Cement, Energy and Environment

e) Assess the potential impact on process stability and quality of the fina l product; f) Assess the effect the waste may have on plant emissions and whether new equipment or procedures are needed to ensure that there is no negative impact on the environment; g) Determine what materials analysis data the waste supplier will be required to provide with each delivery, and whether each load needs to be tested prior to off-loading at the site. Commonly restricted wastes Develop a uniform list of restricted wastes valid for the plant based on the previous impact assessment and the plants raw material and fuel composition. Certain cement companies choose not to treat the following wastes and materials: a) Electronic waste; b) Entire Batteries; c) Infectious and biological active medical waste; d) Mineral corrosives; e) Explosives; f) Asbestos; acids g) Radioactive waste: and h) Unsorted municipal waste; i) Unknown/unidentified wastes. Individual companies may exclude additional materials depending on local circumstances and company policy. Shipments crossing international boundaries and classified as hazardous waste under the Basel Convention must meet with the requirements of the Convention. Risky wastes When the waste composition cannot be described in detail (e.g. small amounts of pesticides or laboratory chemicals), the cement plant operator and the pre-processing facility may agree with the waste producer on specific packaging requirements, making sure that the waste will not react during transport, or within containers. For example, risks may arise from: a) Wastes with phosphides; b) Wastes with isocyanates; c) Waste with peroxides; d) Wastes with alkaline metals or other reactive metals; e) Cyanide with acids; f) Wastes forming acid gases during combustion; g) Wastes with mercury and thallium. Check list for acceptance control Delivered wastes must generally undergo specific admission controls, whereby the previously received declaration by the waste producer provides the starting point. After comparison by visual and analytical investigations with the data contained in the declaration, the waste is either accepted and allocated to the appropriate pre-processing and/or storage area, or rejected in the case of signifi cant deviations. Prior to signing any commercial contract, the cement plant operator must make sure that: a) The waste generator, collector, pre-processing facility provides adequate information on composition and risk of the material: b) They do not accept any substances , compounds or preparation which are not allowed or on the "negative list"; c) They prohibit blending of incompatible materials and perform compatibility tests if needed; d) They perform sampling on the site of the generator, collector or the pre- processing facility and analysis before acceptance of commercial contracts. Sampling and analysis can be done by own or external, certified laboratories; e) They do not start transportation to plant site before completion of the acceptance process. The acceptance process does not replace sampling and analysis of waste deliveries at the plant sites; f) They communicate the inherent safety and health risks indicated by the waste generator, collector, pre processor or identified by the sample analysis to the downstream operations (transport, pre- and co– processing) to ensure that PPE and installations are adapted accordingly; g) They provide simple, clear and practical handling procedures, based on the material properties, to each person who will work with the waste; h) They provide the commercial employees with adequate training in chemistry to allow them to enforce the waste acceptance criteria. Feeding of waste to the kiln must ensure exposure to: a) Sufficient temperature; b) Sufficient retention time; c) Sufficient mixing conditions; d) Sufficient oxygen. 80 -~