Refinery's waste treatment services
Ecomed’s Refinery waste treatment service provides expertise and technology for the solutions to the following problems:
- Treatment of Fluids dregs from oil storage tanks
- Treatment of Semi-solid oil sludge from oil refinery process
- Treatment of Muds from softening of cooling waters
- Treatment of Hydrocarbon contaminated soils (production lagoons).
Treatment of semi-processed oil refinery products
Oily sludge resulting from oil refinery processes (API tanks, tank sludge, biological sludge from the treatment of oily sewage waste) are difficult products to manage due to their low fluidity and their high hydrocarbon content.
This kind of sludge, if not treated, due to its high oil content, can only be delivered as it is to treatment plants or to incineration. This solution has important costs and technical implications, due to the need to move a mass whose consistency is between pumpable and shovelable, which also is often be classified as hazardous for transport and, for handling. Moreover, in this way it will not be possible for the Customer to recover the hydrocarbon fraction from the sludge.
To meet this challenge, Ecomed has developed a system for the management of semi-processed products aimed at maximizing oil recovery while at the same time reducing the residual fraction of the treatment, to be sent for disposal off site.
The system used is divided into two phases:
- The treatment of semi-processed oil refinery products, which results in:
- liquid flow (composed of water and hydrocarbons), returned to the Customer for reintroduction into the refining cycle;
- a solid flow, which is classed as waste and sent for further stabilisation/solidification treatment;
- The treatment of solid waste, resulting in a semi-solid mass, suitable for safe transport for off site disposal.
The process applied consists of:
- dehydration treatment of semi-processed oil refinery products;
- stabilisation/solidification treatment of solids derived from the dehydration of semi-processed products.
The dehydration treatment includes:
- accumulating the sludge in a homogenization tank, where it is mixed and heated;
- supplying the sludge to the dehydration system through a single screw pump with variable capacity;
- the dosage on the line of appropriate polyelectrolyte selected for the typology of the sludge supplied and of the result required;
- phase separation through centrifugation of the conditioned sludge.
According to requirements and on the Customer’s request, the process can be optimised to obtain a drier panel but with higher oil content, rather than a panel with a slightly higher humidity after recovery of a higher percentage of oil.
The stabilisation/solidification treatment, can be carried out on the same line or on a specialised system. To be able to discharge the waste, stabilisation is carried out by mixing in water binders (lime or concrete) with the waste and additives which adsorb the oil residues (zeolites, urasites) and, if the panel needs to be sent for thermal treatment, organic amendants will be added (sawdust, coconut fibres). However, the system is sufficiently flexible to adapt the reagents used to various requirements without the need to modify the installation.
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