1 INTRODUCTION. Box 1: What is coke?

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1 1 INTRODUCTION Coke, produced through the heating of coal in the absence of air, is used in the steel and ferro-alloy industries in South Africa. ArcelorMittal South Africa, a major steel producer in the country, operates coke ovens in Newcastle, Vanderbijlpark and Pretoria. ArcelorMittal South Africa is investigating the feasibility of re-commissioning an existing coke oven battery at its. The project is proposed, as a coke oven battery, which has reached the end of its lifespan has been decommissioned at the Vanderbijlpark Works. This has lead to a shortage of coke supply in the market and an increase in imports. A second coke oven battery in Vanderbijlpark will also be decommissioned in the near future. ArcelorMittal South Africa needs to protect its market share through unlocking additional coke production capacity in South Africa. The proposed project will also provide an opportunity to upgrade associated facilities to comply with the requirements of the Air Quality Act. Box 1: What is coke? When coal is heated to temperatures of around C in an air-tight oven, the water, coal-gas and coal-tar are driven off. The material that is left is referred to as coke. Coke is a dark grey, hard and slightly porous material. 2 ENVIRONMENTAL IMPACT ASSESSMENT 2.1 Overview of environmental legislation in South Africa There are various Acts and regulations that regulate environmental management in South Africa, as well as over 135 different by-laws that regulate industrial activities. The proposed Re-commissioning of the Coke Oven Battery must adhere to all relevant legal requirements pertaining to environmental management. The most important of these are: National Environmental Management Act (NEMA) (Act 107 of 1998), which is South Africa s overarching environmental legislation. National Environmental Management: Waste Management Act (NEM: Waste Act) (Act No. 59 of 2008) National Environmental Management: Air Quality Act (NEM: Air Quality Act) (Act 39 of 2004). National Water Act (Act 36 of 1998) Occupational Health and Safety Act. 2.2 EIA Regulations and listed activities A number of components of the proposed development are listed activities in the EIA Regulations under the National Environmental Management Act (NEMA) (Act No. 107 of 1998). A summary of relevant legislation and listed activities (EIA Regulations, 21 April 2006) is provided in Table 1. Table 1: Summary of applicable listed activities from relevant legislation Legislation and listed activity Component of development Listed activities in GN 386 in terms of the National Environmental Management Act 1 The construction of facilities or infrastructure, including associated structures or infrastructure, for (c) the storage of 250 tons or more but less than tons of coal; 24 The recommissioning or use of any facility or infrastructure,. after a period of two years from closure or temporary closure, for - (c) facilities for any process or activity, which require permission, authorisation, or further authorisation, in terms of legislation governing the release of emissions, pollution, effluent or waste prior to the facility being recommissioned unless the facility for the process or activity is included in the list of waste management activities published in terms of section 19 of the National Environmental Management: Waste Act, 2008 (Act No. 59 of 2008) in which case 1 Extension of the coal storage area with storage space for an additional ton coal Re-commissioning of the coke oven battery, which requires an application for amendment (further authorisation) of the existing Air Pollution Prevention Permit for the.

