20 Causes of problems in the Sewage Treatment Process

The following lists some items, chemicals, or uses which may have inhibiting effects on a sewage treatment process, particularly where the treatment system is a small one.

Please note: this list is not exhaustive, but it may assist in eliminating or confirming the reasons for failure of a Sewage Treatment System to perform correctly.

1) Photography
The chemicals used are varied but do contain silver nitrates which can be problematical.

2) Garden Weed Killers
These contain sodium nitrate, paraquat and arsenic in varying concentrations.

3) Drain Cleaners
A lot of these have a sulphuric acid base that can stop treatment.

4) Paints & Wood Preservatives
Some paints are lead based and preservatives contain phenols that severely affect treatment.

5) Floor or Brick Cleaners
Almost all these have a hydrochloric acid base that can stop treatment.

6) Antifreeze
This contains ethyl glycol that will affect treatment.

7) Engine Oil & Hydraulic Brake Fluid
The oils, both vegetable and mineral, provide a masking to biological growth.

8) Bleach
This contains caustic soda that can stop treatment.

9) Laundries
These produce high quantities of detergents and surfactants, which have severe inhibiting effects on treatment.

10) Dish & Glass Washers
These contain surfactants, caustic sodas, dyes and alcohols that have severe inhibiting effects on treatment.

11) All Purpose Cleaners
These contain sulphonates and amides that can have severe inhibiting effects on treatment.

12) Heavy Duty Cleaners
These contain sodium hydroxide and potassium hydroxide that can have severe inhibiting effects on treatment.

13) Food Processing
These contain effluents with a very high starch content which have severe inhibiting effects on treatment.

14) Textiles
These contain sodium hydroxide, acids and dyes that have severe inhibiting effects on treatment.

15) Laboratories
These will discharge chemicals of all types that have severe inhibiting effects on treatment.

16) Insecticides & Fungicides
These can contain mercury that will have severe inhibiting effects on treatment.

17) Paper & Paper-mills
These wastes contain bleaches, starches and dyes that have severe inhibiting effects on treatment.

18) Dairy Wastes
These are high strength wastes that produce oxygen reduction in wastes and will also contain chemicals from cleaning.

19) Greases
As OIL problems, these will cause blockages and have a masking effect on biological growth.

20) Petro-chemicals & Resins
These contain carbons and chemicals of all different types and treatment may be difficult.