|Gossman Consulting, Inc|
See the Hazop review format GCI uses at: http://gcisolutions.com/GCINOTES898.htm
Portland Cement plants around the world as well as aggregate kilns and sulfuric acid furnaces operate commercial facilities to use hazardous waste fuel received from off site sources. Accidents at these facilities can and have had significant negative financial and community relations impacts as well as injury to plant personnel. A comprehensive facility operations review including a Hazop study can help to limit the potential for accidents and simultaneously point to improvements in operational efficiency and profitability.
In the course of operating a hazardous waste facility there are numerous hazards that must be dealt with in order to limit liabilities. These can include physical accidents, fires, explosions, electrical accidents and chemical exposure. A hazardous waste management facility is unique in industry relative to a number of these hazards because of the need to handle a wide variety of chemicals and chemical mixtures. It is no exaggeration that a hazardous waste operator will see more different chemicals in a month than a chemical plant operator sees in 10 years. This creates a situation where hazards such as chemical incompatibility and personnel exposure are far more complex than, for example, chemical production facilities. Yet, many chemical production facilities have far more comprehensive and complex programs to minimize these same risks.
The hazardous waste fuel industry is challenged to provide cost effective options for reusing as much hazardous waste as possible while maintaining compliance with increasingly complex regulations. Clearly that is not enough. The safe operation of these facilities is of paramount importance to all of those associated with and/or working in this industry. The liabilities associated with accidents are far too great to be ignored.
As an example of physical accidents, early in the history of the industry the greatest potential for an accident appeared to be falls from tanker trucks while climbing up or down to take samples. Most facilities have installed man ways and safety cables to address this hazard.
Examples of materials that have been problems at hazardous waste facilities include propylene glycol dinitrate, toluene diisocyanate, and vinyl acetate. Propylene glycol dinitrate is a shock sensitive, explosive fuel used in a stabilized mix to propel navy torpedoes and is commonly referred to as Otto Fuel after its inventor. It has appeared a number of times in the hazardous waste fuel market. It was at one time handled at a commercial incineration facility on the east coast where a number of employees were later determined to have permanent nerve damage as a result of exposure. Toluene diisocyanate is a water reactive compound used to make polyurethane. Even low levels of exposure can induce asthma like conditions and pneumonia in sensitive individuals. It has an extremely low allowable exposure limit as established by both OSHA and ACGIH (TWA 0.005 ppm). Vinyl acetate can have runaway polymerization reactions that generate considerable heat, when mixed with amines.
As a means to control these liabilities hazardous waste fuel facilities have used a number of tactics. In early programs it was not uncommon for a hazardous waste fuel facility located at a cement plant to take a very restricted list of waste codes, generally only D001, and F001 – F005. This was logically assumed to restrict wastes received to only those associated with selected solvents and flammable wastes that made good fuel. The difficulty came with the “derived from rule” and the desire on the part of marketing groups to expand the range of waste being handled to increase overall profitability of the programs.
Some facilities restricted themselves to only receiving from “blenders”, other TSDF facilities that would theoretically provide the needed blending expertise and quality control. Due to the competitive nature of the industry this seemed doomed to failure from the start. The variety of wastes necessarily handled at blending facilities means that the waste fuel coming from those blending facilities was generally far less consistent in composition than that from direct generators, even if specs such as heat content and chlorine were being met.
Generator certifications are another way of attempting to control various liabilities. While called for as part of an overall program, relying on generator supplied information to maintain regulatory compliance is not always accepted. Relying on generator supplied information alone to control actual hazards would not appear to sufficiently limit the facilities risk, based on industry experience.
Finally, there are Contingency Plans. Certainly a comprehensive and well maintained Contingency Plan is required both by the regulations and by common sense. That said contingency plans are one of those things that are implemented after the liability is incurred. It can certainly help to control the degree to which a particular incident impacts a facility but it is not an answer to the risks associated with dealing with hazardous waste. If the Contingency Plan has to be implemented then too little was done too late.
Ultimately a facility managing the use of hazardous waste fuels must address the inherent liabilities though comprehensive onsite professional management and control of the factors that are involved. Tools that can be used include:
Qualified personnel/training. Clearly the professional qualifications of the personnel managing the hazardous waste fuel operation are critical. This goes for the receiving and blending operation as well as the onsite laboratory. Without technically experienced personnel who understand the process and the chemistry, accidents will happen and opportunities to avoid accidents will be overlooked. Hazard communication and the subsequent use of appropriate personnel protective equipment by all employees based on this communication is a critical component in this part of the solution.
with appropriate levels of QA/QC. Comprehensive testing of
fuels both at the qualification stage and again upon receipt are
the safe operation of a facility. “If you don’t know what is in there
hurt you.” Continued advances in analytical technology make the use of
the technique of choice for knowing what is in hazardous waste fuel and
that knowledge to prevent situations that could result in chemical
workers or accidents involving chemical incompatibility. Current
testing at many facilities may
can meet regulatory requirements
meeting all operational needs to prevent improper mixing of waste
Decisions on waste fuel blending operations should be made in close
with the lab personnel trained to test and interpret the results of
Waste stream/compound review program. All hazardous waste fuel facilities receiving waste streams from off site have some form of prequalification program to identify and approve waste streams prior to receipt. The level to which the wastes are clearly identified and analyzed by the receiving facility varies considerably. The same can be said about the degree to which each waste stream is professionally scrutinized for health and safety issues. It is generally necessary to have a program that evaluates wastes on a compound-by-compound basis and sets up lists of acceptable and unacceptable compounds at various thresholds and under various operating/receiving conditions.
Administrative procedures. Finally, administrative procedures also play an important role in preventing hazards from becoming “accidents”. For example, there should be an administrative process for modifying and approving new or modified operating procedures as the needs of the facility and the waste market change. Appropriate administrative procedures supply a critical window for management to view and control the hazardous waste operation.
Hazop review of the entire facility and operation. Hazop reviews are a common practice both in Europe and in much of the chemical industry worldwide. They do not seem to be used much in the hazardous waste industry despite the significant contribution that they could make. Hazop reviews of exiting operations and potential changes to operations can help to prevent accidents by clearly identifying all of the risk factors in each operation, assigning the probability of occurrence and the outcome and then using that information to prepare procedures and recommendations for physical changes to the plant to limit liabilities. Hazop reviews are particularly helpful to management in prioritizing where to spend limited money to get the most bang for the buck in terms of liability limitation.
Job safety analysis. Along with but separate from Hazop reviews are job safety analyses. Whereas the Hazop review focuses on equipment and procedures a job safety review focuses on the worker performing a job and what is required to insure the safety of each worker at each job station or activity. Again, such reviews can point out critical tasks where extra training and attention may be required.