FR2762313A1 - Treating domestic waste, sludge and fat for fertiliser production - Google Patents

Abstract

Treating domestic waste, sludge and fat from a purification process comprises mixing and homogenising 60% domestic waste, 20% sludge and fats and 20% quicklime in a mixing tank (5) using an endless screw in tank until the temperature reaches 250-300 deg C and material is dry. It is then optionally ground. Preferably, before mixing the domestic waste is treated to remove metals (3) and ground to a particle size of 8-10 cm. The quicklime is in the form of a powder or small granules.

Description

- DESCRIPTION
The present invention relates to an industrial process and structure for treating household waste, sewage sludge and grease which make it possible to obtain an industrial substitute fuel, an organo-calcic amendment, an insulating material.

- THE PROCESS
The process uses crushed, de-ironed household waste, sewage sludge and grease and quicklime in powder or fine granules which allow a physicochemical reaction of dehydration and oxidation, under elevation of temperature and stabilization - reassuring products.

Its implementation is carried out in an industrial manufacturing unit; the mixture is homogenized in a pit and the emissions caused at the time of dehydration are sucked on an air washer which guarantees all releases to the atmosphere.

PROCESSING MODE - Preparation of incoming products: upon arrival of the collection vehicles, the raw household waste is dumped into a receiving pit. A brief manual sorting allows to extract some undesirable elements in order to control the incoming metals (iron, lead, zinc, chromium, copper, mercury ...)
They are then conveyed by conveyor belt to the crusher n "I (hammer mill) - fitted with undercarriage by magnetization and which makes it possible to obtain products with a particle size of approximately 8 to 10 cm which will be discharged into the pit reception.

SEWAGE SLUDGE AND GREASE
They are either collected or transported on the unit by specialized vehicles, stored in sealed tanks and then incorporated into the pit by pumping.

- THE LIVE LIME REAGENT n is in the form of powder or small granules. It is stored and incorporated into the brewing pit using a grain screw.

PREPARATION AND REACTION OF THE ELEMENTS IMPLEMENTED
The elements are used in the brewing pit fitted with an endless screw in the following proportions:
Household waste 60%.

 -Buds and fats 20%.

 Quick lime 20%.

The elements are mixed in a homogeneous way then taken out of the pit.

PIIYSICO-CIFIMIQUE REACTION
In contact with wet elements, quicklime will allow a significant rise in temperatures - (from 250 to 3000) causing dehydration without flame and without oxygen after eight hours the elements are stabilized while guaranteeing a product whose calorific value reaches approximately 3,500 PCI

The dehydrated product is then sent to the nOII mill under vacuum and under vacuum and after grinding, a powdery product is obtained, or a product ready to be capped for agricultural use.

During dehydration, the volume and weight decreased by 40% and the product obtained had a density of 0.5.

THE IM) USTRY TREATMENT UNIT
The industrial processing unit with an annual capacity of 20,000 tonnes is made up
- the following:
An enclosed industrial building of 2,500 m2.

An O.M.

A manual sorting table.

A hammer mill "I" fitted with a railing assembly.

- A brewing pit.

Two 100 m3 fat storage tanks.

A reagent storage pit.

A dehydration platform equipped with an air washer.

A grinder n "ll.

 - A reception silo.

Claims (5)

 1) Process for treating household waste, sewage sludge and grease in order to recycle it, comprising the following steps. - loading into a brewing pit of a composition comprising: 60% of household waste 20% of sludge and grease, 20% of quicklime.  - Homogenization by means of the endless screw of the pit so as to raise the temperature from 250 to 300 "c and to produce a valued and dehydrated product. - Powder grinding of the valued product ready for use. 2) Treatment method according to claim N "I which consists, before loading, of shredding household waste and removing it to obtain a particle size of 8 to 10 cm. 3) Treatment process according to claim N I, which consists in incorporating sewage sludge and grease. 4) Treatment process according to claim N "I, which consists in incorporating quicklime in powder or small granules.  5) Industrial processing unit for implementing the method according to any one of the preceding claims, characterized in that it comprises the following materials. An industrial building, a refuse reception pit, a tn table, a NOI grinding unit equipped with steelwork (ferrous and non-ferrous), a mixing pit, two sludge and grease storage tanks, a storage storage pit reagent, a dehydration platform, a vacuum cleaner on an air washer, an N II grinding unit equipped with a dust collector, a silo, for receiving storage of finished products.