2 Legislation and listed activity the activity is regarded to be excluded from this list. 25 The expansion of or changes to existing facilities for any process or activity, which requires an amendment of an existing permit or license or a new permit or license in terms of legislation governing the release of emissions, pollution, effluent unless the facility for the process or activity is included in the list of waste management activities published in terms of section 19 of the National Environmental Management: Waste Act, 2008 (Act No. 59 of 2008) in which case the activity is regarded to be excluded from this list. Listed Activities in GN 387 in terms of the National Environmental Management Act Component of development Expansion of the gas treatment plant; Repair, upgrading and recommissioning of the existing coke oven battery. 1 The construction of facilities or infrastructure, including associated structures or infrastructure, for - (d) the refining of gas, oil and petroleum products. Construction of facilities for cleaning of gas in the gas treatment plant. (j) the bulk transportation of dangerous goods using pipelines, funiculars or conveyors with a throughput capacity of 50 tons or 50 cubic metres or more per day; NEM: Waste Act GN Category B 7 The treatment of effluent, wastewater or sewage with an annual throughput capacity of cubic metres or more. Transfer of coke oven gas in pipelines. Coke oven gas is classified as a dangerous good (flammable gas) in South African National Standard 0228 (SANS 0228). Additional ammonia removal from coal water in the gas treatment plant with a throughput of ~ m 3 per annum. Therefore an EIA must be conducted to ensure that the environmental effects of the proposed project are taken into consideration. An application for authorisation of the activities, listed above, in terms of the National Environmental Management Act, 1998 (Act No. 107 of 1998), as amended and the Environmental Impact Assessment Regulations, 2006 (Version 1) was submitted to the Kwazulu-Natal Department of Agriculture, Environmental Affairs and Rural Development (KZN DAEARD). The department has confirmed that the Scoping process may proceed under number DC25/0011/2010. In addition, a listed activity under the National Environmental Management: Waste Act (Act No. 59 of 2008) and an activity which results in atmospheric emissions (NEM: Air Quality Act) which have or may have a significant detrimental effect on the environment, will be triggered by the proposed re-commissioning. As such, applications will also be submitted for an amendment to the existing Air Pollution Prevention Permit (APPA) and a Waste License. 2.3 How will the lead authority take a decision? The KZN DAEARD is the lead authority that will decide whether to formulate an environmental authorisation or not, which is a decision on whether the proposed development may proceed or not. This Department will consider the EIA process and findings of the assessment in order to take a final decision on whether the project may proceed or not. The KZN DAEARD will take into account the issues that have been raised by I&AP s and the significance of identified impacts. During the decision-making process the KZN DAEARD will also consult with other relevant government departments, to obtain input before making a final decision. The KZN DEARD will formulate an environmental authorization, which is a decision on whether the proposed development may proceed or not (positive or negative authorisation). Should the project be authorised it is likely that a range of conditions will be stipulated and license applications will be processed. The application for amendment of the existing APPA permit will be considered by the Amajuba District Municipality, while an application for a Waste license will be considered by the National Department of Water and Environmental Affairs (DWEA). 3 THE PROPONENT 3.1 The existing ArcelorMittal South Africa ArcelorMittal South Africa is the largest steel producer in South Africa, with steel operations in Vanderbijlpark, Vereeniging, Newcastle, Saldanha and Pretoria. The Newcastle Steel operations were established in the early 1970 s 2

3 on its present site in the northern part of South Africa s KwaZulu Natal Province. The early operations were supplied with coal from the nearby Kliprivier and Utrecht coal fields and with electricity from a coal-fired power station to the south of Newcastle (Wilson and Anhaeusser, 1998). The employs some staff. Operations on site are representative of an integrated iron and steel works and include coke oven batteries, a sinter plant and blast furnaces in the iron-making area and basic oxygen furnace and continuous casters in the steel-making area. Steel products are further processed, rolled and milled at four rolling mills. 