The problem of destruction of the liquid, mixed and moist wastes consists of the fact that they cannot be placed on the grates of regular furnaces for solid fuel as a result of the presence of liquids. The presence of solid particles, which immediately drive the sprayers, prevents the dispersion of wastes with the aid of the sprayers for combustion in suspension. Solid residue from the combustion is laid aside on the walls of the furnace and the fuel equipment, rapidly rendering them inoperable. Thus technically it is not possible to burn liquid, mixed and moist wastes without preliminary preparation, for example drying. Finely dispersed wastes, such, as silt from sumps, or fatty production oil wastes, never dry to the point when they can be burned as solid.
Abattoirs wastewaters that contain blood constitute serious environmental threat when drained away. In these latter days the offers to use special bacterial cultures for decomposition of such sewage waters were made. However in the course of bacterial decomposition process toxic and evil-smelling gases such as ammonia, sulphuretted hydrogen and RSH are exhaled. After process end in the residuum there are noxious substance: indole, skatole, cadaverine, putrescine and other substances that require utilization.
The proposed technology of thermo-chemical utilisation of liquid, mixed and moist wastes works in a following sequence: settling at elevated temperatures, separation, discharge of isolated water, dehydration of the remainder, pyrolysis of remainder, which obtains pyrolytic gas and solid residue, afterburning of solid residue and cleaning the waste gas.
Application of offered processing plant enables to solve the problem of utilisation of abattoirs wastewater.
Pyrolysis is the only reasonable method of disposal of abattoirs wastewater. Due to fact that a result of pyrolysis in special furnaces, decontaminated waters, clean gases and chark are formed. Combination of abattoirs wastewater with grease sewage waters enables to reduce fuel consumption for utilization.
The company has devolved an installation on the bases on the described technology, which can be personalised for the needs of each customer, depending on the chemical composition of the wastes to be recycled.
Performance characteristics of a sample device
• Productivity – 1 ton/hour.
• Fat containing in wastes for operation – no less than 15%.
• Exhaust into the atmosphere – 75 000 м3 /hour of СО2, N2 and Н2О mixture.
• Tar content in exhaust – no more than 0,001 mg/l.
• Sulfur oxides content in exhaust – not more 0,001 mg/l.
• Discharge of disinfected at 100 СО water into sewerage system – no more than 750l/hour.
• Residual fat content in overflow water – no more than 2000 mg/l.
• Suspended particles content in overflow water – no more than 2000 mg/l
• Chemical oxygen demand in overflow water – no more than 1000 mg/l.
• Fixed residue from waste burning-gasification- no more than 10 kg/hour. It can be used as a fertilizer.
• Overall dimensions of the device – not more than 10 X 2 Х 3m.
• Fully loaded mass of the device no more than 10 tons.
• Electric energy input – no more than 3 kW.
• Fuel consumption at start of the device (once) – 50 м3 of natural gas.
• Maintenance staff – 1 person.