On-Site Wastewater Treatment and Disposal Systems - Forced ...

on long-term performance of these nitrate removal systems for waste-
water. Numerous anions in water compete with nitrate for sites on these
resins; therefore, tests on the specific wastewater to be treated need
to be performed.
This process has potential for onsite application, where it would follow
a nitrification process such as intermittent sand filters. As with
ammonia resins, regeneration is performed off site.
There is insufficient information on nitrate exchange to provide design,
construction, operation, and maintenance data at this time.
6.6.3 Phosphorus Removal
6.6.3.1 Description
Table 6-27 outlines the most likely treatment processes available for
onsite removal of phosphorus in wastewater. In many instances, these
processes will also achieve other treatment objectives as well, and must
be evaluated as to their overall performance.
6.6.3.2 In-House Processes
Review of Chapter 4 indicates that the major sources of phosphorus in
the home are laundry, dishwashing, and toilet wastewaters. Contribu-
tions of phosphorus in the home could be reduced from approximately 4 to
2 gm/cap/day through the use of 0.5% phosphate detergents.
Segregation of toilet wastewaters (blackwater) from household waste-
waters reduces phosphorus levels to approximately 2.8 gm/cap/day in the
graywater stream. Chapter 4 describes the process features, perfor-
mance, and operation and maintenance of low-water carriage and waterless
toilet systems that would be employed for this segregation. Note that
the resultant residues from these toilet systems must be considered in
this treatment strategy. A discussion of residuals disposal appears in
Chapter 9.
As with any in-house measure to reduce pollutional loads, the success of
the process is dependent upon owner commitment and appropriate manage-
ment of the alternative plumbing equipment.
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