3.2 Project need The principal motivation for the replacement of some existing coke oven batteries is a stable supply of metallurgical coke (refer to Box 2) to the ArcelorMittal South Africa blast furnaces. Coke is used as a fuel and reducing agent (removes oxygen) in smelting iron ore in the blast furnace and has been used for this purpose for almost three hundred years (refer to Box 3). The liquid iron, produced in this process, is an essential ingredient in steel manufacturing, which is the core business of ArcelorMittal South Africa. Local ferrochrome producers source approximately 41% of coke, an essential ingredient in the ferrochrome production process, from ArcelorMittal South Africa. The loss of production from the coke oven battery in Vanderbijlpark will result in loss of market share for ArcelorMittal South Africa in the country. Ferro-alloy coke (refer to Box 2) will probably be imported from China, but Zimbabwe, the USA, the UK, Poland and the Ukraine are developing supply channels. The demand for ferro-alloy coke is predicted to increase by some 20% during the next six years. The Re-commissioning of the existing coke oven battery is proposed in response to the present and predicted demand for coke in the South African ferrochrome industry, as well ensuring a stable coke supply for steel manufacturing. Box 2: Different types of coke Coke acts as a reducing agent (removes oxygen) in furnaces and is also a source of energy. Metallurgical coke is used in blast furnaces to produce iron. It is harder and more stable than ferro-alloy coke. Ferro-alloy coke is used in the ferrochrome industry. It is chemically more reactive than metallurgical coke. Different coal mixtures are required to produce the two different types of coke. Box 3: Short history of coke (Source: Wikipedia) The use of coke as a fuel was pioneered in 17th century England to counter European deforestation. Wood was becoming increasingly scarce and expensive, and coal's fumes, particularly smoke and sulphur compounds, disqualified it from many applications, including cooking and iron smelting. At this stage charcoal was used to produce iron. In 1603, Sir Henry Platt suggested that coal might be charred in a manner similar to the way charcoal is produced from wood. Abraham Darby set up a coke-fired blast furnace to produce cast iron in Coke's superior crushing strength allowed blast furnaces to become taller and larger. The ensuing availability of inexpensive iron was one of the factors leading to the Industrial Revolution. 3.3 Upgrading and improvements at the The following are some ongoing initiatives, relevant to the proposed Re-commissioning of the Coke Oven Battery Upgrading of water management infrastructure ArcelorMittal South Africa (previously Iscor Newcastle), compiled a long term Water Management Strategy to be implemented in a phased manner from 1999 to The objective of the strategy is to achieve Zero Effluent Discharge, which has been stipulated as a legal requirement by DWEA (previously DWAF). A number of water treatment facilities have been constructed since The biological treatment plant has not functioned as envisaged and after a number of investigations, additional infrastructure is being planned to reach ZED status. Table 2 provides an overview of water treatment infrastructure and upgrades as part of the Zero Effluent Discharge (ZED) project. 3

4 Table 2: Components of the Zero Effluent Discharge project Description A number of bunded areas will be roofed Comment Reduce the volume of storm water routed to treatment plants. Improves the management of storm water. Many areas around the coke oven batteries were resurfaced. Storm water is routed to a dedicated storm water circuit. Mixing of storm water and process effluent is prevented. The current biological water treatment plant is not Use of irrigation circles will be discontinued. effective. A new biological water treatment plant will be constructed. This infrastructure is important in terms of Re-commissioning of the Coke Oven Battery, as additional effluent will be generated. The proper functioning and capacity of these project components are required for treatment and management of additional volumes of effluent. Current planning indicates that the ZED project will be implemented towards the end of Upgrades/improvements at the existing coke oven batteries A number of improvements at the coke oven batteries have recently been implemented, while a number are under investigations (see Table 3). Table 3: Improvements at the coke oven batteries Description Installation of gravel filters The use of recoverable effluent as quench make-up is being investigated. An effluent tank has been installed. The tar separation facility has been upgraded Drains have been traced and cleaned. Comment Increases the availability of the gas treatment plant, as less tar is carried over. The project is planned to be commissioned in October Quench tower emission will be reduced, should the use of recoverable effluent be feasible. Ensures maximum recycling of contaminated effluent. Reduces the volume of non-recoverable effluent by 35m³/h. Non-recoverable effluent flow has been reduced by 18m³/h. 4 THE PROPOSED PROJECT 4.1 Location is situated to the north east of Newcastle and north west of Madadeni. (refer to Figure 2). The Buffalo river is on the northern border of the site, while the Ngagane river crosses through the southern part of the site. Access to the is via Iscor road, which intersects with the N11. The site is typical of a heavy industrial area, with a number of operational plants and transport and other infrastructure. The coke oven battery, which is proposed to be re-commissioned is situated on the southern part of the site. Before presenting