Patent assignee · US · COMPANY

CH2M HILL, INC.

45Patents
16Active
45Granted
44Portfolio score

Filing activity: Dec 28, 1993 → Oct 4, 2017 · 12 expiring within 5 years

Most-cited patents

PatentTitleAreaCited byStatus
US6863818B2 Method and apparatus for treating wastewater using membrane filters Emerging Cross-Sectional Technologies 84 Expired
US6517723B1 Method and apparatus for treating wastewater using membrane filters Emerging Cross-Sectional Technologies 80 Expired
US6946073B2 Method for treating wastewater in a membrane bioreactor to produce a low phosphorus effluent Emerging Cross-Sectional Technologies 79 Expired
US6295823A Apparatus and method for controlling temperature and humidity of a conditioned space Mechanical Engineering; Lighting; Heating 55 Expired
US5480548A Wastewater biological phosphorus removal process Emerging Cross-Sectional Technologies 45 Expired
US6905600B2 Method and apparatus for the treatment of particulate biodegradable organic waste Emerging Cross-Sectional Technologies 44 Expired
US7171787B2 Rectangular tilt-up concrete tank construction Fixed Constructions 19 Expired
US7103479B2 Method and system for evaluating water usage Human Necessities 19 Expired
US7062406B2 Method and system for water quality trading Physics 15 Expired
US7138048B1 Apparatus and method for the removal of solids and floatables from a wastewater stream Fixed Constructions 14 Expired
US7754090B1 Portable ultraviolet water treatment apparatus Emerging Cross-Sectional Technologies 12 Active
US6982036B2 Chemically enhanced primary sludge fermentation method Emerging Cross-Sectional Technologies 11 Expired
US5701953A Well head for environmental extraction wells Performing Operations; Transporting 10 Expired
US7311834B2 Apparatus for the treatment of particulate biodegradable organic waste Emerging Cross-Sectional Technologies 10 Active
US7029201B1 Utility line bedding for storm water management and storm water management system and method Fixed Constructions 10 Expired
US6534306B1 Modular biofilter unit and method of use Emerging Cross-Sectional Technologies 9 Expired
US7025884B2 Method and apparatus for treatment of a fluid system Chemistry; Metallurgy 7 Expired
US6728987B1 Method of adjusting the vertical profile of a cable supported bridge Fixed Constructions 7 Expired
US6723244B1 Method and apparatus to achieve nitrification at low solids retention times Emerging Cross-Sectional Technologies 7 Expired
US6783681B2 Method and apparatus for treatment of drinking water Performing Operations; Transporting 7 Expired
US6787041B2 Carbon dioxide enhanced complex-adsorption process for metal or metalloid removal from water Chemistry; Metallurgy 7 Expired
US7000711B2 Horizontal bore cryogenic drilling method Fixed Constructions 7 Expired
US6383803B1 Portable compostion system with reconfigurable air flow Emerging Cross-Sectional Technologies 5 Expired
US6352575B1 Apparatus and method for centralized recovery of volatile organic compounds Emerging Cross-Sectional Technologies 5 Expired
US7968760B2 Treatment of particulate biodegradable organic waste by thermal hydrolysis using condensate recycle Chemistry; Metallurgy 5 Active

Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.