

Work has been carried out in investigating the use of heat release lithographs and techniques in the decoration of simple holloware items. The work carried so far has indicated that the method would not be suitable for all of Portmeirion's tableware items and patterns since in some case, there would be an increase in the cost of the litho requirement. The work is continuing on those items and patterns that would not show a cost increase.

Enamel Kiln Firing

New kiln exhaust stacks for two rotary electric kilns have been developed and installed. These new stacks incorporate technology that condenses the volatile organic compounds (VOC's) and prevents them from being emitted into the atmosphere. The VOC condensate can them be periodically removed and disposed of appropriately.

An evaluation of the enamel firing process has identified that that there would be substantial benefits, in terms of both costs and environmental impact, in changing the method of firing for this process. Electric fired intermittent kilns are currently employed. However, by changing to a gas fired continuous kiln the cost will be less for the same fired result. In addition, since there is a factor of 2.6 in converting gas energy to electrical energy there will be a considerable reduction in the quantity of carbon emitted to the atmospheres as a result of this process. It is intended therefore, that a refurbished continuous gas kiln is installed in the near future.


Dissemination

An important aspect of all LIFE projects is the dissemination of the lessons, both good and bad, that have been learned. So far, the following devices have been utilised for this purpose.

CERAM "Progress" article : A feature article was published on the front cover of the Spring 2001 issue of CERAM's news-sheet "PROGRESS". This is distributed quarterly to over 500 key managers in the ceramic industry.

Manufacturing Seminar : In order to promote the reduction of waste, a seminar on the principles of Lean Manufacturing was presented at the Manufacturing Institute in Manchester on 6th June, 2001.

Ceramic Industry Forum : The CIF has recently been formed in the UK and provides an excellent vehicle through which companies can disseminate progress in a number of areas. A presentation was given to senior managers and directors of a large number of ceramic companies.

CERAM Industry meetings : The PROMOTE LIFE project has been described at several private meetings of ceramic industry professionals. These meetings are organised on a regular basis by CERAM.