the components of the proposed project, it is necessary to describe the production of coke. 4.2 Overview of coking process Mining of coal The production of coke starts with mining of coal. Both good quality hard coking coal and semi soft coking coal is required. The coal is brought to the surface and hard coking coal is transported by ship and rail from overseas, while semi soft coking coal is transported by rail from inland mines (e.g. Grootegeluk mine in Lephalale) Stockpiling and preparation Once coal arrives at the coke ovens, it is stockpiled in dedicated areas (refer to Figure 3). Before the baking process, different grades of coal are blended to ensure production of good quality coke. Blended coal is crushed and stored in a battery top storage bunker (1) above the coke ovens. 4

5 North Mills Figure 1: Location of north east of Newcastle and north west of Madadeni. Map of with location of coke oven batteries indicated. Waste Site Coke Ovens Sinter Plant Mill Scale Steel Plant Blast Furnace BOF Slag Ngagane River Buffalo River GSB Dump BF Slag 5

6 4.2.3 Conversion of coal to coke Coal is released from the battery top storage bunker into a charge car (2). The charge car moves on top of the coke battery and charges or fills the different chambers (3) of the coke oven through charge holes. The temperature of the coke oven chambers are kept at between 1200 C and C. The baking process starts immediately after charging of coke oven chambers and sealing of the ovens. After ~19 hours of baking in the absence of air, the center of the coal has reached C and the coal has been converted to coke. Coke is pushed out of the oven with the steel ram of a pusher machine into a coke quench car (4). During the baking of the coal to coke, volatile constituents in coal are released as a gas and are extracted through the batteries collecting mains. The raw coke oven gas is then cleaned through various processes and reused as a fuel at the Coke Ovens and various other processes on the Newcastle Works site Coke quenching The coke quench car transports the hot coke to a quenching tower (5), where large volumes of water is released over the coke to cool it down. After quenching, the coke is stored in silo s and on stockpiles (6) from where it is transported via conveyors, screened and transported to the blast furnace at the or to customers in North West Province, Mpumalanga and KwaZulu Natal. Inputs Coal (by truck, ship and rail) Energy (coke oven gas and electricity) Water (from recycling) Steam, compressed air Coal stockpiling, blending & crushing Coal in battery top storage bunker 1 2 Charge car Stack Coke quench tower 5 Coke oven battery 6 Coke storage (stockpiles and silo s) Material flow 4 Coke quench car Outputs Metallurgical coke to blast furnace (by conveyor and/or truck) Ferro-alloy coke to customers (by truck and rail) Coke oven gas to gas treatment plant (firing of coke oven batteries & flaring) Ammonium sulphate (sold to customers) Tar (processed in Vanderbijlpark) Elemental sulphur (sold to customers) Atmospheric emissions 3 Oven chamber Refractory wall Waste materials Air emissions Dust, Volatile organic compounds (VOC s), SO 2, NO x and others Liquid effluent Storm water, bleed-off stream from gas cleaning Solid waste - Tar sludge, sludge, steel and asbestos rope (during repair) Figure 2: Schematic diagram of the coke production process, indicating inputs, outputs and waste materials Ancillary operations: Coke oven gas and water treatment It is necessary to provide a description of the coke oven gas cleaning process and water circuit in the coke battery at Newcastle to indicate sources of liquid effluent and solid waste generation. The schematic process flow is presented in Figure 4. 6

7 Gas cleaning/treatment plant Napthalene circuit Coke battery Spray with coal water Tar sludge (possible recycling) Ammonia liquor storage tank Tar (product) Water H 2 S/NH 3 still Crude benzol (product) Pitch to Newcastle Works waste site Sludge to Newcastle Works Waste site Biological water treatment plant Reverse osmosis facility Water 160 m 3 /hr Ammonium sulphate plant Elemental sulphur plant H 2 S/NH 3 vapour Recycled to various plant in Ammonium sulphate (product) Sulphur (product) Clean coke oven gas to coke battery and other plants Gaseous flow Water and solids flow Water handling / treatment facilities Water Effluent Plant Coke oven interceptor Figure 3: Schematic presentation of the coke oven gas cleaning process and water circuit Gas cleaning plant The following description is a summary of a number of processes that treat gas and water in the gas cleaning plant. Hot crude coke oven gas, which forms as a result of heating of coal in the coke ovens, is cooled down from 800 C to 80 C by spraying it with coal water. When the crude coke oven gas cools down, a mixture of high boiling compounds is separated from the water and gas to give tar sludge that is disposed of at the waste site and tar, a product which is transported to ArcelorMittal South Africa, Vanderbijlpark Works for processing into saleable products. Coal water from the gas cleaning plant is then routed to an ammonia liquor storage tank, while ammonia and hydrogen sulphide is scrubbed form the coke oven gas. The coke oven gas is directed to the naphthalene