The government is likely to allow the cement industry to use 'Tyre Derived Fuel' (TDF), which is a mix of about 80-88 percent carbon and oxygen, official sources told Business Recorder.
Pakistan has 29 cement plants with total installed capacity of 44 million tons. The shortage of natural gas and increasing cost of oil and coal has adversely affected cement production in the country.
The cement entrepreneurs are exploring different venues to supplement their fuel requirement for bringing down their cost of production. One of the options for them is to use certain percentage of old tyres, in shredded form, as fuel, as being practised in other countries. A number of cement units have approached the federal and provincial environmental protection agencies for issuance of consent under local, national and international obligations for import, processing and use of TDF.
Sources said that the objective of these guidelines is how to use TDF as supplementary fuel in cement manufacturing and prescribed procedures for monitoring of emissions.
These guidelines are reference document for using TDF in cement industry whether imported or local and owned by public or private sectors. These guidelines provide the minimum requirements that a cement industry should meet.
The following definitions shall be based in these guidelines, unless there is anything repugnant in subject context or contrary to the Pakistan Environmental Protection Act, 1997, rules, regulation and standards made thereunder.
A) "Authorised officer" means an officer authorised by the Federal or Provincial Government for the purposes of these Guidelines.
b) "certified laboratory" means any laboratory certified under the National Environmental Quality Standards (Certification of Environmental Laboratories) Regulations, 2000.
c) "consignment" means a batch of TDF procured under a purchase order;
d) DNA means 'designated national authority'.
e) "pollution control device" means a device installed at cement kiln to filter or remove particulate matter and 'other emissions' which may include electrostatic precipitator or a bag-house filter.
f) "storage area" means a site where TDF is accumulated within a structure that is not completely enclosed; and which comply with guidelines and relevant local/national laws.
g) 'TDF'means a fuel that is derived from end of life scrap tyres by completely shredding/cutting them into pieces for use as supplemental fuel.
The import in the country is governed by the Import Policy as announced by the Federal Government from time to time and 'the international conventions and protocols to which Pakistan is a party'.
No cement unit is allowed to import, or use, TDF without obtaining consent from the concerned Environmental Protection Agency (EPA) and the Designated National Authority (DNA) of the related international convention/protocol. The following criteria and standards will apply to award consent to the cement unit desirous to import or use TDF in the country:
A clean TDF is composed of about 80-88 percent of carbon and oxygen, which accounts for its rapid combustion and relatively high heating value in the range of 7000-8000 kcal/kg. Cement unit will procure clean, properly sized (2 inches), high-energy-content tyre derived fuel as far as possible. Each consignment of TDF will be accompanied by a certificate from DNA of the exporting country, verifying that the consignment of TDF does not contain or is contaminated with hazardous substances or wastes as defined in Annexure IX of the Basel Convention. The procedures laid down in the Basel Convention will be followed in the import of TDF. The Authorised Officer of EPA will check quality of TDF as and when deems necessary.
The transportation and storage arrangements for TDF will be done in accordance with the Environment Management Plan. In addition, the cement industry should modify its fire fighting plan and procedure to include and respond to the potential fire risks and hazards associated with transportation storage, and usage of TDF. Special attention should be given to the fire protection measures on the feeding end of the cement kiln.
Normally, a cement unit utilises 15-30 percent TDF of the total heat input. The exact maximum quantity shall be determined after carrying out emission tests at individual unit through third party under supervision of concerned EPA. No cement unit will be allowed to use TDF quantity beyond the limit set out. However, cement units can be allowed to use a greater proportion of TDF provided they improve performance of pollution control system and after re-checking emission levels by concerned EPA.
Each cement factory will get its feeding system and pollution control technologies/equipment inspected before the use of TDF as fuel. For this purpose, a joint team comprising of the representatives of DNA and concerned EPA, within 15 working days from the receipt of inspection request, will assess the facilities of the cement unit and will witness the test trial of use of TDF.
Uncontrolled and disproportionate feeding of TDF could lead to toxic emission of gases from kiln stack. There is need to properly install automatic TDF feeding/weighing system and maintain record. In case of higher concentrations than the emission limits mentioned in the Guidelines are observed due to tripping or malfunctioning of pollution control device of the kiln, the TDF feeding system should automatically stop immediately.
Two operating conditions viz, operating temperature and retention time, are of utmost importance for avoiding production of dioxin and furan. Operating temperature in cement kiln, which is over 1550°C, and retention time of 3 to 6 seconds in above 1200°C, is well suited for the safe and efficient consumption of TDF.
The level of emissions from any furnace / kiln is highly dependent on the way it is operated and process is controlled. In general, emissions are likely to increase when operated in unstable conditions. Emissions being released from the burning of TDF in uncontrolled and controlled conditions are different. In the former case, TDF burning, especially at low temperatures, causes generation of highly toxic gases and compounds like Poly-aromatic hydrocarbons, dioxin/furan, hydrogen chloride, benzene, polychlorinated biphenyls (PCBs). Metals such as arsenic, cadmium, nickel, zinc, mercury, chromium, and vanadium are also emitted. Exposure to emissions from tyre burning in uncontrolled conditions could cause irritation of skin, eyes, and, mucous membrane, central nervous system, depression, respiratory disorders and cancer.
In Pakistan, almost all cement units are equipped with some kind of anti-pollution devices to control emission of gases and particulate matter. The majority of the cement units are fitted with electrostatic precipitators (EPs). Some units frequently come across tripping or breakdown of Eps, causing "excessive emission of kiln flue gases and particles. Under this condition, use of TDF as fuel would allow free emission of toxic gases. Much emphasis, therefore, should be given on performance of pollution control devices while using TDF as fuel. Besides, electrostatic precipitators, scrubbers should be used where required to clean out hazardous gases--Benzene, Polycyclic Aromatic Hydrocarbons (PAHs) or Ploy Chlorinate Biphenyl (PCB). All anti-pollution devices should be kept in good operating condition.
It is desirable that cement industry using TDF should have in-house capacity for measuring levels of conventional pollutants like PM, CO, NOx, SO2, THC using reliable emission analysers. The staff should be trained to independently check emission of heavy metals as prescribed in the above standards. In absence of the facility, the services of EPAs or approved/laboratories certified under Certification of Environmental Laboratories Regulations 2000 should be acquired for monitoring the emission, including heavy metals.
Every cement unit burning TDF will be registered under self-monitoring and reporting tool (SMART) with concerned EPA. Cement industry will monitor the level of PM, CO, NOx, SO2 and THC using own reliable online emission analysers and maintain record and also report the same to the concerned EPA in accordance with the frequency mention in the table under heading "emission limits".
Cement industry will also include the following information and report to the concerned EPA on monthly basis; (i) quantity of TDF imported; (ii) quantity of TDF used; (iii) quantity of local TDF used[ and (iii) amount of coal/fuel used.
Cement industry desiring utilidation of TDF will prepare a detailed EMP and submit to the concerned EPA. The EMP will be prepared considering these Guidelines as well as the obligations under the prevailing environmental laws.
The management may invite public representatives and duly brief them about their plan for using TDF. The community should be educated on the pollution control measures while using TDF
