CASE STUDY # 151
1. Headline: Kruger Inc. recovers whitewater at their
newsprint mill and reduces wastewater discharge and energy
costs.
2. Background: See below.
3. Cleaner Production Principle: process modification
4. Description of Cleaner Production Application: A series
of modest modifications to a newsprint mill have achieved
recovery of significant amounts of lean and clear
wastewaters that had been discharging to the sewer. Lean
whitewater from the company's three paper machine presses
are collected by gravity flow in a reservoir beneath the
machines. It is then pumped through a Sweco filter, where
90% is used for dilution of stock and 10% is sent to the
clarifier. Clear whitewater is now used instead of heated
freshwater on the paper machine showers.
Material/Energy and Balance and Substitution
FEEDSTOCKS: Whitewater from newsprint mill
WASTES: Wastewater
MEDIUM: Water
5. Economics
COST:
CAPITAL COST: Not reported
OPERATION/MAINTENANCE: Not reported
MONTHS TO RECOVER: Not reported
DISPOSAL & FEEDSTOCK: $580,000/yr
6. Advantages
FEEDSTOCK REDUCTION: 1.8 tons/day fiber recovered, which
represents $80,000/yr. Recovered lean whitewater led to
$500,000/yr savings.
WASTE PRODUCTION: Discharges to sewer significantly
reduced.
IMPACT/PROBLEMS: Efforts to recycle wastewaters,
previously discharged to the sewer, have greatly reduced
the volume of waste generated, and allow for recycling of
fiber feed material.
7. Constraints: No information provided.
8. Contacts and Citations: "Catalogue of Successful Hazardous
Waste Reduction/Recycling Projects", Energy Pathways Inc.
and Pollution Probe Foundation, prepared for Industrial
Programs Branch, Conservation & Protection Environment
Canada, March, 1987, page 64.
9. Keywords: United States, USA, pulp and paper, process
modification, whitewater, fiberfeed material, water
saving.
10. Reviewer's Comments: This case study was originally
abstracted for the US EPA's Pollution Prevention
Information Clearinghouse from the Canadian publication
"Catalogue of Successful Hazardous Waste
Reduction/Recycling Projects." It underwent a UNEP IE
funded technical review in 1994 for quality and
completeness. It was edited for the ICPIC diskette in
July 1995.
( Docno unep05: 450-003-A-362 )