The Tyre Pyrolysis plant is a latest technology and widely accepted throughout the modern world. According to a recent study, increasing industrialization and motorization has led to a significant rise in demand of petroleum products. As these are non-renewable resources, it is difficult to predict availability of these resources in the future, resulting in uncertainty in its supply and price. This is impacting growing economies like Pakistan, which is importing 80% of the total demand of the petroleum products. Many alternate fuels like Biodiesel, LPG (Liquefied Petroleum Gas), CNG (Compressed Natural Gas) and Alcohols/Ethnol are being used nowadays by different vehicles. Biomass and coal are being used as fuel for power plants for which EPAs are also according environmental approvals. In this context Pyrolysis of Scrap tyres are being used effectively to produce oil, thereby solving the problem of waste tyre disposal. The aforementioned process involves the most environment-friendly use of tyres as it does not emit polluting toxic fumes, which are released when tyres are burnt openly or directly for heating in furnaces or kilns etc. Furthermore, tyre oil replaces, use of coal or wood or even tyres as burning fuel in small industries. This oil is now being widely used by Steel Re-Rolling Mills and other industries. It is also a health conducive process as better and continuous disposal of tyres in Punjab and Sindh has reduced breeding grounds of dengue mosquitoes.
Pyrolysis is a Thermochemical decomposition of organic material at elevated temperature in the absence of oxygen. Pyrolysis typically occurs under pressure and at operating temperatures about 430°C in a batch process system. The waste tyres are stacked in a steel reactor of approx. 8 ft. diameter and 20 ft. length and then sealed. The cylinder/reactor is initially heated by means of oil/wood under controlled condition of temperature and pressure. The process brings about molecular restructuring of rubber and converts into vapor and gases. These vapors and gases come into separator where heavy oil fraction is separated from gases and the gases are passed through the series of heat exchangers to condense the vapor into liquid form called tyre pyrolysis oil (40 to 45%) by means of re-circulated water from cooling tower and is collected into the storage tank. Non-condensable gases, also called pyro gases (about 10%), are used for heating the reactor in place of oil/wood initially used for heating purpose as per the requirement. During the process carbon black (30 to 35%) and steel wires (10 to 15%) are also generated, being pulled out of reactor to be sold into the open market. Pyrolysis of scrap tyres produces oil that can be used as liquid fuels for industrial furnaces, foundries and boilers in power plants due to their higher calorific value, low ash, residual carbon and sulphur content. In the 10th Meeting of the Parties in Columbia 17-21 October 2011 the “Revised Technical Guidelines for the environmentally sound management of used and waste pneumatic tyres” were adopted. Mr Zaigham Abbas, Deputy Director, Federal Ministry of Climate Change (MOCC) represented Pakistan in the said meeting. The guidelines cover almost all the aspects including components of tyres, the possible harmful effects on human health and environment, the various methods of handling, storage and disposal etc, and the possible positive and negative effects of various disposal processes on environment and remedial measures. A perusal of the stated guidelines shows that “waste management hierarchy should apply as a priority order in waste prevention and management, legislation and policy to avoid undesirable impacts on the environmental and human health.
The Punjab Environment Tribunal had already declared the Pyrolysis as “Green Technology” in pursuance of “BASEL CONVENTION 2011” of which Government of Pakistan was also a signatory. Revised Technical Guidelines for the Environmentally Sound Management of Used and Waste Pneumatic Tyres were formulated under the said Basel Convention. Besides, the process of Pyrolysis is recognized as one of the only three environmentally suitable processes by the Basel Convention, held under the aegis of UNEP. Moreover the import of tyres for the purpose of pyrolysis gasoline is neither prohibited in terms of Import Policy Order 2016 nor is there any restriction under any other law including Petroleum Act, 1934 read with Petroleum Rules, 1937 or under Pakistan Petroleum (Refining, Blending and Marketing) Rules, 1971. Moreover, OGRA has recognized the pyrolysis oil as a fuel vides its letter No. OGRA-OIL-19(9)/2006 dated 24-7-2013. That it is also a well-established law, by way of Judicial Order, which was subsequently reported in 2015 CLD 1079, that the Pyrolysis Plants support sustainability and are considered to be environmentally sound and socially responsible having a long term community value and they help reduce waste problem by converting waste into material resources and energy. The material and energy produced by these projects can be utilized and made available for the coming generations. These projects also reduce Greenhouse Gas (GHG) emissions and help the Global movement to solve the climate crisis.
The pyrolysis state-of-art process plants work in closed loops and there is hardly any emission of concern from the plant if proper mitigation and housekeeping measures are implemented. The Basel Convention and WTO rules also consider recycling of scrap tyres as a better option than their use as tyre derived fuel. Additionally, the government of Pakistan has adopted the policy of sustainable development, use of natural resources scarcely and to use indigenous coal, biomass in power plants to reduce reliance upon imported oil and to get economic benefits for the country, according to which the environmental assessment provides a means for promoting economic development which is environmentally sustainable and the use of resources by present generations while protecting the interests of future generations, for example avoiding over-exploitation of renewable resources, minimizing waste, leading to cleaner production.