CMA

29 As a basic rule, waste accepted must give an added – value for the cement kiln • Calorific value from the organic part • Material value from the mineral part Many substances, particularly those of low calorific value, contain a significant proportion of incombustible substance(s), while inorganic substances are used as a combination of high and low calorific value raw material. In some cases, kilns can be used for the safe disposal of hazardous waste such as obsolete pesticides, PCB or outdated pharmaceutical products, which may not have appropriate material or energy value, but can be disposed in cement kiln without impacting the product quality. However, for this type of treatment, regulatory authorities and cement plant operators must come to individual agreements and standards on a case by case basis in consultation with CPCB. FEEDING OF MATERIALS FOR CO PROCESSING Different feed points can be used to insert the co processing materials into the cement production process. The most common ones are: • The main burner at the rotary kiln outlet end. • The rotary kiln inlet end. • The pre calciner. • The mid kiln (for long dry and wet kilns) Appropriate feed points have to be selected according to the physical, chemical and toxicological characteristics of the substances, if relevant, used. Wastes of high calorific value have to be always fed into the high temperature combustion zones of the kiln system. Such wastes containing stable toxic components should be fed to the main burner to ensure complete combustion in the high temperature and long retention time. Alternative raw materials containing components that can be volatilized at low temperatures (for example, hydrocarbons) have to be fed into the high temperature zones of the kiln system. Feeding of alternative raw materials containing volatile (organic and inorganic) components to the kiln via the normal raw meal supply should be avoided unless it has been demonstrated by trial runs in the kiln that there is no undesired emission from the stack. IISPL Ajmer, a company founded by Late “Smt. K.K. Sharma” who was renowned Chemical Engineer & Process Expert, has recently developed a product called Arrest Master AFR- Liquid AFR Charging Nozzle, for effective combustion of Liquid AFR & Hazardous Waste. IISPL has developed the above product after extensive research at its highly efficient, design & manufacturing facility. In conventionally used systems a lot of compressed air consumption is there, but Arrest Master AFR Charging Nozzle is a special design Nozzle which uses less than 10 CFM of compressed air to atomize the AFR Liquid. It has been designed to give trouble free & maintenance free service as there is no moving part in it. EXPERIMENT WORK • We requested the management of ABC Cement Limited, Rajasthan for our Pilot Project to install very first of our Nozzle system & got approval in July- 2020. At ABC Limited Plant, they are having two categories of Liquid AFR material sourced from different facilities in Gujarat having difference in Calorific Values in range as below  High-CV Waste: 2800-6000 Kcal/Kg  Low-CV Waste: 0 Kcal/Kg • The ABC Cement Limited, plant had consumption of Liquid AFR before installation of our nozzle system around 0.5 KL/Hr for a 3000-4000 TPD Plant having Five Stage, Double String Preheater. The problems faced due to Liquid AFR Usage were  Unstable & Disturbed Operation  CO Generation  Coating problem due to incomplete combustion & material dripping  Refractory Damage & Wear.  Frequent Jamming of Nozzle  Life of Nozzle is Less • Negative Cost of Liquid AFR is 2200-3000 Rs/KL for Low CV Material. • For High CV Material Transportation cost of Rs 500-600 Rs/KL is in Plant Scope. OBESRVATIONS, DISCUSSIONS, FURTHER IMPROVEMENT IN DESIGN & RESULTS After the very first installation of our Nozzle system in July- 2020 at ABC Limited Plant. The Nozzle Design version being V 1.0 installed and its performance characteristics were noted with the joint efforts of our engineers by conducting timely visits & regular monitoring by Plant Team. The following were the observations