circuit Napthalene circuit After further treatment in the naphthalene circuit the clean coke oven gas is routed to the coke battery and other operations on site as energy source. Crude benzol, which contains a number of useful compounds, is transported to the Vanderbijlpark Works for further purification. Pitch is disposed of at the waste site Elemental sulphur plant Coal water from the ammonia liquor storage tank is led to the H 2S-ammonia still where hydrogen sulphide and ammonia are distilled out of the coal water. The hydrogen sulphide and ammonia are directed to the sulphur plant, and ammonium sulphate where elemental sulphur and ammonium sulphate is produced for sale to customers Biological water treatment and Reverse Osmosis Plant After removal of hydrogen sulphide and ammonia in the H 2S/ammonia still, all water from the coke ovens operations is directed to a tar/water separator, which removes small quantities of tar and oil. Water leaving the tar/water separator is treated in a biological water treatment plant, where a combination of different micro-organisms consumes ammonia and cyanides, while changing the chemical and biological oxygen demand. Water from the biological treatment plant is at present directed to evaporation ponds, where it is stored and water quality tested. Water is irrigated from the evaporation ponds onto irrigation circles to prevent overflow. Following the implementation of the ZED project, water will be routed from the biological treatment plant to the reverse osmosis facility, from where it will be recycled to different parts of the operation. After commissioning of the Reverse Osmosis plant irrigation circles will not be employed anymore. 7

8 4.3 Components of the Proposed Re-commissioning An investigation of the coke oven battery, which was decommissioned in 1983, indicated that it is in a suitable condition for re-commissioning. The following changes will be required to comply with operational specifications, as well as the requirements of environmental legislation: Coke oven battery Minor repairs to the refractories (specialised bricks) of the coke oven battery will be necessary and approximately 10% of the refractories will be replaced. Structural steel, piping and electronics will be refitted. Coke oven battery doors and door seals will be replaced with new doors and knife blade seals, which is updated technology. The loading and pushing machines will be replaced and coke-side de-dusting equipment will be included to reduce atmospheric emissions. The charge car and battery top will be modified to allow for smokeless charging. The use of steam will be discontinued on the battery collecting mains and additional coal water from the increased volume of coal in the coking process will be used in the battery collecting mains. The re-commissioned coke oven battery will share an existing stack with an existing coke oven battery. An existing flare stack south of the coke oven batteries will be repaired to allow flaring of additional gas that will be generated by the re-commissioned coke oven battery Sump at quench tower Sumps at the quench towers are used to collect water from a storm water interceptor to allow for settling of fine coke (coke breeze) from the water. Coke breeze is re-introduced to the coke oven batteries and water is re-used as quench water. The capacity of the sump at the northern quench tower may need to be increased to handle larger volumes of water Coal storage area The coal storage area needs to be expanded for storage of an additional ton of coal. The materials handling system will be changed to handle larger volumes of coke and coal Gas treatment plant Components of the existing gas treatment plant will be expanded to provide capacity for increased gas volumes. These include an additional line to remove ammonia and hydrogen sulphide from coal water in the gas treatment plant. 4.4 Project schedule Repairs, upgrades, expansion and pre-heating of the coke oven battery are proposed to start towards the end of 2011 and take place over some 14 months. Re-commissioning is planned for Re-commissioning will involve heating the coke oven battery over some 72 days to the operating temperature of between and C. 4.5 Environmental aspects of coke production The proposed Re-commissioning of the Coke Oven Battery has been analysed and a summary of the environmental aspects, associated with the proposed project is provided in Table 5. The project description and these aspects will be employed as basis for the impact assessment. Figures, such as atmospheric emissions, waste volumes and the increase in truck transport on roads, will be quantified. 4.6 Alternatives The following alternatives have been considered during the formulation of the project and the first stages of the EIA: Location ArcelorMittal South Africa operates coke oven batteries in Newcastle, Vanderbijlpark and Pretoria. There are however not a coke oven battery at these locations that is in a similar condition that can be repaired and refitted for recommissioning within the same time period. 8

