Inorganic hazardous contaminants

The examples given above and the work done in the last 10 years on phosphate washing demonstrate that phosphates are very powerful stabilizers of inorganic hazardous contaminants. Phosphate washing is very economical, and once the treated waste is disposed, because phosphates are common fertilizer components, the soil becomes enriched with phosphates. Hence, the entire disposal process is ecologically sound. 

The HAZCON solidification process is an ex situ technology for the immobilization of metals and inorganic hazardous wastes in wet or dry soil and sludges. The technology is a cement-based process in which the contaminated material is mixed with pozzolanic materials such as Portland cement, a patented additive called Chloranan, and water. The process is capable of treating solids, sludges, semisolids, or liquids. The mixture hardens into a cohesive mass that immobilizes heavy metals. 

In addition to the utility plant fly ash, one may also use volcanic fly ash, ash produced from burning municipal solid waste or any other combustion product that contains ash. The role of ash is also important in management of hazardous and radioactive waste because often such waste, if combustible, is incinerated to reduce its volume. The incinerated ash now is richer in inorganic hazardous components and needs to be stabilized. CBPC processes are ideal for stabilizing such ash because, phosphates are ideal materials to stabilize hazardous and radioactive contaminants, but as mentioned before, ash improves the physical and mechanical properties of the end products. Stabilization of such ashes is discussed in Chapters 16 and 17. 

Waste oil generated from lubricants and hydraulic fluids is one of the more commonly recycled materials. A significant fraction of the approximately 4 billion liters of waste oil produced annually in the United States is burned as fuel, much is recycled, and lesser quantities are disposed of as waste. The collection, recycling, treatment, and disposal of waste oil are all complicated by the fact that it comes from diverse, widely dispersed sources and contains several classes of potentially hazardous contaminants. These are divided between organic constituents (polycyclic aromatic hydrocarbons, chlorinated hydrocarbons) and inorganic constituents (aluminum, chromium, and iron from wear of metal parts barium and zinc from oil additives and formerly lead from leaded gasoline). 

Another hazard of compressed air is that it contains dust (organic and inorganic), water, and traces of hydrocarbons, which if they are not removed can cause excessive wear of tools or contamination of products. Morris writes, Those who use air for pneumatic tools or even paint spray seem to have an inbuilt resistance to any idea that the quality of their compressed air is of any serious consequence. The fact that it transmits concentrated quantities of abrasive particles and water into the finely machined orifices and cylinders of their tools seems to pass them by [12]. 

Another class of environmentally hazardous projects comprises finished stores of toxic, explosive, and flammable substances. In Ukraine, it comprises depositaries of benzene, petroleum, and oil products, ammonia, inorganic acids, rubber resin, pesticides, mineral fertilizers, and many other materials. The quantities of substances kept in those stores amount to tens and hundreds of tons. Many of them are situated near beds of potable water bodies. Besides being environmentally hazardous, they present attractive targets for terrorist acts, since in case of their damage the chemical contamination of the environment may spread over vast territories and water areas creating an extremely dangerous situation for the population. 

In addition to gasoline, CFC, and so on, various other organic and inorganic compounds such as heavy metals, sulfides, and cyanides on the USEPA Priority Pollutants List, and subject to various water quality criteria, guidelines, etc., when released can also contaminate the soil. The contaminated soil then becomes a hazardous solid waste which must be properly disposed of [63-86]. 

Arsenic is an ancient and well-known hazard and, along with lead and mercury, is an important environmental contaminant. The inorganic form is far more toxic than organic arsenic, which is commonly found in seafood. Arsenic-contaminated drinking water is a worldwide problem that affects millions of people. Human exposure also occurs from arsenic-treated lumber. 

The technology is commercially available and has been successfully applied for full-scale treatment and remediation of organic and inorganic contaminated material occurring at hazardous waste sites and within bays, harbors, and river areas. Bergmann USA was closed for business in 1998. However, the soil/sediment washing technology is still available from their parent company, Linatex, Inc. 

The PO WW ER system was developed by Wheelabrator Clean Air Systems, Inc., a subsidiary of U.S. Filter Corporation, to reduce the volume of aqueous waste and catalytically oxidize volatile contaminants. PO WW ER is used to treat complex industrial and hazardous wastewaters containing mixtures of organic, inorganic, and radioactive contaminants. This proprietary, commercial technology combines evaporation with catalytic oxidation to concentrate and remove contaminants, producing a high-quality product water. 

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