Waste Management Solutions Worldwide – Since 1975

Modeling of Solid Waste Systems

CalRecovery has developed and used a number of highly specialized mathematical models and computer programs to analyze various types of collection, processing, transfer and transport, and disposal alternatives for mixed (residual) solid waste, recyclables, and organic materials. These models use fundamental variables and parameters so that they can be used to analyze a multitude of solid waste programs under various operational and financial conditions in any location. CalRecovery has employed the models to analyze the technical and financial implications of alternative collection, processing, and disposal systems for various governmental and private sector clients, including those in the states of California, New York, Minnesota, Missouri, and Washington. The models have 30 years of development history and calibration. Our capabilities include the following:

  • analytical spreadsheets that compile and sort diverted and disposed waste quantities by type, source, and program
  • lifecycle economic analyses for landfill development and operation, including capital expense, operating costs, and costs for closure and post-closure site maintenance
  • analysis of collection systems for mixed waste, recyclables, and green waste — residential and commercial sectors, single- and multi-compartment bodies; diesel and alternative vehicle fuels; mass balance and technical performance; capital and operating costs (for example, the collection model can be used to estimate total number vehicles required to collect materials, miles driven, based on local conditions in the area)
  • process engineering analyses of waste and materials processing systems, including as a function of waste composition and system configuration the following outputs: mass and energy balances on each unit operation; yield and quality of process streams; and ultimate, proximate, and trace element analyses of all process streams
  • materials processing economic analyses based on system configuration, including breakdowns of expenditures for capital equipment, operation, and maintenance
  • rate analysis — integrated analysis using collection and processing model assumptions and financial results; estimation of migration of container sizes based on local conditions and incentives at the generator level; calculation of unit costs, e.g., $/household, $/ton, etc.
  • financial analyses of composting systems for a number of processing configurations and composting technologies, including turned windrow, static piles, and two enclosed vessel systems
  • process engineering analyses of thermal conversion systems, including mass and energy balances, overall thermal efficiencies, and exhaust gas and process residue characteristics