9 4.6.2 Technology It is believed that it may be possible to re-commission the coke oven battery and comply with emission standards for existing coke oven batteries 4 with current technology. A comparison of current technology on the coke oven battery with updated technology is presented in Table 4. Table 4: Activities required for coke production presented with current and proposed technology and emissions Activity Charging Proposed technology 1 Controlled Charging (simultaneous charging through 4 charge holes, including gas tight connections between charge car and oven) Pneumatically sealed ascension pipes (improved sealing at vent of transfer pipe from coke oven to gas cleaning plant) Current technology 150 g PM 2 /t coke 65 t/a 93 g PM/t coke 41 t/a Aspects Updated technology 15 g PM/t coke 7 t/a <1 g/t coke < 1 t/a Coking Firing Pushing Charge hole lids and roof insulation (charge holes on top of coke ovens) Spring loaded flexible oven doors (doors allow for movement in refractory during coking and seals better) Desulphurised Coke Oven Gas (Sulphur content of coke oven gas will be reduced through improved scrubbing) Staged air combustion (lower flame temperature during firing, less emissions to air) Waste gas recycling (improved temperature control) Firing control (measurements and adjustment of fuel and air composition to improve temperature control) Dust removal facilities (implementation of bag filters and hood for dust extraction) 1 Technology Review, Tim Knights, PM particulate matter 3g/t coke 1 t/a 10.5 g/t coke SO 2 >1350 kg/d NO x >600 g/t coke >1350 kg/d 400 g PM/t coke 174 t/a <3 g/t coke <1 t/a <2 g/t coke Huge visual improvement SO 2 < 1000 kg/d NO x g/t coke <840 kg/d <20 g PM/t coke 9 t/a ArcelorMittal South Africa made a decision to implement updated technology in order to comply with emission standards for new plants 2. It should be noted that implementation of advanced technology needs to be combined with rigorous operational discipline to achieve maximum environmental performance over the lifespan of a coke battery Other alternatives Given the existing coke oven battery, no alternatives have been identified in terms of type of activity, design and layout. The no-go alternative will be presented in the Draft Environmental Impact Report (EIR). 4 NEM: Air Quality Act, GN No 248, 31 March

10 Table 5: Summary of environmental aspects associated with the proposed Re-commissioning of the Coke Oven Battery. Aspect category Aspect Source / Comment Resource use Coal use Hard coking coal Increase in imported coal via Richards Bay. Coal supply from Makhado mine (~ 60 km from Musina, Limpopo Province) Soft coking coal Increase in coal supply from Groote Geluk mine (Lephalale area, Limpopo Province) Water use Raw water No additional raw water will be required Potable water No additional potable water Energy Electricity Additional Eskom electricity Steam Additional steam, generated in existing boilers on site Gas An additional volume of m 3 of gas/hr will be produced, resulting in some m 3 /hr of both blast furnace gas and coke oven gas being flared while the feasibility of an electricity generation plant is being investigated. Land The existing coke oven battery is situated towards the east of the 3 operational coke oven batteries within the. Socio-economics and infrastructure Waste Employment opportunities Permanent/temporary workers Some 400 temporary and 18 permanent workers at the height of construction Transport Rail Additional transport of coal Additional transport of ton ferro-alloy coke. Road Additional transport of ferro-alloy coke at 23 tons/truck. The implication is some truck loads of coke. Some coal may also have to be transported by road, should there not be sufficient capacity to accommodate it on rail. Atmospheric emissions Coke oven stacks Height: 110m Quench towers (two) Height 18m Increase in particulate matter (dust) emissions. Emissions to be modelled by the air quality specialist. Increase in sulphur dioxide (SO 2) emissions. Emissions to be modelled by the air quality specialist. Increased in nitrogen oxides (NO x) emissions. Emissions to be modelled by the air quality specialist. Increase in particulate matter (dust) emissions. Emissions to be modelled by the air quality specialist. Fugitive emissions Increase in volatile organic compounds (e.g. poly-aromatic hydrocarbons, dioxins), carbon monoxide emissions. Included in assessment by air quality specialist. Wind-blown dust from stockpiled material. Included in assessment by air quality specialist. Waste water Process water Water content of coal, which will be processed in the gas treatment plant and routed to the effluent treatment plant and biological treatment plant. The additional volume of water from coal baked in the re-commissioned coke oven battery will replace use of steam in reduction of emissions during charging of the coke oven batteries. Solid waste Tar sludge (1.1 The additional volume of tar sludge from the gas treatment plant will be re-introduced into the coke oven batteries. kg/ton of coal used) Sludge Additional volume to hazardous waste site Refractory waste An estimated ton of refractory bricks, which consists of silica, will be removed from the battery top and be sold. Asbestos rope Approximately m of asbestos rope will be removed from the de-commissioned coke oven battery doors according to specifications of the Occupational Health and Safety Act and be disposed of at the licensed hazardous waste site. 10